RUMINANT FEED COMPOSITION COMPRISING A MURAMIDASE

Abstract

The present invention relates to methods for improving digestibility in ruminants using ruminant feed comprising polypeptides having muramidase activity.

Description

FEED COMPOSITION FOR RUMINANTS THAT INCLUDES A MURAMIDASE i nnann / nznz / E / YiAi FIELD OF THE INVENTION The present invention relates to methods for improving digestibility in ruminants using ruminant feed comprising polypeptides having muramidase activity. BACKGROUND OF THE INVENTION Muramidase is a lysozyme also known as N-acetylmuramide glycanhydrolase, which is an O-glucosyl hydrolase produced by many organisms as a defense mechanism against bacteria. The enzyme causes hydrolysis of the bacterial cell wall by cleaving the glycosidic bonds of the peptidoglycans; an important structural molecule in bacteria. After the cell wall has been weakened by the action of muramidase, the bacterial cells lyse as a result of unbalanced osmotic pressure. Muramidase occurs naturally in many organisms, such as viruses, plants, insects, birds, reptiles, and mammals. In mammals, muramidase has been isolated from nasal secretions, saliva, tears, intestinal contents, urine, and milk. The enzyme cleaves the glycosidic bond between carbon number 1 of N-acetylmuramic acid and carbon number 4 of N-acetyl-DRef. 310697 glucosamine. In vivo, these two carbohydrates polymerize to form the cell wall polysaccharide of many microorganisms. Muramidases have been classified into seven different families of glycoside hydrolases (GH) (CAZy, www.cazy.org): GH18, GH19, the hen egg white lysozyme (GH22), the goose egg white lysozyme ( GH23), bacteriophage T4 muramidase (GH24), Sphingomoñas flagellar protein (GH73) and Chalaropsis muramidases (GH25). Muramidases of the GH23 and GH24 families are known mainly from bacteriophages and have only recently been identified in fungi. The GH25 muramidase family has been found to be structurally unrelated to the other muramidase families. In addition, an additional class of polypeptides having muramidase activity has been identified in PCT / CN2017 / 084074, muramidases are referred to herein as novel MUR polypeptides having muramidase activity, where muramidase activity is defined in the section on definition and representative muramidases are listed in the sequence listing. Muramidase has traditionally been extracted from chicken egg white and has been called chicken egg white lysozyme due to its natural abundance. Until recently, egg white lysozyme from i nnann / nznz / E / YiAi chicken was the only muramidase investigated for use in animal feed. Muramidase extracted from chicken egg white is the main product available on the commercial market, but it does not cleave N,6-Odiacetylmuramic acid in, for example, Staphylococcus aureus cell walls and is therefore not capable of lysing this important human pathogen among others (Masschalck B, Deckers D, Michiels CW (2002), Lytic and nonlytic mechanism of inactivation of gram-positive bacteria by muramidase under atmospheric and high hydrostatic pressure, J Food Prot. 65(12): 1916-23). WO2000 / 21381 describes a composition comprising at least two antimicrobial enzymes and a polyunsaturated fatty acid, wherein one of the antimicrobial enzymes was a GH22 muramidase from chicken egg white. GB2379166 describes a composition comprising a compound that disrupts the peptidoglycan layer of bacteria and a compound that disrupts the phospholipid layer of bacteria, wherein the compound that disrupts peptidoglycan was a muramidase GH22 from egg white of hen. WO2004 / 026334 describes an antimicrobial composition for suppressing the growth of enteric pathogens in the intestine of cattle comprising (a) a cell wall lysing substance or its salt, (b) an i nnann / nznz / E / YiAi substance antimicrobial, (c) a sequestering agent and (d) an antibiotic, wherein the cell wall lysing substance or its salt is muramidase GH22 from hen egg white. The demand for ruminant products, such as dairy products and meat, is on the rise, resulting in an increased demand for ruminant feed. An object of the invention is to improve nutrient use efficiency in feed to reduce the environmental impact of dairy and meat production. SUMMARY OF THE INVENTION The invention provides ruminant feed compositions, such as a ruminant feed, ruminant feed supplements or ruminant feed additives, comprising one or more muramidases, wherein the muramidase is in an amount sufficient for administration to a level of 1 to 200 mg of enzyme protein per kg of feed for ruminants. Furthermore, there is provided a method for increasing the dry matter digestibility of a ruminant feed, ruminant feed supplement or ruminant feed additive comprising the steps of: a) providing at least one muramidase; b) provide a ruminant feed, ruminant feed supplement or ruminant feed additive suitable for a ruminant i nnann / nznz / E / YiAi animal; c) applying the muramidase to the ruminant feed, ruminant feed supplement or ruminant feed additive to form a ruminant feed composition; and d) administering the ruminant feed composition to the ruminant animal, whereby an increase in dry matter digestibility is effected. In one embodiment of the invention, rumen volatile fatty acid (VEA) production is increased compared to rumen VEA production of a ruminant not fed a muramidase. In a further embodiment, rumen propionate production is increased compared to rumen propionate production of a ruminant not fed a muramidase and / or rumen propionate production is increased compared to of acetate in the rumen of a ruminant that is not fed muramidase. The muramidase used in the present invention may be of microbial origin. In one embodiment, the muramidase comprises one or more domains from a family of glycoside hydrolase (GH) selected from the list consisting of GH24, GH25, and novel MUR polypeptides having muramidase activity. BRIEF DESCRIPTION OF THE FIGURES Figure 1 shows the effect of 9 muramidases (A: SEQ. ID NO: 3, B: SEQ. ID NO: 6, C: SEQ. ID NO: 9, D: SEQ. ID NO: i nnann / nznz / E / YiAi 12, E: SEC. ID NO: 15, F: SEO. ID NO: 18, G: SEO. ID NO: 21, H: SEQ. ID NO: 24 and I: SEQ. ID NO: 27) of 3 different glycoside hydrolase (GH) families (GH24, GH25 and novel MUR polypeptides having muramidase activity) and positive control (PC, with monensin) on the relative improvement of dry matter digestibility, provided in percentage of improvement compared to the control after 48 h of fermentation in rumen liquid and buffer solution. Figure 2 shows the relative difference in rumen dry matter digestibility compared to the negative control as an effect of increasing the muramidase dose after 12 h of fermentation (NC is negative control, PC is positive control with monensin, A is SEQ ID NO: 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 18, E is SEQ ID NO: 9) . Figure 3 shows the relative difference in rumen acetate production compared to the negative control as an effect of increasing the muramidase dose after 12 h of fermentation (NC is negative control, PC is monensin positive control, A is SEQ ID NO: 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 18, E is SEQ ID NO: 9). Figure 4 shows the relative difference in ruminal propionate production compared to the negative control as an effect of increasing the dose of i nnann / nznz / E / YiAi muramidase after 12 h of fermentation (PC is positive control with monensin , A is SEQ ID NO: 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 18, E is SEQ ID NO: 9 ). Figure 5 shows the relative difference in rumen butyrate production compared to the negative control as an effect of increasing muramidase dose after 12 h of fermentation (PC is monensin positive control, A is SEQ ID NO : 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 18, E is SEQ ID NO: 9). Figure 6 shows the relative difference in total rumen VFA production compared to the negative control as an effect of increasing muramidase dose after 12 h fermentation (PC is monensin positive control, A is SEQ ID. NO: 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 18, E is SEQ ID NO: 9). Figure 7 shows the relative carbon difference in total rumen VFA production compared to the negative control as an effect of increasing muramidase dose after 12 h of fermentation (PC is monensin positive control, A is SEC ID NO: 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 18, E i nnann / nznz / E / YiAi is SEQ ID NOT: 9). Figure 8: shows the relative difference in ruminal dry matter digestibility compared to the negative control after 12 h of fermentation, as an effect of muramidase and monensin supplementation (NC is negative control, PC is positive control with monensin, A is SEQ ID NO: 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 29, E is SEQ ID NO: 30, F is SEQ ID NO: 31, G is SEQ ID NO: 32, H is SEQ ID NO: 33, I is SEQ ID NO: 34, J is SEQ ID NO: 35, K is SEQ ID NO: 36, L is SEQ ID NO: 36, M is SEQ ID NO: 37). Figure 9: shows the relative difference in rumen propionate concentration compared to the negative control after 12 h of fermentation, as an effect of muramidase and monensin supplementation (NC is negative control, PC is monensin positive control, A is SEQ ID NO: 28, B is SEQ ID NO: 21, C is SEQ ID NO: 12, D is SEQ ID NO: 29, E is SEQ ID NO: 30, F is SEQ ID NO: 31, G is SEQ ID NO: 32, H is SEQ ID NO: 33, I is SEQ ID NO: 34, J is SEQ ID NO: 35, K is SEQ ID NO: 36, L is SEQ ID NO: 36, M is SEQ ID NO: 37). Figure 10: shows the relative difference in rumen butyrate concentration compared to the negative control after 12 h of fermentation, as an effect of muramidase and monensin supplementation (NC is negative control, PC is monensin positive control, A is SEQ ID NO: 28, B is SEQ ID NO: 21, 0 is SEQ ID NO: 12, D is SEQ ID NO: 29, E is SEQ ID NO: 30, F is SEQ ID NO: 31, G is SEQ ID NO: 32, H is SEQ ID NO: 33, I is SEQ ID NO: 34, J is SEQ ID NO: 35, K is SEQ ID NO: 36, L is SEQ ID NO: 36, M is SEQ ID NO: 37). Figure 11: Shows the relative difference in total rumen VFA production compared to the negative control as an effect of muramidase supplementation after 12 h of fermentation (NC is negative control, PC is monensin positive control, A is the SEQ ID NO: 38, B is SEQ ID NO: 39, C is SEQ ID NO: 40, D is SEQ ID NO: 41, E is SEQ ID NO: 42, F is SEQ SEQ ID NO: 43, G is SEQ ID NO: 44, H is SEQ ID NO: 45, I is SEQ ID NO: 46, J is SEQ ID NO: 47, K is SEQ ID NO: 48, L is SEQ ID NO: 49, M is SEQ ID NO: 50, N is SEQ ID NO: 51, O is SEQ ID NO: 52, S is SEQ SEQ ID NO: 55, T is SEQ ID NO: 56, U is SEQ ID NO: 57, V is SEQ ID NO: 58, W is SEQ ID NO: 59, Y is SEQ ID NO: 53, Z is SEQ ID NO: 54). Figure 12: shows the relative carbon difference in rumen VFA production compared to the negative control as an effect of muramidase supplementation after 12 h of fermentation (NC is negative control, PC is monensin positive control, A is SEQ ID NO: 38, B is SEQ ID NO: 39, C is SEQ ID NO: 40, D is SEQ ID NO: 41, E is SEQ ID NO: 42, F is SEQ ID NO: 43, G is SEQ ID NO: 44, H is SEQ ID NO: 45, I is SEQ ID NO: 46, J is SEQ ID NO: 47, K is SEQ ID NO: 48, L is SEQ ID NO: 49, M is SEQ ID NO: 50, N is SEQ ID NO: 51, O is SEQ ID NO: 52, S is SEQ ID NO: 55, T is SEQ ID NO: 56, U is SEQ ID NO: 57, V is SEQ ID NO: 58, W is SEQ ID NO: 59, Y is SEQ ID NO: 53, Z is SEQ ID NO: 54). Figure 13: shows the relative difference in ruminal acetate production compared to the negative control as an effect of muramidase supplementation after 12 h of fermentation (NC is negative control, PC is monensin positive control, A is SEC ID NO: 38, B is SEQ ID NO: 39, C is SEQ ID NO: 40, D is SEQ ID NO: 41, E is SEQ ID NO: 42, F is SEQ ID NO: 43, G is SEQ ID NO: 44, H is SEQ ID NO: 45, I is SEQ ID NO: 46, J is SEQ ID NO: 47, K is SEQ ID NO: 48, L is SEQ ID NO: 49, M is SEQ ID NO: 50, N is SEQ ID NO: 51, O is SEQ ID NO: 52, S is SEQ ID NO: 55, T is SEQ ID NO: 56, U is SEQ ID NO: 57, V is SEQ ID NO: 58, W is SEQ ID NO: 59, Y is SEQ ID NO: 53, Z is SEQ ID NO: 54). Figure 14: shows the relative difference in rumen propionate production compared to the negative control as an effect of muramidase supplementation after 12 h of fermentation (NC is negative control, PC is monensin positive control, A is SEC . ID NO: 38, B is SEQ. ID NO: 39, C is SEQ. ID NO: 40, D is SEQ. ID NO: 41, E is SEC. ID NO: 42, F is SEC. ID NO: 43, G is SEC. ID NO: 44, H is SEQ. ID NO: 45, I is the SEC. ID NO: 46, J is SEQ. ID NO: 47, K is the SEQ.ID NO: 48, L is SEC. ID NO: 49, M is SEQ. ID NO: 50, Not the SEC. ID NO: 51, OR is the SEC. ID NO: 52, S is the SEQ.ID NO: 55, T is SEC. ID NO: 56, U is SEQ. ID NO: 57, V is SEQ. ID NO: 58, W is SEQ. ID NO: 59, Y is the SEQ.ID NO: 53, Z is SEC. ID NO: 54). BRIEF DESCRIPTION OF SEQUENCE LISTING The SEC. ID NO: 1 is the cDNA sequence of a muramidase polypeptide isolated from Trichoderma koningiopsis. The SEC. ID NO: 2 is the amino acid sequence deduced from SEQ. ID NO: 1. The SEC. ID NO: 3 is the amino acid sequence of the mature muramidase polypeptide from Trichoderma koningiopsis. The SEC. ID NO: 4 is the cDNA sequence of a muramidase polypeptide isolated from Thielavia terrestris. i nnann / nznz / E / YiAi The SEC. ID NO: 5 is the amino acid sequence deduced from SEQ. ID NO: 4 . The SEC. ID NO: 6 is the amino acid sequence of the mature terrestrial Thielavia muramidase polypeptide. The SEC. ID NO: 7 is the cDNA sequence of a muramidase polypeptide isolated from Tilletia indica. The SEC. ID NO: 8 is the amino acid sequence deduced from SEQ. ID NO: 7 . The SEC. ID NO: 9 is the amino acid sequence of the mature Tilletia indica muramidase polypeptide. The SEC. ID NO: 10 is the cDNA sequence of a muramidase polypeptide isolated from Acremonium alcalophilum. The SEC. ID NO: 11 is the amino acid sequence deduced from SEQ. ID NO: 10. The SEC. ID NO: 12 is the amino acid sequence of the mature muramidase polypeptide from Acremonium alcalophilum. The SEC. ID NO: 13 is the cDNA sequence of a muramidase polypeptide isolated from Cladorrhinum bulbillosum The SEC. ID NO: 14 is the amino acid sequence deduced from SEQ. ID NO: 13. The SEC. ID NO: 15 is the amino acid sequence of the mature muramidase polypeptide from Cladorrhinum bulbillosum. The SEC. ID NO: 16 is the cDNA sequence of a muramidase polypeptide isolated from Onygena equina. The SEC. ID NO: 17 is the amino acid sequence i nnann / nznz / E / YiAi deduced from SEQ. ID NO: 16. The SEC. ID NO: 18 is the amino acid sequence of the mature equine Onygena muramidase polypeptide. The SEC. ID NO: 19 is the cDNA sequence of a muramidase polypeptide isolated from Trichophaea saccata. The SEC. ID NO: 20 is the amino acid sequence deduced from SEQ. ID NO: 19. The SEC. ID NO: 21 is the amino acid sequence of the mature muramidase polypeptide from Trichophaea saccata. The SEC. ID NO: 22 is the cDNA sequence of a muramidase polypeptide isolated from Pleurotus ostreatus. The SEC. ID NO: 23 is the amino acid sequence deduced from SEQ. ID NO: 22. The SEC. ID NO: 24 is the amino acid sequence of the mature muramidase polypeptide from Pleurotus ostreatus. The SEC. ID NO: 25 is the cDNA sequence of a muramidase polypeptide isolated from Cladosporium sp-9768. The SEC. ID NO: 26 is the amino acid sequence deduced from SEQ. ID NO: 25. The SEC. ID NO: 27 is the amino acid sequence of the mature Cladosporium sp-97 68 muramidase polypeptide. The SEC. ID NO: 28 is the amino acid sequence of the mature muramidase polypeptide from Chaetomium thermophilum var. thermophilum. The SEC. ID NO: 29 is the amino acid sequence of the mature muramidase polypeptide from Acremonium alcalophilum. i nnann / nznz / E / YiAi The SEC. ID NO: 30 is the amino acid sequence of the mature muramidase polypeptide from Coprinopsis cinerea okayama. The SEC. ID NO: 31 is the amino acid sequence of the mature muramidase polypeptide from Rasamsonia brevistipitata. The SEC. ID NO: 32 is the amino acid sequence of the mature muramidase polypeptide from Acremonium alcalophilum. The SEC. ID NO: 33 is the amino acid sequence of the mature muramidase polypeptide from Poronia punctata. The SEC. ID NO: 34 is the amino acid sequence of the mature Aspergillus deflectus muramidase polypeptide. The SEC. ID NO: 35 is the amino acid sequence of the mature muramidase polypeptide from Poronia punctata. The SEC. ID NO: 36 is the amino acid sequence of the mature muramidase polypeptide from Paecilomyces sp. The SEC. ID NO: 37 is the amino acid sequence of the mature muramidase polypeptide from Hamigera sp. The SEC. ID NO: 38 is the amino acid sequence of the mature muramidase polypeptide from Penicillium citrinum. The SEC. ID NO: 39 is the amino acid sequence of the mature muramidase polypeptide from Pyronema domesticum. The SEC. ID NO: 40 is the amino acid sequence of the mature muramidase polypeptide from Thielavia sp. i nnann / nznz / E / YiAi The SEC. ID NO: 41 is the amino acid sequence of the mature muramidase polypeptide from Chaetomium sp. The SEC. ID NO: 42 is the amino acid sequence of the mature muramidase polypeptide from Metarhizium iadini. The SEC. ID NO: 43 is the amino acid sequence of the mature Aspergillus deflectus muramidase polypeptide. The SEC. ID NO: 44 is the amino acid sequence of the mature muramidase polypeptide from Sporormy fimetaria. The SEC. ID NO: 45 is the amino acid sequence of the mature muramidase polypeptide from Lecanicillium psalliotae. The SEC. ID NO: 46 is the amino acid sequence of the mature muramidase polypeptide from Trichocladium asperum. The SEC. ID NO: 47 is the amino acid sequence of the mature muramidase polypeptide from Clavicipitaceae sp-70249. The SEC. ID NO: 48 is the amino acid sequence of the mature muramidase polypeptide from Thielavia terrestris. The SEC. ID NO: 49 is the amino acid sequence of the mature Westerdykella muramidase polypeptide. The SEC. ID NO: 50 is the amino acid sequence of the mature equine Onygena muramidase polypeptide. The SEC. ID NO: 51 is the amino acid sequence of the mature muramidase polypeptide from Ovatospora brasiliensis. The SEC. ID NO: 52 is the amino acid sequence of the mature muramidase polypeptide from Purpureocillium lilacinum. The SEC. ID NO: 53 is the amino acid sequence of the mature i nnann / nznz / E / YiAi muramidase polypeptide from Ovatospora brasiliensis. The SEC. ID NO: 54 is the amino acid sequence of the mature muramidase polypeptide from Penicillium wellingtonense. The SEC. ID NO: 55 is the amino acid sequence of the mature muramidase polypeptide from Aspergillus sp. The SEC. ID NO: 56 is the amino acid sequence of the mature muramidase polypeptide from Chaetomium sp. The SEC. ID NO: 57 is the amino acid sequence of the mature muramidase polypeptide from Zopfiella sp. The SEC. ID NO: 58 is the amino acid sequence of the mature muramidase polypeptide from Acremonium exiguum. The SEC. ID NO: 59 is the amino acid sequence of the mature muramidase polypeptide from Chaetomium sp. DETAILED DESCRIPTION OF THE INVENTION DEFINITIONS Acetate: Acetate is used interchangeably herein with the term acetic acid and is one of the volatile fatty acids (VFAs) produced in the rumen. It is a precursor for the synthesis of mammalian milk fat and is also used for energy metabolism of muscle and synthesis of body fat. The amount of acetate in the rumen is a measure of the rumen fermentation of the ingested feed, thus an increase in rumen acetate i nnann / nznz / E / YiAi is an indication of increased energy supply for ruminants. Antimicrobial Activity: The term antimicrobial activity is defined herein as an activity that kills or inhibits the growth of microorganisms, such as algae, archaebacteria, bacteria, fungi, and / or protozoa. The antimicrobial activity can be, for example, bactericidal, meaning the killing of bacteria; or it may be bacteriostatic, meaning prevention of bacterial growth. Antimicrobial activity may include catalyzing the hydrolysis of 1,4-beta bonds between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan and between W-acetyl-D-glucosamine residues in chitodextrins. Antimicrobial activity may also include binding of muramidase to the surface of the microorganism and inhibiting its growth. The antimicrobial effect may also include the use of the muramidases of the present invention for activation of bacterial autolysins, as an immunostimulator, inhibiting or reducing bacterial toxins, and for an opsonin effect. Meat Production: The term meat production is defined herein as the production of meat from cattle raised for meat production. Meat production can be measured, for example, i nnann / nznz / E / YiAi by feed intake, daily feed intake, body weight gain, mean daily gain, present carcass dressing, composition of the carcass and carcass classification. Butyrate: Butyrate is used interchangeably herein with the term butyric acid and is one of the volatile fatty acids (VFA) produced in the rumen. It is a precursor to β-ΟΗ-butyrate for the synthesis of mammalian milk fat and is also used for energy metabolism of muscle and synthesis of body fat. The amount of butyrate in the rumen is a measure of the rumen fermentation of the ingested feed, so an increase in butyrate is an indication of increased energy supply for ruminants. Concentrates: The term concentrates means feed with a high and fast digestibility of dry matter (DMd). Concentrates are typically feeds with relatively high protein and / or energy concentrations and low Neutral Detergent Fiber (NDF) concentrations, such as molasses, oligosaccharides, sorghum, seeds, and grains (either whole or prepared by milling, crushing, etc. from eg corn, oats, rye, barley, wheat), oilseed presscake (eg cottonseed, safflower, sunflower, soybean, rapeseed / canola, peanut or peanut kernel), palm kernel cake, yeast-derived material, and distiller's grains (such as wet distiller's grains (WDS) and dry distiller's grains with solubles (DDGS)). Dry Matter Digestibility (DMd) : Digestibility refers to the extent to which a feed is broken down and absorbed in an animal's body as it passes through the digestive tract. The term "dry matter digestibility" means the disappearance of dry matter from the feed from the gastrointestinal (GI) tract by a given animal at a specified level of feed intake. The DMd is measured as the percentage difference in the dry matter (DM) ratio between the ingested feed and the excreted faeces from the ingested feed. The rumen DMd is therefore the percentage difference in the proportion of dry matter between the ingested and digested feed that passes into the distal compartments of the rumen and describes the potential for ruminant microbes to degrade and digest the MD of the feed. Energy Corrected Milk (ECM): Energy corrected milk is a means of adjusting milk production for the amount of the major components in the milk that affect the energy concentration (lactose, fat, and protein) in the milk and determines the amount of milk produced adjusted to 3.5 percent fat and 3.2 percent protein. ECM is calculated herein as described by Sjaunja, L.O., Baevre, L., Junkkarinen, L., Pedersen, J., Setala, J. A Nordic proposal for an energy corrected milk (ECM) formula in: P. Gaillon, Y. Chabert (Eds.) Performance Recording of Animals: State of the Art, 1990: Proceedings of the 27th Biennial Session of the International Committee for Animal Recording. Wageningen Academic Publishers, Wageningen, The Netherlands; 1991:156-157. Feed Conversion Ratio (FCR): FCR is a measure of the efficiency of an animal (herein a ruminant) in converting feed mass into the desired output, eg body mass. The FCR is calculated as the feed intake divided by the animal's weight gain, all over a specified period. By lower feed conversion ratio or improved feed conversion ratio it is meant that less feed is needed to increase the weight of the animal and / or the milk production of the animal. A 2% improvement in FCR means that the FCR was reduced by 2%. Feed efficiency: The expression feed efficiency is the ratio of live weight gain to dry matter intake (DMI) or energy-corrected milk production per kg dry matter intake (kg ECM / kg DMI ). The higher the number, the better. Fodder: The term fodder as defined herein also includes fodder rich in indigestible material. Forage is NDF-rich plant material, such as hay and silage from forage plants, grass and other forage plants, algae and legumes, or any combination of these. Examples of fodder plants are alfalfa, horned lotus, Brassica (for example kale, rapeseed, rutabaga, turnip), clover (for example Trifolium hybridum, red clover, subterranean clover, white clover), grass (for example Cynodon dactylon, Bromus, Arrhenatherum elatius, Festuca, Danthonia decumbens, Poa, Dactylis, Lolium, Phleum pratense), whole crop products using corn, millet, barley, oats, rye, sorghum, soybean and wheat and vegetables such like beets. Fodder also includes crop residues from grain production (such as corn stover; wheat straw, barley, oats, rye, and other grains); vegetable residues such as beetroot tops; waste from oilseed production such as stems and leaves of soybeans, rapeseed and other legumes. Fungal Muramidase: The term "fungal muramidase" means a polypeptide having muramidase activity that is or can be obtained from a fungal source. Examples of fungal sources are fungi; that is, the muramidase is or can be obtained from the kingdom Fungi, where the term kingdom is the taxonomic category. In particular, fungal muramidase is or can be obtained from the phylum Ascomycota, such as the subphylum Pezizomycotina, where the terms phylum and subphylum are the taxonomic categories. If the taxonomic status of a polypeptide is unknown, it can be readily determined by one of ordinary skill in the art by performing a BLASTP search for the polypeptide (using, for example, the National Center for Biotechnology Information (NCIB) website http: / / www.ncbi.nlm.nih.gov / ) and comparing it to its closest counterparts. An unknown polypeptide that is a fragment of a known polypeptide is considered to be from the same taxonomic species. An unknown natural polypeptide or artificial variant comprising a substitution, deletion and / or insertion at up to 10 positions is considered to be from the same taxonomic species as the known polypeptide. Ionophore: The term ionophore is used herein for antibiotics, eg, macrolide antibiotics and / or growth-enhancing feed additives for animals such as ruminants, that catalyze the transport of ions across hydrophobic membranes, such as bilayers. lipids found in living cells and show high affinities for ions, such as, for example, Na+, H+, Ca2+, Mg2+ and / or K+. Examples of ionophores include, without limitation, monensin, which, for example, is used in the i nnann / nznz / E / YiAi meat and dairy industries to prevent coccidiosis, increase propionic acid production, and prevent tympanitis. Isolated: The term isolated refers to a substance in a form or environment that is not found in nature. Non-limiting examples of isolated substances include (1) any substance that does not occur naturally, (2) any substance, including, but not limited to, any enzyme, variant, nucleic acid, protein, peptide, or cofactor, that has been separated, at least in part, from one or more or all of the naturally occurring constituents with which it is associated in nature; (3) any substance modified by human intervention from the substance found in nature; or (4) any substance modified by increasing the amount of the substance relative to other components with which it is naturally associated (for example, multiple copies of a gene encoding the substance; the use of a more powerful promoter than the promoter naturally associated with the gene encoding the substance). An isolated substance may be present in a sample of fermentation broth. Mature Polypeptide: The term "mature polypeptide" refers to a polypeptide in its final form after translation and any post-translational modifications, such as N-terminal processing, C-terminal truncation, glycosylation, phosphorylation, etc. Milk production: The term milk production is used to describe the total milk production of dairy cattle. Milk production is measured in the total amount of milk produced, it can be expressed as daily milk production or milk production per lactation, defined as the period from the day of calving to dry off, defined as the day the cow leaves to give milk Drying day is normally about 300 days after calving. Milk production is measured in kg milk or energy corrected kg milk (ECM) to account for variation in milk solids. Muramidase: The term muramidase is used for polypeptides that have glycoside hydrolase activity and catalyze the hydrolysis of beta-1,4 bonds between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan. In turn, hydrolysis compromises the integrity of bacterial cell walls, causing lysis of the bacteria. Other terms for muramidase include lysozyme and N-acetylmuramide glucanhydrolase. Muramidase Activity: The term muramidase activity means the enzymatic hydrolysis of beta-1,4 bonds between W-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan or between N-acetyl-D-glucosamine residues in chitodextrins, causing bacteriolysis due to osmotic pressure. Muramidase belongs to the EC 3.2.1.17 class of enzymes. Muramidase activity is typically measured by turbidimetric determination. The method is based on changes in the turbidity of a suspension of Micrococcus luteus ATCC 4698 induced by the lytic action of muramidase. Under suitable experimental conditions, these changes are proportional to the amount of muramidase in the medium (see, INS 1105 of the Compendium of Specifications for Food Additives of the Food and Agriculture Organization of the United Nations (www.fao.org)). . Organic matter digestibility (DMd): The digestibility of organic matter is defined as the DMd, but where the amount of organic matter is calculated as: 0M=DM-ash, where the ash content is determined after total combustion of the DM of the feed. Propionate: Propionate is used herein interchangeably with the term propionic acid and is one of the volatile fatty acids (VFA) produced in the rumen. Propionate is the main precursor for glucose synthesis by ruminants, glucose is used for lactose metabolism and energy. The amount of propionate in the rumen is a measure of rumen fermentation of ingested feed, thus an increase in rumen i nnann / nznz / E / YiAi propionate is an indication of increased glucose supply for ruminants. Ruminant: The term ruminant means an animal that digests plant-based feed initially by fermenting / degrading it in the animal's first compartment of the stomach complex, primarily through bacterial action, subsequently retaining the small particles and regurgitating the semi-degraded mass, now known as ruminate and chew it again. The process of re-chewing the rumination to further break down the plant matter and stimulate digestion is called rumination. Examples of ruminants are cattle, cows, dairy cattle, food cattle, buffaloes, calves, goats, sheep, lambs, deer, reindeer, yaks, camels, and llamas. Feed for ruminants: The expression feed for ruminants or feed for ruminant animals refers to any compound, preparation or mixture suitable or intended for ingestion by a ruminant. Ruminant feed typically comprises forages (including fresh grass, forage rich in indigestible material, and silage) and may further comprise concentrates, as well as vitamins, minerals, enzymes, direct delivery microbial agents (DMF), amino acids, and / or other ingredients. of feed (such as in a premix). Ruminant feed can be fed in the form of a Total Mixed Ration (TMR), where all feed components are mixed together prior to feeding and fed as a mix or as a Partial Mixed Ration (PMR). ), where most of the feed components are mixed and fed together, but part of the concentrate is fed separately or may be fed as a feed for separate feeding, where all components are fed separately without mixing. Sequence identity: The degree of relatedness between two nucleic acid sequences or between two nucleotide sequences is described by the sequence identity parameter. For purposes of the present invention, sequence identity between two amino acid sequences is determined using the Needleman-Wunsch algorithm (Needleman and Wunsch, 1970, J. Mol. Biol. 48: 443-453) as implemented in the program Needle from the EMBOSS package (EMBOSS: The European Molecular Biology Open Software Suite, Rice et al., 2000, Trends Genet. 16: 276-277), preferably version 5.0.0 or later. The parameters used are gap opening penalty of 10, gap extension penalty of 0.5, and the substitution matrix EBLOSUM62 (EMBOSS version of BLOSUM62). The Needle result identified as the longest identity (obtained using the short no i nnann / nznz / E / YiAi option) is used as the percent identity and is calculated as follows: (Identical remains x 100) / (Alignment length Total number of gaps in the alignment).Silage: Silage is a type of forage that is produced from the natural fermentation of moist plant material, such as fresh grass and whole crops. such as corn and barley. The fermentation process is carried out to preserve the moist material, in such a way that it can be used throughout the year. Substantially pure polypeptide: The term "substantially pure polypeptide" refers to a preparation containing at most 10%, at most 8%, at most 6%, at most 5%, at most 4%, at most 3 %, at most 2%, at most 1% and at most 0.5% by weight of other polypeptide material with which it is naturally or recombinantly associated. Preferably, the polypeptide is at least 92% pure, for example, at least 94% pure, at least 95% pure, at least 96% pure, at least one 97%, a purity of at least 98%, at least 99%, a purity of at least 99.5% and a purity of 100% by weight of the total polypeptide material present in the preparation. The polypeptides of the present invention are preferably in substantially pure form. i nnann / nznz / E / YiAi This can be achieved, for example, by preparing the polypeptide by commonly used recombinant methods or by classical purification methods. Variant: The term variant means a polypeptide having muramidase activity that comprises an alteration, ie, a substitution, insertion and / or deletion of one or more (several) amino acid residues at one or more (eg, several) positions. A substitution means the replacement of the amino acid occupying a position with a different amino acid; a deletion means the removal of the amino acid occupying a position; and an insertion means adding 1, 2 or 3 amino acids adjacent to and just after the amino acid occupying the position. In one aspect, a muramidase variant according to the invention may comprise 1 to 5; from 1 to 10; from 1 to 15; from 1 to 20; from 1 to 25; from 1 to 30; from 1 to 35; from 1 to 40; from 1 to 45; or 1-50, i.e. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 alterations and have at least 20%, for example, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least least 90%, at least 95% or at least 100% of the muramidase activity of the parent muramidase, such as SEQ. ID NO: 3, SEQ. ID NO: 6, SEQ. ID NO: 9, SEQ. ID NO: 12, SEQ. ID i nnann / nznz / E / YiAi NOT: 15, SEO. ID NO: 18, SEO. ID NO: 21, SEO. ID NO: 24, SEO. ID NO: 27, SEO. ID NO: 28, SEO. ID NO: 29, SEO. ID NO:30, SEO. ID NO: 31, SEO. ID NO: 32, SEO. ID NO: 33, SEO. ID NO: 34, SEO. ID NO: 35, SEO. ID NO: 36, SEO. ID NO: 37, SEO. ID NOT: 38, SEO. ID NO: 39, SEO. ID NO: 40, SEO. ID NO: 41, SEO. ID NO: 42, SEO. ID NO: 43, SEO. ID NO: 44, SEO. ID NO:45, SEO. ID NO: 46, SEO. ID NO: 47, SEO. ID NO: 48, SEO. ID NO: 49, SEO. ID NO: 50, SEO. ID NO: 51, SEO. ID NO: 52, SEO. ID NOT: 53, SEO. ID NO: 54, SEO. ID NO: 55, SEO. ID NO: 56, SEO. ID NO: 57, SEO. ID NO: 58, and SEO. ID NO: 59. Volatile Fatty Acids (VFAs) / Short Chain Fatty Acids (SCFAs): Volatile Fatty Acids (VFAs), also called Short Chain Fatty Acids (SCFAs), are fatty acids with fewer than six carbon atoms and include, for example , acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid and isovaleric acid. Volatile fatty acids (VFA) are produced from the fermentation of carbohydrates in the rumen and provide the main source of energy in ruminants. Therefore, the increase in VFA can be used as an indication of the increase in energy and nutrient supply for ruminants. Methods to improve the performance of ruminants The use of nutrients from ruminant feed is important for optimal production and animal health in modern production systems. Surprisingly, it has been found that supplementation of a ruminant feed with a muramidase according to the invention results in increased digestibility of rumen dry matter compared to when the ruminant feed is supplemented without the muramidase (as a control). By increasing the digestibility of rumen dry matter, ruminants are provided with more nutrients for production. In this way, the efficiency of nutrient use has been improved and the conversion of organic matter has been increased, such as, for example, microbial protein in milk by dairy cattle or in meat by slaughter cattle, compared to the conversion obtained with feed for ruminants without muramidase. In addition, it has surprisingly been found that rumen dry matter digestibility is improved in comparison to rumen dry matter digestibility obtained when commonly used commercially used ionophores for ruminants are provided. In one aspect of the invention, the nutrient use efficiency of the ruminant feed is increased. By increasing the nutrient use of ruminant feed, the same amount of milk and / or meat can be produced from fewer ruminant animals, reducing the use of natural resources and greenhouse gas (GHG) emissions per unit of milk and / or unit of meat produced. It also leads to a reduction in nitrogen and phosphate excretion per ruminant animal and therefore a total reduction in phosphate and nitrogen excretion per unit of production. Determination of dry matter digestibility can be carried out, for example, using an in vitro fermentation model adapted from Menke KH, Steingass H. 1988 (Estimation of the energetic feed value obtained from Chemical analysis and in vitro gas production using rumen fluid. Anim Res Dev. (1988) 28:7-55) as described in Example 1. In one aspect, volatile fatty acid (VEA) production is increased in the rumen as compared to VEA produced in the rumen of a ruminant not fed a muramidase. In one aspect, propionate production in the rumen is increased as compared to propionate produced in the rumen of a ruminant not fed a muramidase. In one aspect, rumen acetate production is increased compared to rumen acetate production of a ruminant not fed a muramidase. In one embodiment, the muramidase is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed, such as 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 to 75 mg, 5 to 50 mg, 5 to 40 mg, 10 to 50 or 5 to 25 mg of enzyme protein per kg DM of ruminant feed or any combination of these ranges. In one embodiment, the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, cattle, buffalo, young calf, goat, sheep, lamb, deer, yak, camel, and llama. In a further modality, the ruminant is selected from the group consisting of cattle, dairy cattle, and livestock. The muramidase can be provided to the ruminant for any period of time from birth to slaughter. In a preferred embodiment, the muramidase is provided to the ruminant on a daily basis. In a further embodiment, the muramidase is provided to the ruminant daily for the lifetime of the ruminant. In one embodiment, the muramidase is administered to ruminants selected from the group consisting of: cattle, cows, dairy cattle, cattle, buffalo, calf, goat, sheep, lamb, deer, yak, camel, and llama. In one embodiment, the muramidase is administered to growing ruminants. In one embodiment, the muramidase is administered to dairy cattle. In a further embodiment, the muramidase is administered to dairy cattle during lactation. In one embodiment, the muramidase is administered to beef cattle in the growth phase of i nnann / nznz / E / Y production of the beef cattle. In one embodiment, the muramidase is administered to livestock at the finish phase of livestock production. The muramidase can be administered to the animal in any suitable way. In one embodiment, the muramidase is fed to the ruminant in a feed, feed supplement or feed additive. In another embodiment, the muramidase is administered to the ruminant in the drinking water. In yet another embodiment, the muramidase is administered to the ruminant in the form of a bolus administration. In yet another embodiment, the muramidase is administered to the ruminant as a post-feed spray application applied to the ruminant's feed. In one embodiment, the muramidase is administered to the ruminant in liquid form as a beverage. In another embodiment, the muramidase is administered to the ruminant in liquid form as a drench. In another embodiment, the muramidase is administered to the ruminant in milk or a milk replacer. In one embodiment, the muramidase is of microbial origin. In a further embodiment, the muramidase is of fungal origin. In one embodiment, the muramidase is or can be obtained from the phylum Ascomycota, as well as the subphylum Pezizomycotina. In one embodiment, the muramidase comprises one or more domains from a family of glycoside hydrolase (GH) i nnann / nznz / E / YiAi selected from the list consisting of GH24, GH25 and novel MUR polypeptides having muramidase activity. In one embodiment, the muramidase comprises one or more domains of the GH24 family of glycoside hydrolase (GH). In one embodiment, the muramidase comprises one or more domains of the GH25 family of glycoside hydrolase (GH). In one embodiment, the muramidase comprises one or more domains of novel MUR polypeptides having muramidase activity. In a preferred embodiment, the invention relates to a method for improving dry matter digestibility (DMd) and / or volatile fatty acid (VEA) production and / or meat production and / or milk production of a ruminant comprising administering to the ruminant a ruminant feed, a ruminant feed supplement or a ruminant feed additive comprising one or more muramidases, wherein: (a) the muramidase is a muramidase comprising one or more domains from a family of glycoside hydrolase (GH) selected from the list consisting of GH24, GH25, and novel MUR polypeptides having muramidase activity and is administered at a level of 1 at 200 mg of enzyme protein per kg of DM of feed for ruminants; (b) the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, cattle 6 stock, buffalo, calf, goat, sheep, lamb, deer, yak, camel and llama; and (c) dry matter digestibility (DMd) and / or volatile fatty acid (VFA) production and / or meat production and / or milk production is improved by at least 1% compared to a control; and (d) optionally, the muramidase is administered to the ruminant daily for at least 30 days during the ruminant's lifetime. In one embodiment of the method, energy corrected milk production (ECM) is improved by at least 1.25%, such as by at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another mode, ECM production improves by 1% to 5%, such as 1% to 4%, 1% to 3%, 1.25% to 2.5%, or 1.5%. % and 2% compared to control or any combination of these ranges. In one embodiment of the method, rumen dry matter (DMd) digestibility is improved by at least 1%, such as by at least 1.5%, at least 1.75% or at least 2.0% compared to the control. In another modality, the digestibility of dry matter is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5% or a 2% and 5% compared to control or any combination of these ranges. i nnann / nznz / E / YiAi In one embodiment of the method, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and any combination thereof. In a further embodiment, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, and any combination thereof. In a still further embodiment, the volatile fatty acid (VEA) is acetate and / or propionate. In one embodiment of the method, volatile fatty acid (VEA) is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to the control. In another embodiment, the volatile fatty acid is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2%. and 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is acetate. In a further embodiment, the acetate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, the acetate is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and a 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is propionate. In a further embodiment, i nnann / nznz / E / YiAi propionate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, propionate improves by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, the FCR is improved by at least 1%, such as at least 1.25%, at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, the FCR improves by between 1% and 10%, such as between 1% and 9%, such as between 1% and 8%, such as between 1% and 7%, such as between 1% and 6%, such as between 1% and 5%, such as between 1% and 4%, between 1% and 3%, between 1.25% and 2.5% or between 1.5% and 2% compared to control or any combination of these ranges. A 1% improvement in FCR is defined as a 1 / 100 reduction in the FCR of the ruminant supplemented with muramidase compared to the FCR of the ruminant not supplemented with muramidase. In one embodiment, the muramidase is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed, such as 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 at 75 mg, 5 to 50 mg, 5 to 40 mg, 10 to 50 or 5 to 25 mg enzyme protein per kg feed for i nnann / nznz / E / YiAi ruminants or any combination of these ranges. In one embodiment, the muramidase is administered to the ruminant for any period of time, from birth to slaughter. In a preferred embodiment, the muramidase is provided to the ruminant on a daily basis. In a further embodiment, the muramidase is administered to the ruminant daily for the lifetime of the ruminant. In one embodiment, the muramidase is administered to growing ruminants. In one embodiment, the muramidase is administered to dairy cattle. In a further embodiment, the muramidase is administered to dairy cattle during lactation. In one embodiment, the muramidase is administered to dairy cattle in the growth phase of dairy cattle production. In one embodiment, the muramidase is administered to livestock at the finish phase of livestock production. In a further embodiment, the muramidase is administered to calves in the milk. In one embodiment, the muramidase is administered to ruminants selected from the group consisting of: cattle, cows, dairy cattle, cattle, buffalo, calf, goat, sheep, lamb, deer, yak, camel, and llama. In one embodiment, the muramidase is of microbial origin. In a further embodiment, the muramidase is of fungal origin. In one embodiment, muramidase is obtained or can be obtained i nnann / nznz / E / YiAi from the phylum Ascomycota, as well as from the subphylum Pezizomycotína. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 3. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 3 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 3 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 3. In another embodiment, the muramidase is a variant of the SEQ. ID NO: 3, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 3 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 3 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 3 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 3 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: is no greater than 10, e.g. e.g., i nnann / nznz / E / YiAi 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 6. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 6 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 6 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 6. In another embodiment, the muramidase is a variant of SEQ. ID NO: 6, wherein the variant has i nnann / nznz / E / Y muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2 , 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 6 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 6 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 6 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 6 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 6 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. i nnann / nznz / E / YiAi In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 9. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 9 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 9 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 9. In another embodiment, the muramidase is a variant of SEQ. ID NO: 9, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 9 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 9 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 9 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 9 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 9 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 12. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 12 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the i nnann / nznz / E / YiAi fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 12 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 12. In another embodiment, the muramidase is a variant of SEQ. ID NO: 12, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 12 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 12 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 12 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 12 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 12 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91% , at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or the 100% sequence identity to SEQ. ID NO: 15. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 15 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 15 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 15. In another embodiment, the muramidase is a variant of SEQ. ID NO: 15, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 15 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 15 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 15 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 15 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 15 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at i nnann / nznz / E / Y less than 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93 %, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 18. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 18 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 18 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 18. In another embodiment, the muramidase is a variant of SEQ. ID NO: 18, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, i nnann / nznz / E / YiAi 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 18 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 18 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 18 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 18 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 18 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at least 87%, at least 88%, at least 89%, at least i nnann / nznz / E / Y 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 21. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 21 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 21 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 21. In another embodiment, the muramidase is a variant of SEQ. ID NO: 21, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, i nnann / nznz / E / YiAi 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 21 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 21 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 21 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 21 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 21 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 24. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 24 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 24 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 24. In another embodiment, the muramidase is a variant of SEQ. ID NO: 24, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 24 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 24 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 24 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 24 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 24 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least one 97%, at least 98%, at least 99% or 100% sequence identity to SEQ. ID NO: 27. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 27 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 27 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 27. In another embodiment, the muramidase is a variant of SEQ. ID NO: 27, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the i nnann / nznz / E / YiAi number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in the SEQ. ID NO: 27 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 27 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 27 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 27 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 27 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 28. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 28 or an allelic variant thereof; or is a fragment thereof i nnann / nznz / E / YiAi that has muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 28 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 28. In another embodiment, the muramidase is a variant of SEQ. ID NO: 28, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 28 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 28 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 28 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 28 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 28 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% i nnann / nznz / E / YiAi sequence identity to SEQ. ID NO: 29. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 29 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the i nnann / nznz / E / YiAi fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 29 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 29. In another embodiment, the muramidase is a variant of SEQ. ID NO: 29, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 29 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 29 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 29 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 29 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 29 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 30. In one embodiment, the muramidase comprises or consists of i nnann / nznz / E / YiAi the amino acid sequence of SEQ. ID NO: 30 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 30 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 30. In another embodiment, the muramidase is a variant of SEQ. ID NO: 30, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 30 is between 1 and 45, such as i nnann / nznz / E / YiAi as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10 or 1 -5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 30 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 30 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 30 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 30 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 31. In one embodiment, the muramidase comprises or consists of i nnann / nznz / E / YiAi the amino acid sequence of SEQ. ID NO: 31 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 31 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 31. In another embodiment, the muramidase is a variant of SEQ. ID NO: 31, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 31 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 i nnann / nznz / E / YiAi positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 31 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 31 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 31 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 31 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 32. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 32 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 32 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 32. In another embodiment, the muramidase is a variant of SEQ. ID NO: 32, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 32 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 32 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 32 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 32 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 32 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 33. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 33 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 33 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 33. In another embodiment, the muramidase is a variant of SEQ. ID NO: 33, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 33 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions that i nnann / nznz / E / YiAi comprise one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in the SEQ. ID NO: 33 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 33 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 33 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 33 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 34. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 34 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 34 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 34. In another embodiment, the muramidase is a variant of SEQ. ID NO: 34, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 34 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 34 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 34 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 34 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 34 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 35. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 35 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 35 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 35. In another embodiment, the muramidase is a variant of SEQ. ID NO: 35, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 35 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. i nnann / nznz / E / YiAi ID NO: 35 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 35 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 35 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 35 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 36. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 36 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 i nnann / nznz / E / YiAi amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 36 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 36. In another embodiment, the muramidase is a variant of SEQ. ID NO: 36, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 36 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 36 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, i nnann / nznz / E / YiAi or 10. In another embodiment, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 36 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 36 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 36 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, by i nnann / nznz / E / YiAi less than 94%, at least 95%, at least 96%, at least one 97%, at least 98%, at least 99%, or 100% identity sequence with SEQ. ID NO: 37. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 37 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 37 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 37. In another embodiment, the muramidase is a variant of SEQ. ID NO: 37, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 37 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 37 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In another embodiment, the number of substitutions, i nnann / nznz / E / YiAi deletions, and / or insertions in the SEQ. ID NO: 37 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 37 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 37 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 38. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 38 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 38 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 38. In another embodiment, the muramidase is a variant of SEQ. ID NO: 38, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 38 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 38 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 38 is no greater than i nnann / nznz / E / YiAi than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 38 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 38 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 39. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 39 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or i nnann / nznz / E / YiAi consists of the amino acid sequence of SEQ. ID NO: 39 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 39. In another embodiment, the muramidase is a variant of SEQ. ID NO: 39, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 39 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 39 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 39 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In an i nnann / nznz / E / YiAi additional embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 39 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 39 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 40. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 40 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 40 or an allelic variant thereof and a His tag and / or an i nnann / nznz / E / YiAi N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 40. In another embodiment, the muramidase is a variant of SEQ. ID NO: 40, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 40 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 40 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 40 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, i nnann / nznz / E / YiAi preferably conservative substitutions, in SEQ. ID NO: 40 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 40 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 41. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 41 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 41 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 41. In another embodiment, the muramidase is a variant of SEQ. ID NO: 41, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 41 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 41 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 41 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID i nnann / nznz / E / YiAi NOT: 41 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 41 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 42. i nnann / nznz / E / YiAi In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 42 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. . ID NO: 42 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEC. ID NO: 42. In another embodiment, the muramidase is a variant of SEQ. ID NO: 42, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 42 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 42 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 42 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 42 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or i nnann / nznz / E / YiAi 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 42 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 43. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 43 or an allelic variant thereof; or is a fragment of the same i nnann / nznz / E / YiAi that has muramidase activity, where the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 43 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEC. ID NO: 43. In another embodiment, the muramidase is a variant of SEQ. ID NO: 43, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 43 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 43 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 43 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 43 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative i nnann / nznz / E / YiAi substitutions in the SEC. ID NO: 43 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 44. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 44 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 44 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 44. In another embodiment, muramidase is a variant of i nnann / nznz / E / YiAi SEQ. ID NO: 44, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 44 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 44 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 44 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 44 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 44 is no greater than 10, e.g. e.g., i nnann / nznz / E / YiAi 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 45. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 45 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 45 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 45. In another embodiment, the muramidase is a variant of SEQ. ID NO: 45, wherein the variant has i nnann / nznz / E / Y muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2 , 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 45 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 45 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 45 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 45 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 45 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. i nnann / nznz / E / YiAi In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 46. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 46 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 46 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 46. In another embodiment, the muramidase is a variant of SEQ. ID NO: 46, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 46 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 46 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 46 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 46 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 46 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 47. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 47 or an allelic variant thereof; or is a fragment thereof that has muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 47 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 47. In another embodiment, the muramidase is a variant of SEQ. ID NO: 47, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 47 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 47 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 47 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 47 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 47 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one i nnann / nznz / E / YiAi 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91% , at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or the 100% sequence identity to SEQ. ID NO: 48. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 48 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 48 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 48. In another embodiment, the muramidase is a variant of SEQ. ID NO: 48, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 48 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 48 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 48 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 48 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 48 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at i nnann / nznz / E / Y less than 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93 %, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 49. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 49 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 49 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 49. In another embodiment, the muramidase is a variant of SEQ. ID NO: 49, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, i nnann / nznz / E / YiAi 100 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 49 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 49 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 49 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 49 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 49 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86 %, at least 87%, at least 88%, at least 89%, at least i nnann / nznz / E / Y 101 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 50. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 50 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 50 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 50. In another embodiment, the muramidase is a variant of SEQ. ID NO: 50, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, i nnann / nznz / E / YiAi 102 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 50 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 50 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 50 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 50 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 50 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at 103 at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 51. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 51 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 51 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 51. In another embodiment, the muramidase is a variant of SEQ. ID NO: 51, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another mode, the 104 number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 51 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 51 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 51 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 51 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 51 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least one 105 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ. ID NO: 52. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 52 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 52 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 52. In another embodiment, the muramidase is a variant of SEQ. ID NO: 52, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions. In another embodiment, the number i nnann / nznz / E / YiAi of positions comprising one or more substitutions 106 amino acids and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 52 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 52 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 52 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 52 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 52 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% identity 107 of sequence with SEC. ID NO: 53. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 53 or an allelic variant thereof; or is a fragment thereof i nnann / nznz / E / YiAi that has muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 53 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 53. In another embodiment, the muramidase is a variant of SEQ. ID NO: 53, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or 108 one or more amino acid insertions or any combination thereof in SEQ. ID NO: 53 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 53 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 53 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 53 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 53 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% i nnann / nznz / E / YiAi sequence identity to SEQ. ID NO: 54. 109 In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 54 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the i nnann / nznz / E / YiAi fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 54 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 54. In another embodiment, the muramidase is a variant of SEQ. ID NO: 54, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination 110 of the same in the SEC. ID NO: 54 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 54 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 54 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 54 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 54 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 55. In one embodiment, the muramidase comprises or consists of i nnann / nznz / E / YiAi 111 the amino acid sequence of SEQ. ID NO: 55 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 55 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 55. In another embodiment, the muramidase is a variant of SEQ. ID NO: 55, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 55 is between 1 and 45, such as i nnann / nznz / E / YiAi 112 as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10 or 1-5 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 55 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 55 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 55 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 55 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 56. In one embodiment, the muramidase comprises or consists of i nnann / nznz / E / YiAi the amino acid sequence of SEQ. ID NO: 56 or one 113 allelic variant of the same; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 56 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 56. In another embodiment, the muramidase is a variant of SEQ. ID NO: 56, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 56 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 i nnann / nznz / E / YiAi 114 positions. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 56 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 56 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 56 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 56 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 57. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 57 or an allelic variant thereof; or is it a fragment of it 115 having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 i nnann / nznz / E / YiAi amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 57 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 57. In another embodiment, the muramidase is a variant of SEQ. ID NO: 57, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 57 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions that 116 comprise one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 57 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 57 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 57 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEC. ID NO: 57 is no greater than 10, e.g. ej. , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 58. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 58 or an allelic variant thereof; or is a fragment thereof that has muramidase activity, wherein the fragment 117 comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 58 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 58. In another embodiment, the muramidase is a variant of SEQ. ID NO: 58, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 58 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions that i nnann / nznz / E / YiAi comprise one or more amino acid substitutions and / or one or 118 plus amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 58 is no greater than 10, e.g. e j ., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEC. ID NO: 58 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 58 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the SEQ. ID NO: 58 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In one embodiment, the muramidase is at least 50%, eg, at least 60%, at least 70%, at least one 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least one 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% , at least 99% or 100% sequence identity to SEQ. ID NO: 59. In one embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 59 or an allelic variant thereof; or is a fragment thereof having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 119 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. In another embodiment, the muramidase comprises or consists of the amino acid sequence of SEQ. ID NO: 59 or an allelic variant thereof and a His tag and / or an N-terminal and / or C-terminal HQ tag. In another aspect, the polypeptide comprises or consists of amino acids 1 to 213 of SEQ. ID NO: 59. In another embodiment, the muramidase is a variant of SEQ. ID NO: 59, wherein the variant has muramidase activity and comprises one or more substitutions and / or one or more deletions and / or one or more insertions or any combination thereof in 1, 2, 3, 4, 5, 6 , 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 positions. In another embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in SEQ. ID NO: 59 is between 1 and 45, such as 1-40, 1-35, 1-30, 1-25, 1-20, 1-15, 1-10, or 1-5 places. In one embodiment, the number of positions comprising one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more insertions of i nnann / nznz / E / YiAi 120 amino acids or any combination thereof in SEQ. ID NO: 59 is no greater than 10, e.g. eg, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In another modality, the number of substitutions, deletions and / or insertions in the SEQ. ID NO: 59 is no greater than 10, e.g. eg , 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. In a further embodiment, the number of substitutions, preferably conservative substitutions, in SEQ. ID NO: 59 is no greater than 10, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In a further embodiment, the number of conservative substitutions in the sequence Amino acid changes may be minor, ie, conservative amino acid insertions or substitutions that do not significantly affect protein folding and / or activity; small deletions, usually 1-30 amino acids; small extensions at the amino terminus or carboxy terminus, such as a methionine residue at the amino terminus; a small linker peptide of up to 20-25 residues; or a small stretch that facilitates purification by changing net charge or other function, such as a polyhistidine region, antigenic epitope, or binding domain. Examples of conservative substitutions are within the groups of basic amino acids (arginine, lysine, and histidine), acidic amino acids (glutamic acid, and 121 aspartic), polar amino acids (glutamine and asparagine), hydrophobic amino acids (leucine, isoleucine and valine), aromatic amino acids (phenylalanine, tryptophan and tyrosine) and small amino acids (glycine, alanine, serine, threonine and methionine). Amino acid substitutions that do not generally alter specific activity are known in the art and are described, for example, in H. Neurath and R.L. Hill, 1979, in, The Proteins, Academic Press, New York. Some common substitutions are Ala / Ser, Val / Ile, Asp / Glu, Thr / Ser, Ala / Gly, Ala / Thr, Ser / Asn, Ala / Val, Ser / Gly, Tyr / Phe, Ala / Pro, Lys / Arg, Asp / Asn, Leu / Ile, Leu / Val, Ala / Glu and Asp / Gly. The essential amino acids of a polypeptide can be identified according to procedures known in the art, such as site-directed mutagenesis or alanine scanning mutagenesis (Cunningham and Wells, 1989, Science 244: 1081-1085). In the latter technique, single alanine mutations are introduced at each residue in the molecule, and the resulting mutated molecules are tested for muramidase activity to identify amino acid residues that are crucial to the activity of the molecule. See also, Hilton et al., 1996, J. Biol. Chem. 271: 4699-4708. The active site of the enzyme or other biological interaction can also be determined by physical analysis of the structure, determined by 122 techniques such as nuclear magnetic resonance, crystallography, electron diffraction, or photoaffinity labeling, along with mutation of putative contact site amino acids. See, for example, de Vos et al., 1992, Science 255: 306-312; Smith et al., 1992, J. Mol. Biol. 224: 899-904; Wlodaver et al., 1992, FEBS Lett. 309: 59-64. The identity of the essential amino acids can also be deduced from an alignment with a related polypeptide. The crystal structure of the muramidase CBS114.92 from Acremonium alcalophilum was solved at a resolution of 1.3 Á as disclosed in WO 2013 / 076253. These atomic coordinates can be used to generate a three-dimensional model illustrating the structure of the Acremonium alcalophilum muramidase CBS114.92 or homologous structures (such as variants of the present invention). Using the x-ray structure, residues D95 and E97 were identified as catalytic residues. In a preferred embodiment, the invention relates to a method for improving dry matter digestibility (DMd) and / or volatile fatty acid (VEA) production and / or meat production and / or milk production of a ruminant comprising administering to the ruminant a ruminant feed, a ruminant feed supplement or a ruminant feed additive comprising one or more i nnann / nznz / E / YiAi 123 muramidases, where: (a) Muramidase is or can be obtained from the phylum Ascomycota and is administered at a level of 1 to 200 mg enzyme protein per kg dry matter (DM) of ruminant feed; (b) the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, livestock, buffalo, calf, goat, sheep, lamb, deer, yak, camel, and llama; (c) dry matter digestibility (DMd) and / or volatile fatty acid (VFA) production and / or meat production and / or milk production is improved by at least 1% compared to a control ; and (d) optionally, the muramidase is administered to the ruminant daily for at least 30 days during the ruminant's lifetime. In one embodiment, the method is provided for rearing ruminants. In one embodiment, the method is provided to dairy cattle. In a further embodiment, the method is provided to dairy cattle during lactation. In one embodiment, the method is provided to livestock in the growth phase of livestock production. In one embodiment, the method is provided to livestock at the finish phase of livestock production. In one modality, milk production corrected for i nnann / nznz / E / YiAi 124 energy (ECM) is improved by at least 1.25%, such as by at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another mode, ECM production improves by 1% to 5%, such as 1% to 4%, 1% to 3%, 1.25% to 2.5%, or 1.5%. % and 2% compared to control or any combination of these ranges. In one embodiment, rumen dry matter (DMd) digestibility is improved by at least 1%, such as by at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another modality, the digestibility of dry matter is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5% or a 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and any combination thereof. In a further embodiment, the volatile fatty acid (VFA) is selected from acetate, propionate, butyrate, and any combination thereof. In a still further embodiment, the volatile fatty acid (VFA) is acetate and / or propionate. In one embodiment of the method, the volatile fatty acid (VFA) is improved by at least 1%, such as by at least 1.5%, i nnann / nznz / E / YiAi 125 at least 1.75% or at least 2.0% compared to the control. In another embodiment, the volatile fatty acid is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5% or 2%. and 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is acetate. In a further embodiment, the acetate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, the acetate is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and a 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is propionate. In a further embodiment, the propionate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, propionate improves by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, muramidase is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed, such as 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, from 5 to 75mg, from 5 to 50mg, from 5 to 40mg, 126 10 to 50 or 5 to 25 mg enzyme protein per kg DM of ruminant feed or any combination of these ranges. In one embodiment, the muramidase is administered to the ruminant using one of the regimens disclosed herein. In another preferred embodiment, the invention relates to a method for improving dry matter digestibility (DMd) and / or volatile fatty acid (VFA) production and / or meat production and / or milk production of a ruminant comprising administering to the ruminant a ruminant feed, a ruminant feed supplement or a ruminant feed additive comprising one or more muramidases, wherein: (a) the muramidase is a GH24 muramidase which is or can be obtained from the phylum Ascomycota and is administered at a level of 1 to 200 mg enzyme protein per kg DM of the ruminant feed; (b) the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, livestock, buffalo, calf, goat, sheep, lamb, deer, yak, camel, and llama; (c) dry matter digestibility (DMd) and / or volatile fatty acid (VFA) production and / or meat production and / or milk production is improved by at least 1% i nnann / nznz / E / YiAi 127 compared to a control; and (d) optionally, the muramidase is administered to the ruminant daily for at least 30 days during the ruminant's lifetime. In one embodiment, the method is provided for rearing ruminants. In one embodiment, the method is provided to dairy cattle. In a further embodiment, the method is provided to dairy cattle during lactation. In one embodiment, the method is provided to livestock in the growth phase of livestock production. In one embodiment, the method is provided to livestock at the completion stage of livestock production. In one embodiment of the method, energy corrected milk production (ECM) is improved by at least 1.25%, such as by at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another mode, ECM production improves by 1% to 5%, such as 1% to 4%, 1% to 3%, 1.25% to 2.5%, or 1.5%. % and 2% compared to control or any combination of these ranges. In one embodiment of the method, rumen dry matter (DMd) digestibility is improved by at least 1%, such as by at least 1.5%, at least 1.75% or at least 2.0% compared to the control. In another modality, the digestibility of the dry matter improves between 1% and i nnann / nznz / E / YiAi 128 15%, such as 1-10%, 1-7%, 1-5%, or 2-5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and any combination thereof. In a further embodiment, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, and any combination thereof. In a still further embodiment, the volatile fatty acid (VEA) is acetate and / or propionate. In one embodiment of the method, volatile fatty acid (VEA) is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to the control. In another embodiment, the volatile fatty acid is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2%. and 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is acetate. In a further embodiment, the acetate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, the acetate is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and a 5% compared to control or 129 any combination of these intervals. In one embodiment of the method, the volatile fatty acid (VEA) is propionate. In a further embodiment, the propionate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, propionate improves by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, muramidase is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed, such as 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 to 75 mg, 5 to 50 mg, 5 to 40 mg, 10 to 50 or 5 to 25 mg of enzyme protein per kg DM of ruminant feed or any combination of these ranges. In one embodiment of the method, the muramidase is administered to the ruminant using one of the regimens disclosed herein. In another preferred embodiment, the invention relates to a method for improving dry matter digestibility (DMd) and / or volatile fatty acid (VEA) production and / or meat production and / or milk production of a ruminant comprising administering to the ruminant a ruminant feed, a ruminant feed supplement or an i nnann / nznz / E / YiAi 130 feed additive for ruminants comprising one or more muramidases, wherein: (a) the muramidase is a GH25 muramidase which is or can be obtained from the phylum Ascomycota and is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed; (b) the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, livestock, buffalo, calf, goat, sheep, lamb, deer, yak, camel, and llama; (c) dry matter digestibility (DMd) and / or volatile fatty acid (VFA) production and / or meat production and / or milk production is improved by at least 1% compared to a control ; and (d) optionally, the muramidase is administered to the ruminant daily for at least 30 days during the ruminant's lifetime. In one embodiment, the method is provided for rearing ruminants. In one embodiment, the method is provided to dairy cattle. In a further embodiment, the method is provided to dairy cattle during lactation. In one embodiment, the method is provided to livestock in the growth phase of livestock production. In one embodiment, the method is provided to livestock at the finish phase of livestock production. i nnann / nznz / E / YiAi 131 In one embodiment of the method, energy corrected milk production (ECM) is improved by at least 1.25%, such as by at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another mode, ECM production improves by 1% to 5%, such as 1% to 4%, 1% to 3%, 1.25% to 2.5%, or 1.5%. % and 2% compared to control or any combination of these ranges. In one embodiment of the method, rumen dry matter (DMd) digestibility is improved by at least 1%, such as by at least 1.5%, at least 1.75% or at least 2.0% compared to the control. In another modality, the digestibility of dry matter is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5% or a 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, muramidase is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed, such as 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 to 75 mg, 5 to 50 mg, 5 to 40 mg, 10 to 50 or 5 to 25 mg of enzyme protein per kg of ruminant feed or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is selected from among acetate, propionate, butyrate, i nnann / nznz / E / YiAi 132 isobutyrate, valerate, isovalerate, and any combination thereof. In a further embodiment, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, and any combination thereof. In a still further embodiment, the volatile fatty acid (VEA) is acetate and / or propionate. In one embodiment of the method, volatile fatty acid (VEA) is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to the control. In another embodiment, the volatile fatty acid is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2%. and 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is acetate. In a further embodiment, the acetate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, the acetate is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and a 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is propionate. In a further embodiment, propionate is improved by at least 1%, such as by at least 1.5%, at least 1.75%, or at least 2.0% compared to i nnann / nznz / E / YiAi 133 control. In another embodiment, propionate improves by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, the muramidase is administered to the ruminant using one of the regimens disclosed herein. In another preferred embodiment, the invention relates to a method for improving dry matter digestibility (DMd) and / or volatile fatty acid (VFA) production and / or meat production and / or milk production of a ruminant comprising administering to the ruminant a ruminant feed, a ruminant feed supplement or a ruminant feed additive comprising one or more muramidases, wherein: (a) muramidase is a novel MUR polypeptide having muramidase activity that is or can be obtained from the phylum Ascomycota and is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed; (b) the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, livestock, buffalo, calf, goat, sheep, lamb, deer, yak, camel, and llama; (c) dry matter digestibility (DMd) and / or volatile fatty acid (VFA) production and / or i nnann / nznz / E / YiAi production 134 meat and / or milk production improves by at least 1% compared to a control; and (d) optionally, the muramidase is administered to the ruminant daily for at least 30 days during the ruminant's lifetime. In one embodiment, the method is provided for rearing ruminants. In one embodiment, the method is provided to dairy cattle. In a further embodiment, the method is provided to dairy cattle during lactation. In one embodiment, the method is provided to livestock in the growth phase of livestock production. In one embodiment, the method is provided to livestock at the finish phase of livestock production. In one embodiment of the method, energy corrected milk production (ECM) is improved by at least 1.25%, such as by at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another mode, ECM production improves by 1% to 5%, such as 1% to 4%, 1% to 3%, 1.25% to 2.5%, or 1.5%. % and 2% compared to control or any combination of these ranges. In one embodiment of the method, rumen dry matter (DMd) digestibility is improved by at least 1%, such as by at least 1.5%, at least 1.75% or at least 2.0% compared to the control. In another modality, the i nnann / nznz / E / YiAi 135 digestibility of dry matter improves by between 1% and 15%, such as between 1% and 10%, between 1% and 7%, 1% and 5% or 2% and a 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and any combination thereof. In a further embodiment, the volatile fatty acid (VEA) is selected from acetate, propionate, butyrate, and any combination thereof. In a still further embodiment, the volatile fatty acid (VFA) is acetate and / or propionate. In one embodiment of the method, volatile fatty acid (VFA) is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to the control. In another embodiment, the volatile fatty acid is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2%. and 5% compared to control or any combination of these intervals. In one embodiment of the method, the volatile fatty acid (VFA) is acetate. In a further embodiment, the acetate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, the acetate is improved by 1% to 15%, such as 1% to 10%, 1% to 7%, 136 1% and 5% or 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, the volatile fatty acid (VEA) is propionate. In a further embodiment, the propionate is improved by at least 1%, such as at least 1.5%, at least 1.75%, or at least 2.0% compared to control. In another embodiment, propionate improves by 1% to 15%, such as 1% to 10%, 1% to 7%, 1% to 5%, or 2% and 5% compared to control or any combination of these ranges. In one embodiment of the method, muramidase is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed, such as 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 to 75 mg, 5 to 50 mg, 5 to 40 mg, 10 to 50 or 5 to 25 mg of enzyme protein per kg of DM ruminant feed or any combination of these ranges. In one embodiment of the method, the muramidase is administered to the ruminant using one of the regimens disclosed herein. formulation agent The enzyme of the invention can be formulated as a liquid or a solid. For a liquid formulation, the formulating agent may comprise a polyol (such as for example glycerol, ethylene glycol or propylene glycol), an i nnann / nznz / E / YiAi salt 137 (such as for example sodium chloride, sodium benzoate, potassium sorbate) or a sugar or sugar derivative (such as for example dextrin, glucose, sucrose, and sorbitol). Thus in one embodiment, the composition is a liquid composition comprising the polypeptide of the invention and one or more formulating agents selected from the list consisting of glycerol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, sodium chloride , sodium benzoate, potassium sorbate, dextrin, glucose, sucrose, and sorbitol. The liquid formulation can be sprayed on the feed after it has been pelleted or added to the drinking water provided to the ruminants. For a solid formulation, the formulation can be, for example, as a granule, pellet or spray-dried powder. The formulation agent may comprise a salt (organic or inorganic zinc, sodium, potassium or calcium salts such as, eg, calcium acetate, calcium benzoate, calcium carbonate, calcium chloride, calcium citrate, calcium sorbate , calcium sulfate, potassium acetate, potassium benzoate, potassium carbonate, potassium chloride, potassium citrate, potassium sorbate, potassium sulfate, sodium acetate, sodium benzoate, sodium carbonate, sodium chloride, citrate Sodium, Sodium Sulfate, Zinc Acetate, Zinc Benzoate, Zinc Carbonate, Zinc Chloride, Zinc Citrate, Sorbate 138 zinc, zinc sulfate), starch or a sugar or sugar derivative (such as, eg, sucrose, dextrin, glucose, lactose, sorbitol). In one embodiment, the solid composition is in granular form. The granule may have a matrix structure, where the components are mixed homogeneously. However, the granule typically comprises a core particle and one or more coatings, which are typically salt and / or wax coatings. Examples of waxes are polyethylene glycols; polypropylenes; Carnauba wax; Candelilla wax; Bee wax; hydrogenated vegetable oil or ruminant tallow, such as hydrogenated bovine tallow, hydrogenated palm oil, hydrogenated cottonseed and / or hydrogenated soybean oil; fatty acid alcohols; monoglycerides and / or diglycerides, such as glyceryl stearate, where the stearate is a mixture of stearic and palmitic acid; microcrystalline wax; paraffin; and fatty acids, such as hydrogenated straight long chain fatty acids and derivatives thereof. A preferred wax is palm oil or hydrogenated palm oil. The core particle can be either a homogeneous mixture of muramidase of the invention optionally combined with one or more additional enzymes and optionally together with one or more salts or a particle inert with the muramidase of the invention optionally combined with one or more i nnan enzymes. / nznz / E / YiAi 139 additional applied on this. In one embodiment, the core particle material is selected from the group consisting of inorganic salts (such as calcium acetate, calcium benzoate, calcium carbonate, calcium chloride, calcium citrate, calcium sorbate, calcium sulfate , potassium acetate, potassium benzoate, potassium carbonate, potassium chloride, potassium citrate, potassium sorbate, potassium sulfate, sodium acetate, sodium benzoate, sodium carbonate, sodium chloride, sodium citrate, sulfate sodium, zinc acetate, zinc benzoate, zinc carbonate, zinc chloride, zinc citrate, zinc sorbate, zinc sulfate), starch or a sugar or sugar derivative (such as, for example, sucrose, dextrin , glucose, lactose, sorbitol), sugar or sugar derivative (such as, for example, sucrose, dextrin, glucose, lactose, sorbitol), small organic molecules, starch, flour, cellulose, and minerals and clay minerals (also known as phyllosilicates hydrated aluminum). In a preferred embodiment, the core comprises a clay mineral, such as kaolinite or kaolin. The salt coating normally has a thickness of at least 1 pm and can be a particular salt or a mixture of salts, such as Na2SO4, K2SO4, MgSO4 and / or sodium citrate. Other examples are those described in, p. e.g., WO 2008 / 017659, WO 2006 / 034710, WO 1997 / 05245, WO i nnann / nznz / E / YiAi 140 1998 / 54980, WO 1998 / 55599, WO 2000 / 70034 or a polymer coating such as that described in WO 2001 / 00042. In another embodiment, the composition is a solid composition comprising the muramidase of the invention and one or more formulating agents selected from the list consisting of sodium chloride, sodium benzoate, potassium sorbate, sodium sulfate, potassium sulfate , magnesium sulfate, sodium thiosulfate, calcium carbonate, sodium citrate, dextrin, glucose, sucrose, sorbitol, lactose, starch and cellulose. In a preferred embodiment, the formulation agent is selected from one or more of the following compounds: sodium sulfate, dextrin, cellulose, sodium thiosulfate, and calcium carbonate. In a preferred embodiment, the solid composition is in granular form. In one embodiment, the solid composition is in granular form and comprises a core particle, an enzyme layer comprising the muramidase of the invention, and a salt coating. In a further embodiment, the formulation agent is selected from one or more of the following compounds: glycerol, ethylene glycol, 1,2-propylene glycol or 1,3-propylene glycol, sodium chloride, sodium benzoate, potassium sorbate, sodium sulfate, Potassium Sulfate, Magnesium Sulfate, Sodium Thiosulfate, Calcium Carbonate, Innan / nznz / E / YiAi Citrate 141 sodium, dextrin, glucose, sucrose, sorbitol, lactose, starch, kaolin, and cellulose. In a preferred embodiment, the formulation agent is selected from one or more of the following compounds: 1,2-propylene glycol, 1,3-propylene glycol, sodium sulfate, dextrin, cellulose, sodium thiosulfate, kaolin, and calcium carbonate. Ruminant feed, ruminant feed supplement and ruminant feed additives A ruminant feed composition or component according to the invention has a crude protein content of between 50 and 800 g / kg and further comprises one or more polypeptides having muramidase activity as described herein. In addition or as an alternative (to the crude protein content indicated above), the ruminant feed composition of the invention has a metabolizable energy content of 5-30 MJ / kg. In particular embodiments, the content of metabolizable energy, crude protein, calcium and / or phosphorus is within any one of intervals 2, 3, 4 or 5 in table B of document WO 2001 / 058275 (R. 2-5 ) . In particular embodiments, the ruminant feed comprises non-protein nitrogen obtained from, for example, urea. i nnann / nznz / E / YiAi The nitrogen content is determined by the 142 Kjeldahl method (A.O.A.C., 1984, Official Methods of Analysis 14.aed., Association of Official Analytical Chemists, Washington DC) and crude protein is calculated as nitrogen (N) multiplied by a factor of 6.25 (i.e. crude protein (g / kg) = N(g / kg) x 6.25). Metabolizable energy can be calculated based on the NRC Publication Ruminant Nutrient Requirements, Seventh Edition Revised 2001, Subcommittee on Ruminant Nutrition, Board of Agriculture, National Research Council. National Academy Press, Washington, D.C., pp. 2-6. In one embodiment, the ruminant feed composition of the invention contains at least one vegetable protein as defined above. The ruminant feed composition of the invention may also contain distiller's dried grains with solubles (DDGS), typically in amounts of 0-30%. In other additional particular embodiments, the ruminant feed composition of the invention contains 0-80% corn; and / or 0-80% sorghum; and / or 0-70% wheat; and / or 0-70% barley; and / or 0-30% oats; and / or 0-40% soybean meal; and / or 0-20% whey. The ruminant feed may comprise vegetable proteins. In particular modalities, the protein content of vegetable proteins is at least 10, 20, 30, 40, i nnann / nznz / E / YiAi 143, 60, 70, 80 or 90% (p / p). Vegetable proteins can be obtained from vegetable protein sources, such as legumes and cereals, for example, plant materials from the families Fabaceae (Leguminosae), Cruelferaceae, Chenopodiaceae and Poaceae, such as soybean meal, lupine meal, rapeseed meal. and combinations thereof. In a particular embodiment, the vegetable protein source is material from one or more plants of the Fabaceae family, for example, soybean, lupine, pea or bean. In another particular modality, the vegetable protein source is a material from one or more plants of the Chenopodiaceae family, for example, beets, sugar beets, spinach or quinoa. Other examples of vegetable protein sources are rapeseed and cabbage. In another particular embodiment, soy is a preferred vegetable protein source. Other examples of vegetable protein sources are cereals such as barley, wheat, rye, oats, corn, rice and sorghum. In a particular embodiment, forage plants, such as corn, legumes, and grasses that have been cut and stored anaerobically and fermented for preservation. This is known as silage and can make up as much as 90% of the cattle diet. In a particular embodiment, non-protein nitrogen (NPN) sources may form part of the diet. An example is 144 urea, which represents up to 25% of the total crude protein in cattle diets. The ruminant concentrate comprising various feeds can be manufactured, for example, as ground feed (not pelleted) or pelleted feed. Ground feeds are normally mixed and sufficient amounts of essential vitamins and minerals are added according to the specifications for the species in question. Enzymes can be added as liquid or solid enzyme formulations. For example, for ground feed, a solid or liquid enzyme formulation may be added before or during the ingredient mixing step. For pelleted feeds, the muramidase / enzyme preparation (liquid or solid) can also be added before or during the passage of feed ingredients. Typically a liquid enzyme preparation comprises the muramidase of the invention optionally with a polyol, such as glycerol, ethylene glycol or propylene glycol and added after the pelleting step, such as by spraying the liquid formulation onto the pellets. Muramidase can also be incorporated into a feed supplement, feed additive, or premix. Alternatively, the protease can be prepared by freezing a mixture of liquid enzyme solution with a thickening agent such as ground soybean meal and 145 then lyophilizing the mixture. In one embodiment, the composition comprises one or more additional enzymes. In one embodiment, the composition comprises one or more microbes. In one embodiment, the composition comprises one or more vitamins. In one embodiment, the composition comprises one or more minerals. In one embodiment, the composition comprises one or more amino acids. In one embodiment, the composition comprises one or more other feed components. In another embodiment, the composition comprises one or more of the polypeptides of the invention, one or more formulating agents, and one or more additional enzymes. In one embodiment, the composition comprises one or more of the polypeptides of the invention, one or more formulating agents, and one or more microbes. In one embodiment, the composition comprises one or more of the polypeptides of the invention, one or more formulating agents, and one or more vitamins. In one embodiment, the composition comprises one or more of the polypeptides of the invention and one or more minerals. In one embodiment, the composition comprises the polypeptide of the invention, one or more formulating agents, and one or more amino acids. In one embodiment, the composition comprises one or more of the polypeptides of the invention, one or more formulating agents, and one or more other feed components. i nnann / nznz / E / YiAi 146 In a further embodiment, the composition comprises one or more of the polypeptides of the invention, one or more formulating agents, and one or more components selected from the list consisting of: one or more additional enzymes; one or more microbes; one or more vitamins; one or more minerals; one or more amino acids; and one or more other feed components. The final concentration of muramidase in the diet is within the range of 0.01 to 200 mg enzyme protein per kg DM of feed for ruminants, such as 0.1 to 150 mg, 0.5 to 100 mg, 1 to 75 mg, 2 to 50 mg, 3 to 25 mg, 2 to 80 mg, 5 to 60 mg, 8 to 40 mg or 10 to 30 mg of enzyme protein per kg DM of ruminant feed or any combination of these intervals. It is currently contemplated that muramidase be administered in one or more of the following amounts (dosage ranges): 0.01-200; 0.01-100; 0.5-100; 1-50; 5-100; 550; 10-100; 0.05-50; 5-25; or 0.10-10 - being all these intervals in mg of muramidase per kg of DM of feed (ppm). To determine the mg of muramidase protein per kg DM of feed, the muramidase is purified from the feed composition and the specific activity of the purified muramidase is determined using a relevant assay (see below for muramidase activity). The muramidase activity of the feed composition as such is also determined i nnann / nznz / E / YiAi 147 using the same assay and, based on these two determinations, the dose in mg of muramidase protein per kg of feed is calculated. In one embodiment, the ruminant feed additive of the invention is intended to be included (or is prescribed to be included) in ruminant diets or feeds at levels of 0.01 to 10.0%; more particularly, from 0.05 to 5.0%; or from 0.2 to 1.0% (% refers to g of additive per 100 g of feed). This is so in particular for premixes. The same principles apply to determine the mg of muramidase protein in the feed supplement and feed additives. Of course, if a sample of the muramidase used to prepare the feed additive or feed is available, the specific activity is determined from this sample (it is not necessary to purify the muramidase from the feed composition, feed supplement or the feed additive). additional enzymes In another embodiment, the compositions described herein optionally include one or more enzymes. Enzymes can be classified based on the NC-IUBMB enzyme nomenclature manual, 1992), see also the ΕΝΖΥΜΕ page on the internet: http: / / www.expasy.ch / enzyme / . ΕΝΖΥΜΕ is a repository of information related to enzyme nomenclature. It is mainly based on the 148 recommendations of the International Union of Biochemistry and Molecular Biology (IUB-MB) nomenclature committee, Academic Press, Inc., 1992 and describes each type of characterized enzyme for which an EC (Enzyme Commission) number has been provided (Bairoch A. The ΕΝΖΥΜΕ database, 2000, Nucleic Acids Res 28:304-305). This nomenclature of MB-IUB enzymes is based on their substrate specificity and occasionally their molecular mechanism; such a classification does not reflect the structural features of these enzymes. Another classification of certain glycoside hydrolase enzymes, such as endoglucanase, xylanase, galactanase, mannanase, dextranase, muramidase, and galactosidase, is described in Henrissat et al., The carbohydrate-active enzymes database (CAZy) in 2013, Nucí. Acids Res. (2014 Jan 1) 42 (DI): D490-D495; see also www.cazy.org. Therefore, the composition of the invention may also comprise at least one other enzyme selected from the group comprising xylanase (EC 3.2.1.8); galactanase (EC 3.2.1.89); alpha-galactosidase (EC 3.2.1.22); protease (EC 3.4); phospholipase Al (EC 3.1.1.32); phospholipase A2 (EC 3.1.1.4); lysophospholipase (EC 3.1.1.5); phospholipase C (3.1.4.3); phospholipase D (EC 3.1.4.4); amylase such as, for example, alpha-amylase (EC 3.2.1.1); arabinofuranosidase (EC 3.2.1.55); beta-xylosidase (EC 3.2.1.37); acetyl xylan esterase (EC 149 3.1.1.72); feruloyl esterase (EC 3.1.1.73); cellulase (EC 3.2.1.4); cellobiohydrolases (EC 3.2.1.91); beta-glucosidase (EC 3.2.1.21); pullulanase (EC 3.2.1.41), alpha-mannosidase (EC 3.2.1.24), mannanase (EC 3.2.1.25) and beta-glucanase (EC 3.2.1.4 or EC 3.2.1.6), or any combination thereof. In a particular embodiment, the composition of the invention comprises a phytase (EC 3.1.3.8 or 3.1.3.26). Examples of commercially available phytases include Bio-Feed™ phytase (Novozymes), RONOZYME® P, RONOZYME® NP and RONOZYME® HiPhos (DSM Nutritional Products), Natuphos™ (BASF), Finase® and Quantum® Blue (AB Enzymes) , OptiPhos® (Huvepharma) Phyzyme® XP (Verenium / DuPont) and Axtra® PHY (DuPont). Other preferred phytases include those described in, for example, WO 98 / 28408, WO 00 / 43503, and WO 03 / 066847. In a particular embodiment, the composition of the invention comprises a xylanase (EC 3.2.1.8). Examples of commercially available xylanases include Ronozyme® WX and Ronozyme® G2 (DSM Nutritional Products), Econase® XT and Barley (AB Vista), Xylathin® (Verenium), Hostazym® X (Huvepharma), and Axtra® XB (xylanase / beta-glucanase, DuPont). In a particular embodiment, the composition of the invention comprises a protease (EC 3.4). Examples of commercially available proteases include Ronozyme® ProAct (DSM Nutritional Products). In a particular modality, the composition of the 150 invention comprises an alpha-amylase (EC 3.2.1.1). Examples of commercially available alpha-amylases include Ronozyme® Rumistar (DSM Nutritional Products). microbes In one embodiment, the ruminant feed composition further comprises one or more additional microbes. In a particular embodiment, the ruminant feed composition further comprises a bacterium of one or more of the following genera: Lactobacillus, Lactococcus, Streptococcus, Bacillus, Pediococcus, Enterococcus, Leuconostoc, Carnobacterium, Propionibacterium, Bifidobacterium, Clostridium and Megasphaera or any combination of these. In a preferred embodiment, the ruminant feed composition further comprises a bacterium of one or more of the following strains: Bacillus subtilis, Bacillus licheniformis, Bacillus amyloliquefaciens, Bacillus cereus, Bacillus pumilus, Bacillus polymyxa, Bacillus megaterium, Bacillus coagulans, Bacillus circulans, Enterococcus faecium, Enterococcus spp, and Pediococcus spp, Lactobacillus spp, Bifidobacterium spp, Lactobacillus acidophilus, Pediococsus acidilactici, Lactococcus lactis, Bifidobacterium bifidum, Propionibacterium thoenii, Lactobacillus farciminus, lacto bacillus rhamnosus, Clostridium butyricum, Bifidobacterium animalis ssp. animalis, Lactobacillus 151 reateri, salivary Lactobacillas ssp. spittlebugs, Megasphaera elsdenii, Propionibacteria sp. In a more preferred embodiment, the composition, ruminant feed supplement, ruminant feed additive or ruminant feed comprises a bacterium selected from one or more of the following strains: Enterococcas faecium strain 8G-1 (NRRL B- 50173), Enterococcas faeciam strain 8G-73 (NRRL B-50172), Badilas pamilas strain 8G-134 (NRRL B-50174), M. elsdenii strain NCIMB 41125, Propionibacteriam strain B169 (PTA-5271), Propionibacteriam strain P170 (PTA-5272), Propionibacteriam strain P179 (NRRL B-50133), Propionibacteriam strain P195 (NRRL B-50132), Propionibacteriam strain P261 (NRRL B-50131), Propionibacteria jensenii strain P63 (DSM22192), Propionibacteriam strain P5 (ATCC 55467), Propionibacteriam strain P54 (NRRL B-50494), Propionibacteriam strain P25 (NRRL B50497), Propionibacteriam strain P49 (NRRL B-50496), Propionibacteriam strain P104 (NRRL B-50495), B. licheniformis strain 3-12a (NRRL B-50504), B. sabtilis strain 4-7d (NRRL B50505), B. licheniformis strain 4-2a (NRRL B-50506), B. sabtilis strain 3-5h (NRRL B-50507), Badilas 747 (NRRL B67257) or a strain having all of the identifying characteristics of Badilas 747 (NRRL B-67257), Badilas strain 1104 (NRRL B-67258), Badilas strain 1781 (NRRL B-67259), Badilas strain 1541 (NRRL B-67260), Badilas strain 2018 (NRRL 152 B-67261) and Bacillus strain 1999 (NRRL B-67318). In a more preferred embodiment, the composition, ruminant feed supplement, ruminant feed additive or ruminant feed further comprises a bacterium of one or more of the following Bacillus subtilis strains: 3A-P4 (PTA-6506 ), 15A-P4 (PTA-6507), 22C-P1 (PTA6508), 2084 (NRRL B-500130), LSSA01 (NRRL-B-50104), BS27 (NRRL B-501 05), BS 18 (NRRL B- 50633), BS 278 (NRRL B-50634), DSM 29870, DSM 29871, NRRL B-50136, NRRL B-50605, NRRL B50606, NRRL B-50622 and PTA-7547. In a more preferred embodiment, the composition, ruminant feed supplement, ruminant feed additive or ruminant feed further comprises a bacterium of one or more of the following Bacillus pumilus strains: NRRL B-50016, ATCC 700385 , NRRL B-50885 or NRRL B50886. In a more preferred embodiment, the composition, ruminant feed supplement, ruminant feed additive or ruminant feed further comprises a bacterium of one or more of the following Bacillus lichenformis strains: NRRL B 50015, NRRL B- 50621 or NRRL B-50623. In a more preferred embodiment, the composition, ruminant feed supplement, ruminant feed additive or ruminant feed further comprises a bacterium of one or more of the following Bacillus i nnann / nznz / E / YiAi strains 153 amyloliquefaciens: DSM 2 98 69, DSM 2 98 72, NRRL B 50 607, PTA7543, PTA-7549, NRRL B-50349, NRRL B-50606, NRRL B-50013, NRRL B-50151, NRRL B-50141, NRRL B-50147 or NRRL B-50888. The bacterial count of each of the bacterial strains in the ruminant feed composition is between 1 x 104 and 1 x 1014 CFU / kg of dry matter, preferably between 1 x 106 and 1 x 1012 CFU / kg of dry matter and more preferably between 1 x 107 and 1 x 1011UFC / kg of dry matter. In a more preferred embodiment, the bacteria count of each of the bacterial strains in the ruminant feed composition is between 1 x 108 and 1 x 1010 CFU / kg of dry matter. The bacterial count of each of the bacterial strains in the feed composition for ruminants is between IxlO5 and IxlO15CFU / ruminant / day, preferably between IxlO7 and IxlO13CFU / ruminant / day and more preferably, between IxlO8 and IxlO12CFU / ruminant / day. In a more preferred embodiment, the bacterial count of each of the bacterial strains in the ruminant feed composition is between 1x109 and 1x1011CFU / ruminant / day. In another embodiment, the one or more bacterial strains are present in the form of a stable spore. premix In one embodiment, the ruminant feed may include a premix, comprising, for example, vitamins, i nnann / nznz / E / YiAi 154 minerals, enzymes, amino acids, preservatives, antibiotics, other feed components or any combination thereof that are mixed into ruminant feed. Amino acids The composition of the invention may further comprise one or more amino acids. Examples of amino acids that are used in ruminant feed are lysine, alanine, beta-alanine, threonine, methionine and tryptophan. Vitamins and minerals In another embodiment, the ruminant feed may include one or more vitamins, such as one or more fat-soluble vitamins and / or one or more water-soluble vitamins. In another embodiment, the ruminant feed may optionally include one or more minerals, such as one or more trace elements and / or one or more macrominerals. Normally fat and water soluble vitamins, as well as trace elements, are part of the so-called premix intended to be added to feed, while macroelements are usually added separately to feed. Non-limiting examples of fat soluble vitamins include vitamin A, vitamin D3, vitamin E, and vitamin K, eg, vitamin K3. Non-limiting examples of water soluble vitamins include vitamin B12, biotin and choline, vitamin Bl, vitamin B2, vitamin B6, niacin, folic acid, and i nnann / nznz / E / YiAi 155 pantothenate, eg Ca-D-pantothenate. Non-limiting examples of trace elements include boron, cobalt, chloride, chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, and zinc. Non-limiting examples of macrominerals include calcium, magnesium, potassium, and sodium. Alternatively, the ruminant feed supplement or ruminant feed additive of the invention comprises at least one of the individual components specified in Ruminant Nutrient Requirements, Seventh Revised Edition 2001, Subcommittee on Ruminant Nutrition, Council of agriculture, national research council. National Academy Press, Washington, D.C. Table A of document WO 01 / 58275. The expression at least one refers to one or more, one or two or three or four and so on up to a total of thirteen or up to a total of fifteen individual components. More specifically, this at least one individual component is included in the additive of the invention in an amount such as to provide a concentration in feed within the range indicated in column four or column five or column six of Table A. Other feed ingredients The composition of the invention may further comprise natural or synthetic coloring agents, i nnann / nznz / E / YiAi stabilizers 156 intestinal flora, pH stabilizers / pH modulators, digestibility enhancers, growth enhancer additives, aromatic / flavouring compounds, polyunsaturated fatty acids (PUFAs); essential oils, reactive oxygen generating species, antifungal peptides, antifungal polypeptides, antimicrobial peptides, fungal fermentation cultures and extracts, immunomodulatory additives, antioxidant additives, metabolic enhancers, rumen fermentation modifiers, rumen electron acceptors and catalysts, other zoological / technological additives, such as binding agents, anti-caking and coagulant agents, ammonia control agents, botanical antimicrobials, antimethanogens and / or ionophores. Examples of coloring agents include, but are not limited to, carotenoids, such as beta-carotene, astaxanthin, and lutein. Examples of gut flora stabilizers and / or pH stabilizers include, but are not limited to, live yeast or yeast cultures, such as Saccharomyces cerevisiae. Examples of digestibility enhancers include, but are not limited to, enzymes and alpha-amylase. Examples of aroma / flavor compounds include, but are not limited to, creosol, anethole, deca, undeca i nnann / nznz / E / YiAi 157 and / or dodecalactones, ionones, iron, gingerol, piperidine, propylidene phthalide, butylidene phthalide, capsaicin or tannin. Examples of polyunsaturated fatty acids include, but are not limited to, C18, C20, and C22 polyunsaturated fatty acids, such as arachidonic acid, docosahexanoic acid, eicosapentanoic acid, and gammalinoleic acid. Examples of essential oils include, but are not limited to, anise, juniper, capsicum, cinnamon, clove, dill, garlic, eugenol or cinnamaldehyde and their active ingredients. Examples of reactive oxygen generating species include, but are not limited to, chemical agents such as perborate, persulfate, or percarbonate; and enzymes, such as an oxidase, an oxygenase or a synthetase, arachidonic acid, docosahexanoic acid, eicosapentanoic acid and gamma-linoleic acid. Examples of antifungal polypeptides (AFPs) include, but are not limited to, the Aspergillus giganteas and Aspergillus niger peptides, as well as variants and fragments thereof that retain antifungal activity, as disclosed in WO 94 / 01459 and WO 02 / 090384. Examples of stabilizing agents, such as, for example, buffers and / or acidifiers include, but are not limited to, live yeast, sodium bicarbonate, innann / nznz / E / YiAi seaweed. 158 marine calcareous and lecithins. Examples of antimicrobial peptides (AMPs) include, but are not limited to, CAP18, leukokin A, trypticin, protegrin-1, thanatin, defensin, lactoferrin, lactoferricin, and ovispirin, such as novispirin (Robert Lehrer, 2000), plectasins, statins, including the compounds and polypeptides disclosed in the documents WO 03 / 044049 and WO 03 / 048148, as well as variants or fragments of the above that retain antimicrobial activity. Examples of immunomodulatory agents include, but are not limited to, B-glucans, Saccharomyces cerevisiae. Examples of antioxidant agents include, but are not limited to, vitamins A, E, and other natural antioxidants, eg, lecithin. Examples of electron accepting agents include, but are not limited to, nitrate and its organic compounds. Examples of fungal fermentation extracts and cultures include, but are not limited to, Aspergillus oryzae, marketed as Amaferm Vitaferm (Biozyme Enterprises, Inc.). Examples of binding and anti-caking agents include, but are not limited to, synthetic calcium aluminates. Examples of zootech additives include, by i nnann / nznz / E / YiAi 159 example, ammonia control. Examples of ionophores include monensins, such as, for example, Rumensin ® from Elanco. The composition of the invention may further comprise at least one amino acid. Examples of amino acids that are used in ruminant feed include, but are not limited to, lysine, alanine, beta-alanine, threonine, methionine, and tryptophan. Use of muramidase to improve ruminant performance In another aspect, the invention relates to the use of a ruminant feed supplement, ruminant feed additive or ruminant feed for improving the feed conversion ratio (FCR) in a ruminant, wherein the ruminant feed , the ruminant feed supplement or ruminant feed additive comprises one or more muramidases, wherein the muramidase is administered at a level of 1 to 200 mg enzyme protein per kg MD of ruminant feed. In a preferred embodiment, the improvement is compared to a ruminant feed, ruminant feed supplement or ruminant feed additive, in which muramidase is not present (referred to herein as the negative control). In one embodiment, the FCR is improved by at least 1%, such as by at least 1.25%, at least 1.5%, at least one i nnann / nznz / E / YiAi 160 1.75% or at least 2.0% compared to the control. In another embodiment, the FCR is improved by 1% to 5%, such as 1% to 4%, 1% to 3%, 1.25% to 2.5%, 1.5%, and 2% compared to control or any combination of these ranges. In one embodiment, the muramidase is administered at a level of 1 to 200 mg enzyme protein per kg DM of ruminant feed, such as 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 at 75 mg, 5 to 50 mg, 5 to 40 mg, 10 to 50 or 5 to 25 mg of enzyme protein per kg DM of ruminant feed or any combination of these ranges. In one embodiment, the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, cattle, buffalo, calf, goat, sheep, lamb, deer, yak, camel, and llama. In a preferred embodiment, the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, beef cattle, buffalo, and calf. In a more preferred modality, the ruminant is selected from the group consisting of: bovine cattle, dairy cattle and cattle for food. In one embodiment, the muramidase is administered to the ruminant for any period of time, from birth to slaughter. In a preferred embodiment, the muramidase is provided to the ruminant on a daily basis. In an additional embodiment, the muramidase is administered to the ruminant 161 daily during the life time of the ruminant. In one embodiment, the muramidase is administered to growing ruminants. In one embodiment, the muramidase is administered to dairy cattle. In one embodiment, the muramidase is administered to dairy cattle in the growth phase of dairy cattle production. In one embodiment, the muramidase is administered to livestock at the finish phase of livestock production. In a further embodiment, the muramidase is administered to calves in the milk. In one embodiment, the muramidase is of microbial origin. In a further embodiment, the muramidase is of fungal origin. In one embodiment, the muramidase is or can be obtained from the phylum Ascomycota, as well as the subphylum Pezizomycotina. In one embodiment, the muramidase comprises one or more domains from a family of glycoside hydrolase (GH) selected from the list consisting of GH24, GH25, and novel MUR polypeptides having muramidase activity. PREFERRED MODES The following is a list of preferred embodiments encompassed by the invention: 1. A ruminant feed composition, such as a ruminant feed, ruminant feed supplement or ruminant feed additive comprising one or more i nnann / nznz / E / YiAi 162 muramidases, wherein the muramidase is in an amount sufficient for administration at a level of 1 to 200 mg enzyme protein per kg of ruminant feed. 2. The ruminant feed composition of mode 1, wherein the muramidase is administered at a level of 1 to 200 mg of enzyme protein per kg of dry matter of the ruminant feed. 3. The ruminant feed composition of mode 1 or 2, wherein muramidase is administered at a level of 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 to 75 mg, 5 to 50 mg, from 5 to 40 mg, from 10 to 50, from 5 to 25 mg of enzyme protein per kg of dry matter of feed for ruminants or any combination of these intervals. 4. The ruminant feed composition of any of modalities 1 to 3, wherein the energy-corrected milk production (ECM) of ruminants after administration is improved by at least 1.0%, preferably at least 1.5%, more preferably at least 2.0% compared to the control. 5. The composition of feed for ruminants of any of the modalities 1 to 4, where the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, livestock, buffalo, young calf, goat, sheep , lamb, deer, yak, camel and llama. i nnann / nznz / E / YiAi 163 6. The composition of feed for ruminants of any of the modalities 1 to 5, where the ruminant is selected from the group that consists of: bovine cattle, dairy cattle and livestock for sale. 7. The ruminant feed composition of any of modalities 1 to 6, wherein the muramidase is administered to the ruminant for the lifetime of the ruminant. 8. The feed composition for ruminants of any of modalities 1 to 7, wherein the muramidase is of microbial origin. 9. The ruminant feed composition of mode 8, wherein the muramidase is of fungal origin. 10. The ruminant feed composition of any of the modalities 1 to 9, wherein the muramidase is obtained or can be obtained from the Ascomycota phylum. 11. The feed composition for ruminants of any of modalities 1 to 10, wherein the muramidase is obtained or can be obtained from the Pezízomycotína subphylum. 12. The ruminant feed composition of any of modalities 1 to 11, wherein the muramidase comprises one or more domains from a family of glycoside hydrolase (GH) selected from the list consisting of GH24, GH25 and novel MUR polypeptides they have i nnann / nznz / E / YiAi muramidase activity. 164 13. The ruminant feed composition of any of modalities 1 to 12, wherein the muramidase is selected from the group consisting of: (a) a polypeptide having at least 50%, e.g. g ., at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88% , at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least at least 97%, at least 98%, at least 99%, or 100% sequence identity to an amino acid sequence selected from the group consisting of: SEQ. ID NO: 3, SEQ. ID NO: 6, SEQ. ID NO: 9, SEQ. ID NO: 12, SEQ. ID NO: 15, SEQ. ID NO: 18, SEQ. ID NO: 21, SEQ. ID NO: 24, SEQ. ID NO: 27, SEQ. ID NO: 28, SEQ. ID NO: 29, SEQ. ID NO: 30, SEQ. ID NO: 31, SEQ. ID NO: 32, SEQ. ID NO: 33, SEQ. ID NO: 34, SEQ. ID NO: 35, SEQ. ID NO: 36, SEQ. ID NO: 37, SEQ. ID NO: 38, SEQ. ID NO: 39, SEQ. ID NO: 40, SEQ. ID NO: 41, SEQ. ID NO: 42, SEQ. ID NO: 43, SEQ. ID NO: 44, SEQ. ID NO: 45, SEQ. ID NO: 46, SEQ. ID NO: 47, SEQ. ID NO: 48, SEQ. ID NO: 49, SEQ. ID NO: 50, SEQ. ID NO: 51, SEQ. ID NO: 52, SEQ. ID NO: 53, SEQ. ID NO: 54, SEQ. ID NO: 55, SEQ. ID NO: 56, SEQ. ID NO: 57, SEQ. ID NO: 58, and SEQ. ID NO: 59; (b) a variant amino acid sequence selected from the group consisting of: SEQ. ID NO: 3, 165 SEQ. ID NO: 6, SEQ. ID NO: 9, SEQ. ID NO: 12, SEQ. ID NO: 15, SEQ. ID NO: 18, SEQ. ID NO: 21, SEQ. ID NO: 24, SEQ. IDNO: 27, SEC. ID NO: 28, SEQ. ID NO: 29, SEQ. ID NO: 30, SEQ. ID NO: 31, SEC. ID NO: 32, SEQ. ID NO: 33, SEQ. ID NO: 34, SEQ. ID NO: 35, SEQ. ID NO: 36, SEQ. ID NO: 37, SEQ. ID NO:38, SEQ. ID NO: 39, SEQ. ID NO: 40, SEQ. ID NO: 41, SEQ. ID NO: 42, SEC. ID NO: 43, SEQ. ID NO: 44, SEQ. ID NO: 45, SEQ. ID NO: 46, SEC. ID NO: 47, SEQ. ID NO: 48, SEQ. ID NO: 49, SEQ. ID NO: 50, SEQ. ID NO: 51, SEQ. ID NO: 52, SEQ. ID NO:53, SEQ. ID NO: 54, SEQ. ID NO: 55, SEQ. ID NO: 56, SEQ. IDNO: 57, SEC. ID NO: 58, and SEQ. ID NO: 59 wherein the variant has muramidase activity and comprises one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in 1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions; (c) a fragment of the polypeptide of (a) or (b) having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 amino acids, or at least 200 amino acids. 14. The composition of feed for ruminants of 166 any of modalities 1 to 13, wherein the ruminant feed composition further comprises one or more components selected from the list consisting of: one or more vehicles; one or more additional enzymes; one or more microbes; one or more vitamins; one or more minerals; one or more amino acids; one or more organic acids; and one or more other feed components. 15. The ruminant feed composition of any of modalities 1 to 14, wherein the muramidase is in granulated form. 16. The feed composition for ruminants of modality 15, where the granules are coated. 17. The ruminant feed composition of embodiment 16 wherein the coating comprises a salt and / or wax and / or a flour. 18. The ruminant feed composition of any of modalities 1 to 17, wherein the muramidase is in a liquid formulation. 19. The ruminant feed composition of embodiment 18, wherein the liquid formulation is sprayed on the feed after it has been pelleted. i nnann / nznz / E / YiAi 167 20. The ruminant feed composition of any of modalities 4 to 19, wherein the control is a ruminant feed composition that does not comprise muramidase. 21. The ruminant feed composition of any of embodiments 4 to 20, wherein the control is a ruminant feed composition that does not comprise muramidase GH24, muramidase GH25, or novel MUR polypeptides having muramidase activity. 22. The ruminant feed composition of any of modalities 4 to 21, wherein the control is a ruminant feed composition comprising hen egg white lysozyme (HEWL). 23. The ruminant feed composition of any of modalities 4 to 21, wherein the control is monensin. 24. The ruminant feed composition of any of modalities 1 to 23, wherein the ruminant feed composition comprising muramidase is administered to a ruminant selected from the group consisting of: A growing ruminant, dairy cattle, cattle stock in the growth phase of stock cattle production, stock cattle in the completion phase of stock cattle production, and an i nnann / nznz / E / YiAi calf. 168 25. The ruminant feed composition of any of embodiments 1 to 24, wherein the ruminant feed composition comprising muramidase is administered to a growing ruminant. 26. The ruminant feed composition of any of modalities 1 to 24, wherein the ruminant feed composition comprising muramidase is administered to dairy cattle. 27. The ruminant feed composition of any of modalities 1 to 24, wherein the ruminant feed composition comprising muramidase is administered to livestock in the growth phase of livestock production. 28. The ruminant feed composition of any of the modalities 1 to 24, wherein the ruminant feed composition comprising muramidase is administered to beef cattle at the finishing phase of beef cattle production. 29. The ruminant feed composition of any of the embodiments 1 to 24, wherein the ruminant feed composition comprising muramidase is administered to a calf. 30. A method of improving energy-corrected milk (ECM) production of a ruminant comprising administering to the ruminant a feed composition for i nnann / nznz / E / YiAi 169 ruminants according to any of the modalities 1 to 29. 31. A method of increasing the dry matter (DMd) digestibility of a ruminant feed, ruminant feed supplement or ruminant feed additive comprising the steps of: a) providing at least one muramidase; b) provide a ruminant feed, ruminant feed supplement or ruminant feed additive suitable for a ruminant animal; c) applying the muramidase to the ruminant feed, ruminant feed supplement or ruminant feed additive to form a ruminant feed composition; and d) feeding the ruminant feed composition to the ruminant animal, whereby an increase in dry matter digestibility is effected. 32. The method according to claim 31, wherein the DMd is measured according to example 2. 33. The method of any of the embodiments 31 to 32, wherein the DMd is increased compared to the DMd in the feed prepared as in embodiment 31 but without muramidase added in step c). 34. The method of any of modalities 31 to 33, wherein volatile fatty acid (VEA) production in the rumen is increased compared to VEA production in the i nnann / nznz / E / YiAi rumen of a ruminant by that is not fed with a 170 muramidase. 35. The method of any of embodiments 31 to 34, wherein rumen propionate production is increased as compared to rumen propionate production of a ruminant not fed a muramidase. 36. The method of any of the embodiments 31 to 35, wherein rumen acetate production is increased as compared to rumen acetate production of a ruminant not fed a muramidase. 37. The method of any of the modalities 31 to 36, wherein the muramidase is administered at a level of 1 to 310 mg enzyme protein per kg dry matter of the ruminant feed. 38. The method of any of the modalities 31 to 37, wherein the muramidase is administered at a level of 5 to 150 mg, 5 to 125 mg, 5 to 100 mg, 5 to 75 mg, 5 to 50 mg, 5 to 40 mg, 10 to 50, 5 to 25 mg of enzyme protein per kg dry matter of ruminant feed or any combination of these ranges. 39. The method of any of the modalities 31 to 38, wherein the energy-corrected milk production (ECM) of the ruminants after administration improves by at least 1.0%, preferably at least 1.5%, more preferably at least 2.0% compared to the control. 40. The method of any of the modalities 31 to 39, i nnann / nznz / E / YiAi 171 wherein the ruminant is selected from the group consisting of: cattle, cows, dairy cattle, market cattle, buffalo, young calf, goat, sheep, lamb, deer, yak, camel, and llama. 41. The method of any of the modalities 31 to 40, where the ruminant is selected from the group consisting of: bovine cattle, dairy cattle and livestock for sale. 42. The method of any of the modalities 31 to 41, wherein the muramidase is administered to the ruminant during the lifetime of the ruminant. 43. The method of any of the modalities 31 to 42, wherein the muramidase is of microbial origin. 44. The method of any of the modalities 31 to 42, wherein the muramidase is of fungal origin. 45. The method of any of embodiments 31 to 44, wherein the muramidase is or can be obtained from the phylum Ascomycota. 46. ​​The method of any of embodiments 31 to 45, wherein the muramidase is or can be obtained from the Pezizomycotina subphylum. 47. The method of any of embodiments 31 to 46, wherein the muramidase comprises one or more domains from a family of glycoside hydrolase (GH) selected from the list consisting of GH24, GH25, and novel MUR i nnann / nznz polypeptides / E / YiAi 172 that have muramidase activity. 48. The method of any of the modalities 31 to 47, wherein the muramidase is selected from the group consisting of: (a) a polypeptide having at least 50%, e.g. g ., at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86%, at least one 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to an amino acid sequence selected from the group consisting of: SEQ. ID NO: 3, SEQ. ID NO: 6, SEQ. ID NO: 9, SEQ. ID NO: 12, SEQ. ID NO: 15, SEQ. ID NO: 18, SEQ. ID NO: 21, SEQ. ID NO: 24, SEQ. ID NO: 27, SEC. ID NO: 28, SEQ. ID NO: 29, SEQ. ID NO: 30, SEQ. ID NO: 31, SEC. ID NO: 32, SEQ. ID NO: 33, SEQ. ID NO: 34, SEQ. ID NO: 35, SEQ. ID NO: 36, SEQ. ID NO: 37, SEQ. ID NO:38, SEQ. ID NO: 39, SEQ. ID NO: 40, SEQ. ID NO: 41, SEQ. ID NO: 42, SEC. ID NO: 43, SEQ. ID NO: 44, SEQ. ID NO: 45, SEQ. ID NO: 46, SEC. ID NO: 47, SEQ. ID NO: 48, SEQ. ID NO: 49, SEQ. ID NO: 50, SEQ. ID NO: 51, SEQ. ID NO: 52, SEQ. ID NO:53, SEQ. ID NO: 54, SEQ. ID NO: 55, SEQ. ID NO: 56, SEQ. IDNO: 57, SEC. ID NO: 58, and SEQ. ID NO: 59; (b) a variant of an amino acid sequence 173 selected from the group consisting of: SEC. ID NO: 3, SEQ. ID NO: 6, SEQ. ID NO: 9, SEQ. ID NO: 12, SEQ. ID NO: 15, SEQ. ID NO: 18, SEQ. ID NO: 21, SEQ. ID NO: 24, SEQ. IDNO: 27, SEC. ID NO: 28, SEQ. ID NO: 29, SEQ. ID NO: 30, SEQ. ID NO: 31, SEC. ID NO: 32, SEQ. ID NO: 33, SEQ. ID NO: 34, SEQ. ID NO: 35, SEQ. ID NO: 36, SEQ. ID NO: 37, SEQ. ID NO:38, SEQ. ID NO: 39, SEQ. ID NO: 40, SEQ. ID NO: 41, SEQ. ID NO: 42, SEC. ID NO: 43, SEQ. ID NO: 44, SEQ. ID NO: 45, SEQ. ID NO: 46, SEC. ID NO: 47, SEQ. ID NO: 48, SEQ. ID NO: 49, SEQ. ID NO: 50, SEQ. ID NO: 51, SEQ. ID NO: 52, SEQ. ID NO:53, SEQ. ID NO: 54, SEQ. ID NO: 55, SEQ. ID NO: 56, SEQ. IDNO: 57, SEC. ID NO: 58, and SEQ. ID NO: 59 wherein the variant has muramidase activity and comprises one or more amino acid substitutions and / or one or more amino acid deletions and / or one or more amino acid insertions or any combination thereof in 1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions; (c) a fragment of the polypeptide of (a) or (b) having muramidase activity, wherein the fragment comprises at least 170 amino acids, such as at least 175 amino acids, at least 177 amino acids, at least 180 amino acids, at least 185 amino acids, at least 190 amino acids, at least 195 i nnann / nznz / E / YiAi amino acids or at least 200 amino acids. 174 49. The method of any of the modalities 31 to 48, wherein the muramidase is in a granulated form. 50. The method of mode 49, wherein the granulate is coated. 51. The method of mode 50, wherein the coating comprises a salt and / or wax and / or a flour. 52. The method of any of the modalities 31 to 51, wherein the muramidase is in a liquid formulation. 53. The method of mode 52, where the liquid formulation is sprayed on the feed after it has been pelleted. 54. The method of any of embodiments 39 to 53, wherein the control is a ruminant feed composition that does not comprise muramidase. 55. The method of any of embodiments 39 to 53, wherein the control is a ruminant feed composition that does not comprise muramidase GH24, muramidase GH25, or novel MUR polypeptides having muramidase activity. 56. The method of any of embodiments 39 to 55, wherein the control is a ruminant feed composition comprising hen egg white lysozyme (HEWL). 57. The method of any of the modalities 39 to 55, i nnann / nznz / E / YiAi where the control is monensin. 175 58. The method of any of the modalities 31 to 57, wherein the ruminant feed composition comprising muramidase is administered to a ruminant selected from the group consisting of: A growing ruminant, dairy cattle, dairy cattle in the the growth phase of the production of cattle for slaughter, cattle for slaughter in the phase of completion of the production of cattle for slaughter and a calf. 59. The method of any of embodiments 31 to 58, wherein the ruminant feed composition comprising muramidase is administered to a growing ruminant. 60. The method of any of the embodiments 31 to 58, wherein the ruminant feed composition comprising muramidase is administered to dairy cattle. 61. The method of any of the embodiments 31 to 58, wherein the ruminant feed composition comprising muramidase is administered to livestock in the growth phase of livestock production. 62. The method of any of the embodiments 31 to 58, wherein the ruminant feed composition comprising muramidase is administered to cattle at the stage of finishing the production of cattle. 63. The method of any of the modalities 31 to 58, wherein the feed composition for ruminants that i nnann / nznz / E / YiAi 176 comprising muramidase is administered to a calf. EXAMPLES Muramidases were cloned, expressed, characterized and their muramidase activity assessed as described in WO 2013 / 076253. Example 1 - Effect of muramidase on the production of rumen fermentation gas and the digestibility of the dry matter of the feed Materials and methods: The in vitro fermentation model was adapted from Menke Y Steingass, (Menke KH, Steingass H. (Estimation of the energetic feed value obtained from Chemical analysis and in vitro gas production using rumen fluid. Anim Res Dev. (1988) 28:7 -55).The experimental design included negative control treatments (NC, only feed and rumen buffer), positive control (PC, feed and rumen buffer added to a commercial rumen modifier (Monensin)), muramidase (SEQ. ID NO : 3, 6, 9, 12, 15, 18, 21, 24 and 27, muramidase negative control) and blanks (rumen buffer only), Table 1. The assay was repeated 2 times (assay 1 and assay 2) to increase the power of the overall study. i nnann / nznz / E / YiAi i nnann / nznz / E / YiAi Table 1 Treatment N Feed g Enzymatic class Dose mg of EP / kg feed Trial 1 Trial 2 Blank 3 3 — NC 4 6 0.5 PC (Monensin) 3 4 0.5 Non-enzymatic product 22 SEC. ID NO: 3 3 3 0.5 new MUR polypeptides having muramidase activity 50 SEC. ID NO: 6 3 3 0.5 new MUR polypeptides having muramidase activity 50 178 SEQ. ID NO: 9 3 3 0.5 new MUR polypeptides having muramidase activity 50 SEC. ID NO: 12 3 3 0.5 GH2 5 50 SEC. ID NO: 15 3 3 0.5 GH2 5 50 SEC. ID NO: 18 3 3 0.5 GH2 5 50 SEC. ID NO: 21 3 3 0.5 GH2 4 25 SEC. ID NO: 24 3 3 0.5 GH2 4 25 SEC. ID NO: 27 3 3 0.5 new MUR polypeptides having muramidase activity 50 The method was based on the incubation of ruminant feed in a buffer and ruminal fluid solution i nnann / nznz / E / YiAi 179 during a period of 48 h, while obtaining the cumulative gas production and the digestibility of the DM of the feed. The used mineral buffer solution was prepared according to Menke and Steingass (1988), and heated in a 39°C water bath and continuously purged with CO2 for 60 minutes. Sodium sulfite was used as a reducing agent in the buffer solution (0.33 g / 1 of solution). Rumen fluid was collected from 2 Jersey heifers (housed at the University of Copenhagen Experimental Farm, Denmark). Rumen fluid was collected through the rumen cannula and poured into two thermal flasks preheated to 39.010.5 °C and immediately transferred to the laboratory. The rumen fluid was filtered through 3 layers of cheesecloth to remove feed particles and mixed with mineral buffer at a ratio of 1 to 2 (Menke and Steingass, 1988). Rumen fluid and buffer solution were dispensed into a 90 ml Duran flask with a lid equipped with a wireless pressure transducer and gas valve (Ankom RF Gas Production System, Ankom Technology®, Macedon, NY, USA). After filling with 0.500010.0010 g of feed sample (corn silage, soybean meal at a 2:1 ratio based on dry matter) and preheated overnight at 39 °C. Duram flasks were dosed with 1.00 ml of treatment solution (or water or solution of 180 muramidase or positive control solution) and mixed before closing the flasks. All enzyme solutions (A to I) were produced by Novozymes and administered according to mg of enzyme protein per kg of feed. Table 1. Monensin (monensin sodium salt hydrate, lot no. BCBR9717V, Sigma-Aldrich, Buchs Switzerland) was used as PC at the concentration of 22 mg / kg feed, Table 1. All procedures were carried out with continuous purge with CO2. The headspace of each flask after filling was 41 ml. Fermentation gas was automatically released from the flasks through the gas valve whenever the pressure increased 0.75 PSI. The pressure difference related to the opening of the gas valve was used to calculate the cumulative gas production (ΔΡ) using the ideal gas law: GP = (ΔΡ / Ρο) ' Vo (1) where: ΔΡ is the cumulative pressure change (kPa) in the free space of the flask; Vo is the free volume of the flask (41 mi), Po is the atmospheric pressure. Gas production data was expressed as ml / g of DM incubated at normal pressure and was not included in the present example, but was used to ensure sufficient fermentation activity. Dry matter after fermentation was measured and related to dry matter in the flasks to determine dry matter digestibility ((dry matter before - dry matter after) / dry matter before). Data were expressed as the relative improvement of the 181 DMd compared to control when bottom fermentation of blanks is taken into account. Data were statistically analyzed using the ANOVA procedure included in JMP 12.1.0 (SAS Institute Inc.) and presented as LS means; the initial model included treatment, trial, and interactions and after model evaluation was reduced to the main effect of treatment. Results The results of the DMd are presented in figure 1 and show that the addition of muramidase increases the in vivo rumen digestion at 48h of the dry matter of the feed compared to the positive control (monensin). The data also show that the addition of some muramidases can increase the DMd of the ruminant feed compared to NC. conclusions In conclusion, in the two replicates of the same study, a series of muramidases from 3 different classes showed an improvement in rumen dry matter digestibility compared to the normally used rumen additive, monensin. The data also showed that most of the muramidases improve the digestibility of rumen dry matter compared to NC. Example 2 - Dose response effect of 5 muramidases on rumen fermentation and digestibility of i nnann / nznz / E / YiAi 182 the dry matter of the feed Summary: In vitro rumen fermentation using rumen fluid and buffer showed that muramidase can increase dry matter digestibility and increase rumen production of total acetate, propionate and VFA and increase the amount of total carbon in rumen VFA. Materials and methods: The assay was carried out by Alimetrics (Alimetrics Ltd, Koskelontie 19B, FIN-02920 Espoo, Finland) using 120 ml serum bottles as fermentation vessels. The preparation and the fermentation procedure are presented in Kettunen et al., (Kettunen H., J. Vuorenmaa, D. Gaffney and J. Apajalahti (2016): Yeast hydrolysate product enhances rumen fermentation in vitro. J. App. Anim. Nutr., Vol. 4; el; page 1 of 7). In summary, the method is as follows: All the bottles were initially filled with lg of DM of feed consisting of corn silage, barley meal, soybean meal, in amounts of 0.5, 0.4 and 0.1 g of DM. , respectively. Subsequently, the bottles were purged with CO2 passed through a hot copper O2 scavenging catalyst and sealed with a thick butyl rubber stopper. Temperature-adjusted (+38°C) reduced, anaerobic artificial saliva buffer was introduced (modified from i nnann / nznz / E / YiAi 183 Agriculture Handbook No. 379, (USDA, Washington, D.C., 1975), 37.65 ml volume), freshly strained rumen fluid (5% inoculum; 2 ml volume) and test compounds (0.35 ml volume) into the vessels fermentation with a flow of CO2 free of oxygen. After collection of rumen fluid from a ruminally cannulated cow. Rumen fluid was pumped directly from the rumen into a preheated flask, immediately closed, and transported to the Alimetrics laboratory. Rumen fluid was used for inoculation within 2 hours of collection. To guarantee the presence of ruminal microbes associated with both liquids and particles in the inoculum, both fractions were obtained. The liquid and solid fractions were strained through a metal mesh (3 x 3 mm mesh size) under anaerobic conditions prior to buffer dilution. After inoculation with rumen fluid, buffer and test solution, the containers were sealed with butyl rubber septa. All fermentation vessels were inoculated in random order to prevent possible blocking effects. The inoculation time for each fermentation vessel was recorded and accounted for on each sample to ensure that the fermentation was the same for each sample. The fermentation was continued for 12h on a rotary shaker at +38°C. sennann / nznz / E / YiAi 184 measured the fermentation gas produced and relieved it by collecting the fermentation gas in syringes at 3, 6, 9 and 12h. Feed residues were measured after 12h of fermentation. The trial design was a completely randomized dose-response design with 28 treatments using 150 fermentation vessels according to Table 2. The 25 muramidase solutions were diluted to the required concentration in enzyme buffer (BSA, Tween 20, acetate buffer, calcium, NaOH, adjusted to pH 6). The negative control was supplemented with the same buffer that was used to dilute the enzymes to the same volume of liquid as the supplemented fermentation vessels. The ionophore monensin (monensin sodium salt, 90-95% TLC (Sigma Aldrich; Product Code: M5273-1G)) was selected as a positive control because it is a ruminant feed additive that affects fatty acid production. volatile (VEA). i nnann / nznz / E / YiAi Table 2: treatments, doses and study design Dose N / dose SEC. ID Enzymatic class 1 2 3 4 5 mg / 40 ml NC 15 PC (Monensin) 5 Non-enzymatic product 0.05 0.25 185 A 5 SEC. ID NO: 28 GH24 0.05 0.1 0.2 0.4 0.8 B 5 SEC. ID NO: 21 GH24 0.05 0.1 0.2 0.4 0.8 C 5 SEC. ID NO: 12 GH25 0.05 0.1 0.2 0.4 0.8 D 5 SEC. ID NO: 18 GH25 0.05 0.1 0.2 0.4 0.8 E 5 THX3038 SEC. ID NO: 9 new MUR polypeptides having muramidase activity 0.05 0.1 0.2 0.4 0.8 i nnann / nznz / E / YiAi Sample collection Liquid samples obtained at 12h were analyzed for VEA (acetate, propionate, butyrate and valerate) concentration by GC-FID using a glass column packed with 80 / 120 carbopack B-DA / Carbowax stationary phase at 4% and helium as carrier gas (Kettunen H., J. Vuorenmaa, T. Rinttila, H. Grbnberg, E. Valkonen and J. Apajalahti (2015): Natural resin acid-enriched composition as a modulator of intestinal microbiota and performance enhancer in broiler chicken. J. App. Anim. Nutr., Vol. 3; e2; page 1 of 9). The digestibility of dry matter was quantified 186 by determination of the dry matter in the original feed matrix and in all fermentation vessels after 12h of fermentation. Feed residues from the fermentation vessels were obtained by filtration on tared sintered glass filters, washed with water and dried at 105°C for 12 hours. Finally, the glass filters are weighed to determine the dry matter of the residual feed. calculations and statistics Dry matter digestibility was calculated as the ratio between feed residues after finishing fermentation and initial dry matter. The sum of the VFAs was calculated as the sum of acetate, propionate, butyrate and valerate and the summed carbon in the VFAs was calculated by assigning the respective number of carbon atoms in the acetate, propionate, butyrate and valerate, 2, 3, 4 and 5, respectively. Relative improvement compared to NC was calculated for DMd and concentration of acetate, propionate, butyrate, total VFAs, and total carbon in VFAs. Data were analyzed for linear and quadratic effects using the linear regression algorithm included in the mixed procedure of SAS (SAS institute). Data presented are linear regression estimates and standard error, as well as least-squares means and standard error, unless otherwise stated. 187 Results : Data demonstrate that muramidases can affect rumen dry matter digestibility and VFA production in vitro, Figures 2-7. All muramidase treatments increased DMd when compared to control. The greatest improvement was for treatment C (9.5%), when the fermentation was supplemented with 0.8 mg / 40 ml. All muramidase treatments numerically increased ruminal acetate and propionate production compared to control. Acetate increased by 16.0% when treatment A was supplemented at 0.4 mg / 40 ml; at the same dose, propionate increased by 24%, resulting in an 11% increase in total VFA production, Figures 3 and 4, respectively. Treatment A and B also reduced rumen butyrate production compared to control, Figure 5. However, carbon in VFA was still positively affected despite the reduction in butyrate; the improvement in relation to the NC was up to 7.3%, figure 7. Linear regression analysis identified treatments A, B, and C as the most potent for increasing ruminal acetate and propionate production. Linear regression analysis also identified treatments A, B, and C as the most potent in reducing rumen production of i nnann / nznz / E / YiAi. 188 butyrate. The effect on acetate and propionate according to the dose of treatment A, B and C was quadratic. Total rumen VEA production and total carbon in rumen VEAs were affected in a quadratic manner by the muramidase dose for treatment C. Conclusion: In conclusion, the data demonstrate that muramidase can increase dry matter digestibility and increase rumen production of total acetate, propionate and VEA and increase the amount of total carbon in rumen VEA in vitro. Example 3 - Effect of 13 muramidases on ruminal fermentation and digestibility of dry matter of feed in vitro Summary: A fermentation study was carried out using 13 muramidases from the GH24, GH25 families of glycoside hydrolases (GH) and novel MUR polypeptides having muramidase activity; the number of enzymes evaluated was 5, 4 and 4, respectively. Fermentation was carried out in vitro using rumen fluid and artificial saliva solution in 120 ml fermenters. The hypothesis was that muramidases can increase the production of rumen fermentation products. In conclusion, the data demonstrate that muramidases i nnann / nznz / E / YiAi 189 of the families of glycoside hydrolases (GH) GH24, GH25 and the novel MUR polypeptides that have muramidase activity can affect rumen dry matter digestibility and rumen fermentation by increasing production of propionate, total volatile fatty acids and carbon total in volatile fatty acids. Materials and methods: The assay was carried out by Alimetrics (Alimetrics Ltd, Koskelontie 19B, FIN-02920 Espoo, Finland) using 120 ml serum bottles as fermentation vessels. The preparation and the fermentation procedure are presented in Kettunen et al., (Kettunen H., J. Vuorenmaa, D. Gaffney and J. Apajalahti (2016): Yeast hydrolysate product enhances rumen fermentation in vitro. J. App. Anim. Nutr., Vol. 4; the; page 1 of 7). In summary, the method is as follows: All the bottles were initially filled with Ig of DM of feed made up of corn silage, barley meal, soybean meal, in amounts of 0.5, 0.4 and 0.1 g of DM. , respectively. Subsequently, the bottles were purged with CO2 passed through a hot copper O2 scavenging catalyst and sealed with a thick butyl rubber stopper. Temperature-adjusted (+38°C) reduced, anaerobic artificial saliva buffer was introduced (modified from Agriculture Handbook No. 379, (USDA, Washington, D.C., 1975), nnann / nznz / E / YiAi 190 37.65 ml volume), freshly strained rumen fluid (5% inoculum; 2 ml volume) and test compounds (0.35 ml volume) in the fermentation vessels with a flow of oxygen-free CO2. After collection of rumen fluid from a ruminally cannulated cow. Rumen fluid was pumped directly from the rumen into a preheated flask, immediately closed, and transported to the Alimetrics laboratory. Rumen fluid was used for inoculation within 2 hours of collection. To guarantee the presence of ruminal microbes associated with both liquids and particles in the inoculum, both fractions were obtained. The liquid and solid fractions were strained through a metal mesh (3 x 3 mm mesh size) under anaerobic conditions prior to buffer dilution. After inoculation with rumen fluid, buffer and test solution, the containers were sealed with butyl rubber septa. All fermentation vessels were inoculated in random order to prevent possible blocking effects. The inoculation time for each fermentation vessel was recorded and accounted for on each sample to ensure that the fermentation was the same for each sample. The fermentation was continued for 12h on a rotary shaker at +38°C. Produced fermentation gas was measured and relieved by collecting nnann / nznz / E / YiAi 191 the fermentation gas in syringes at 3, 6, 9 and 12 o'clock. Feed residues were measured after 12h of fermentation. The trial design was a completely randomized dose-response design with 28 treatments using 150 fermentation vessels according to Table 3. The 13 muramidase solutions were diluted to the required concentration in enzyme buffer (BSA, Tween 20, acetate buffer, calcium, NaOH, adjusted to pH 6). The negative control was supplemented with the same buffer that was used to dilute the enzymes to the same volume of liquid as the supplemented fermentation vessels. The ionophore monensin (monensin sodium salt, 90-95% TLC (Sigma Aldrich; Product Code: M5273-1G)) was selected as a positive control because it is a ruminant feed additive that affects fatty acid production. volatile (VEA). i nnann / nznz / E / YiAi Table 3: treatments, doses and study design Dose N / dose SEC. ID Enzymatic class 1 2 3 4 5 mg / 40 mi NC 15 PC (Monensin) 5 Non-enzymatic product 0.01 0.1 A 5 / 25 SEC. ID NO: 28 GH24 0.025 0.05 0.1 0.2 0.4 B 5 / 25 SEC. ID NO: GH24 0.025 0.05 0.1 0.2 0.4 192 21c5 / 25 SEC. ID NO: 12 GH25 0.025 0.05 0.1 0.2 0.4 D 5 SEC. ID NO: 29 GH24 0.2 E 5 SEC. ID NO: 30 GH24 0.2 F 5 SEC. ID NO: 31 GH24 0.2 G 5 SEC. ID NO: 32 GH25 0.2 H 5 SEC. ID NO: 33 GH25 0.2 1 5 SEC. ID NO: 34 GH25 0.2 J 5 SEC. ID NO: 35 new MUR polypeptides having muramidase activity 0.2 K 5 SEC. ID NO: 36 new MUR polypeptides having muramidase activity 0.2 L 5 SEC. ID NO: 36 new MUR polypeptides having 0.2 M muramidase activity 5 SEQ. ID NO: 37 novel MUR polypeptides having 0.2 muramidase activity Sample collection Fluid samples obtained at 12h were analyzed for VFA (acetate, propionate, butyrate and valerate) concentration by GC-FID using an i nnann / nznz / E / YiAi 193 glass column packed with 80 / 120 carbopack B-DA / Carbowax 4% stationary phase and helium as carrier gas (Kettunen H., J. Vuorenmaa, T. Rinttilá, H. Grbnberg, E. Valkonen and J. Apajalahti (2015) : Natural resin acid-enriched composition as a modulator of intestinal microbiota and performance enhancer in broiler chicken. J. App. Anim. Nutr., Vol. 3; e2; page 1 of 9) . Dry matter digestibility was quantified by determining dry matter in the original feed matrix and in all fermentation vessels after 12h of fermentation. Feed residues from the fermentation vessels were obtained by filtration on tared sintered glass filters, washed with water and dried at 105°C for 12 hours. Finally, the glass filters are weighed to determine the dry matter of the residual feed. calculations and statistics Dry matter digestibility (DMd) was calculated as the ratio between feed residues after the end of fermentation and the initial dry matter. The sum of the VFAs was calculated as the sum of acetate, propionate, butyrate, and valerate, and the summed carbon in the VFAs was calculated by assigning the respective number of carbon atoms in the acetate, propionate, butyrate, and valerate, 2, 3, 4 and 5, respectively. The data was calculated as the 194 relative improvement compared to the NC for the digestibility of the DM and the concentration of acetate, propionate, butyrate, added VFA and total carbon in the VFA. The data was divided into two data sets. Data set one included data from the NC treatment and all muramidase 0.20 mg / 40 mL and PC 0.01 mg / 40 mL treatments, for analysis using the mixed SAS procedure (Institute SAS) and treatment as the main effect. Data set two included data from treatments A, B, and C for all 5 doses, to analyze linear and quadratic effects using the algorithm for linear regression included in the SAS Mixed Procedure (SAS Institute). Data presented are linear regression estimates and standard error, as well as least-squares means and standard error, unless otherwise stated. Results: Data from the present study demonstrate that muramidases can affect rumen dDM and VFA production in vitro, Table 4 and Figures 8-10. The difference in DMd between the non-supplemented NC and muramidase treatments were positive for 10 of 13 muramidases, when tested at the same dose (0.2 mg / 40 ml). The maximum improvement in DMd is 8.6%, Figure 8. The increasing response in DMd was evenly distributed across the 3 195 glycoside hydrolase (GH) families (GH24, GH25, and novel MUR polypeptides having muramidase activity defined herein, with 5 / 5, 2 / 4, and 3 / 4, respectively. The data also show a clear effect of muramidase supplementation on propionate production Propionate production was increased compared to NC for 9 of 13 muramidases when tested at the same dose (0.2 mg / 40 mL) The increase in propionate production was up to 14.4%, Figure 9. The increased response in propionate production was divided into the families of glycoside hydrolase (GH) GH24, GH25, and novel MUR polypeptides that have muramidase activity, in that order (5 / 5, 3 / 4 and 1 / 4, respectively) Muramidase treatments reduced butyrate production compared to control for 9 of 13 muramidases, when tested at the same dose (0.2 mg / 40 mL). was up to 49.3%, Figure 10. The decreased response in butyrate production was divided into the families of glycoside hydrolase (GH) GH24, GH25 and the new MUR polypeptides that have muramidase activity (4 / 5, 2 / 4 and 3 / 4, respectively) . The effect of supplementing 0.2 mg muramidase / 40 ml increased overall VEA production and total carbon in VEAs for 8 of 13 treatments, when compared to control, Table 4. Increased 196 Total VFAs and total carbon in VFAs were divided into the glycoside hydrolase (GH) families GH24, GH25, and the novel MUR polypeptides that have muramidase activity, in that order (4 / 5, 2 / 4, and 2 / 4, respectively). For the three muramidases A, B and C, a regression analysis was carried out. Regression analysis showed that propionate production increased with increasing muramidase dose and butyrate production decreased with increasing muramidase dose, also seen in Figures 9 and 10, respectively. Table 4: Effect of 13 muramidases (0.2 mg / 40 ml dose) on dry matter digestibility and VFA production (mmol / 1) after 12 h of ruminal fermentation in i nnann / nznz / E / YiAi vi three DMd Acetate Propionate Butyrate Total VFAs Carbon in VFAs NC 0.57 48.5 41.2 6.62 97 250 A 0.59 49.8 47.2 3.35 101 256 B 0.58 49.5 45.2 4.27 99 254 C 0.58 48.8 4 2.4 6.3 98 252 D 0.61 48.1 42.2 6.27 97 250 E 0.58 48.7 42.9 6.52 99 255 F 0.57 49.3 43.2 6.93 100 258 197 G 0.56 48.6 42.3 5.70 97 249 H 0.59 51.8 45.1 7.19 105 270 1 0.56 47.1 40 6.62 94 243 J 0.6 47.9 41.2 6.38 96 247 K 0.58 49.3 42.2 6.79 99 255 L 0.58 46.1 38.8 6.21 92 236 M 0.56 48.3 40 6.48 95 245 PC 0.55 47.5 46.4 3.86 98 251 EEM 0.016 1.38 1.47 0.21 3 7.8 i nnann / nznz / E / YiAi Conclusion: In conclusion, the data demonstrate that muramidases from the glycoside hydrolase (GH) families GH24, GH25 and novel MUR polypeptides having muramidase activity can affect rumen dry matter digestibility and rumen fermentation by increasing propionate production. , total VFAs and the total carbon in the VFAs. Example 4 - Effect of 22 muramidases on rumen fermentation and digestibility of dry matter of feed in vitro Summary: A fermentation study was carried out using muramidases from the GH24, GH25 families of glycoside hydrolases (GH) and novel MUR polypeptides having muramidase activity; the number of enzymes evaluated was 9, 8 and 7, 198 respectively. Fermentation was carried out in vitro using rumen fluid and artificial saliva solution in 120 ml fermentors. The hypothesis was that muramidases can increase the production of rumen fermentation products. In conclusion, rumen fermentation was improved by supplementing with muramidases from the three families of glycoside hydrolase (GH) GH24, GH25 and novel MUR polypeptides having muramidase activity. The improvement was observed as increased production of total volatile fatty acids, acetate and propionate. Materials and methods: The assay was carried out by Alimetrics (Alimetrics Ltd, Koskelontie 19B, FIN-02920 Espoo, Finland) using 120 ml serum bottles as fermentation vessels. The preparation and the fermentation procedure are presented in Kettunen et al., (Kettunen H., J. Vuorenmaa, D. Gaffney and J. Apajalahti (2016): Yeast hydrolysate product enhances rumen fermentation in vitro. J. App. Anim. Nutr., Vol. 4; the; page 1 of 7). In summary, the method is as follows: All the bottles were initially filled with Ig of DM of feed made up of corn silage, barley meal, soybean meal, in amounts of 0.5, 0.4 and 0.1 g of DM. , respectively. Subsequently, the bottles were purged with CO2 passed through an nnann / nznz / E / YiAi 199 hot copper catalyst for O2 scrubbing and sealed with a thick butyl rubber plug. Reduced, temperature-adjusted (+38°C) anaerobic artificial saliva buffer solution (modified from Agriculture Handbook No. 379, (USDA, Washington, D.C., 1975), volume 37.65 ml), freshly strained ruminal fluid ( 5% inoculum; 2 ml volume) and test compounds (0.35 ml volume) into the fermentation vessels with a flow of oxygen-free CO2. Next, rumen fluid was collected from a rumenally cannulated cow. Rumen fluid was pumped directly from the rumen into a preheated flask, immediately closed, and transported to the Alimetrics laboratory. Rumen fluid was used for inoculation within 2 hours of collection. To guarantee the presence of ruminal microbes associated with both liquids and particles in the inoculum, both fractions were obtained. The liquid and solid fractions were strained through a metal mesh (3 x 3 mm mesh size) under anaerobic conditions prior to buffer dilution. After inoculation with rumen fluid, buffer and test solution, the containers were sealed with butyl rubber septa. All fermentation vessels were inoculated in random order to prevent possible blocking effects. was recorded on 200 inoculation time for each fermentation vessel and was taken into account in each sample to ensure that the fermentation was the same for each sample. The fermentation was continued for 12h on a rotary shaker at +38°C. The fermentation gas produced was measured and relieved by collecting the fermentation gas in syringes at 3, 6, 9 and 12h. Feed residues were measured after 12h of fermentation. The trial design was a completely randomized dose-response design with 27 treatments using 145 fermentation vessels according to Table 5. The 24 muramidase solutions were diluted to the required concentration in enzyme buffer (BSA, Tween 20, acetate buffer, calcium, NaOH, adjusted to pH 6). The negative control was supplemented with the same buffer that was used to dilute the enzymes to the same volume of liquid as the supplemented fermentation vessels. The ionophore monensin (monensin sodium salt, 90-95% TLC (Sigma Aldrich; Product Code: M5273-1G)) was selected as a positive control because it is a ruminant feed additive that affects fatty acid production. volatile (VEA). i nnann / nznz / E / YiAi Table 5: Treatments, doses and study design i nnann / nznz / E / YiAi Dose N / dose SEC. ID Enzymatic class 1 2 mg / 40 mi NC 15 PC (Monensin) 5 Non-enzymatic product 0.01 0.10 A 5 SEC. ID NO: 38 GH24 0.20 B 5 SEC. ID NO: 39 GH24 0.20 C 5 SEC. ID NO: 40 GH24 0.20 D 5 SEC. ID NO: 41 GH24 0.20 E 5 SEC. ID NO: 42 GH24 0.20 F 5 SEC. ID NO: 43 GH24 0.20 G 5 SEC. ID NO: 44 GH24 0.20 H 5 SEC. ID NO: 45 GH24 0.20 1 5 SEC. ID NO: 46 GH24 0.20 J 5 SEC. ID NO: 47 GH25 0.20K 5 SEC. ID NO: 48 GH25 0.20 L 5 SEC. ID NO: 49 GH25 0.20 M 5 SEC. ID NO: 50 GH25 0.20 N 5 SEC. ID NO: 51 GH25 0.20 0 5 SEC. ID NO: 52 GH25 0.20 S 5 SEC. ID NO: 55 new MUR polypeptides having muramidase activity 0.20 T 5 SEC. ID NO: 56 new MUR polypeptides having muramidase activity 0.20 U 5 SEC. ID NO: 57 new MUR polypeptides having muramidase activity 0.20 V 5 SEC. ID NO: 58 new MUR polypeptides having muramidase activity 0.20 w 5 SEC. ID NO: 59 new MUR polypeptides having muramidase activity 0.20 Y 5 SEC. ID NO: 53 new MUR polypeptides having muramidase activity 0.20 z 5 SEC. ID NO: 54 new MUR polypeptides having muramidase activity 0.20 i nnann / nznz / E / YiAi Sample collection Liquid samples obtained at 12h were analyzed for VFA (acetate, propionate, butyrate and valerate) concentration by GC-FID using a glass column packed with 80 / 120 stationary phase carbopack B-DA / Carbowax at 4% and helium as carrier gas (Kettunen H., J. Vuorenmaa, T. Rinttila, H. Grónberg, E. Valkonen and J. Apajalahti (2015): Natural resin acid-enriched composition as a modulator of intestinal microbiota and performance enhancer in broiler chicken. J. App. Anim. Nutr., Vol. 3; e2; page 1 of 9) . Dry matter digestibility was quantified by determining dry matter in the original feed matrix and in all fermentation vessels after 12h of fermentation. The feed residues of the 203 fermentation vessels were obtained by filtration on tared sintered glass filters, washed with water and dried at 105°C for 12 hours. Finally, the glass filters are weighed to determine the dry matter of the residual feed. calculations and statistics Dry matter digestibility (DMd) was calculated as the ratio between feed residues after the end of fermentation and the initial dry matter. The sum of the VFAs was calculated as the sum of acetate, propionate, butyrate, and valerate, and the summed carbon in the VFAs was calculated by assigning the respective number of carbon atoms in the acetate, propionate, butyrate, 2, 3, 4, and 5. , respectively. Data were calculated as the relative improvement compared to NC for DMd and the concentration of acetate, propionate, summed VFA and total carbon in VFA. One treatment was removed from the data set, because the amount of enzyme used was not known. Therefore, the data from this treatment cannot be compared with the other treatments in the present study. Data were analyzed using the mixed SAS procedure (SAS institute) including the main effect of treatment. Data presented are means of minima i nnann / nznz / E / YiAi 204 squares and the standard error, unless otherwise stated. Results: The data demonstrate that ruminal fermentation was improved by muramidase supplementation in vitro. This was demonstrated from the increase in total rumen VFAs and total carbon in VFAs for 23 of 24 muramidase treatments, Table 6. The positive response was evenly split across the three families of glycoside hydrolase (GH) enzymes (GH24 , GH25 and novel MUR polypeptides having muramidase activity). The total VFAs increased up to 12,211.99% and the total carbon in the VFAs increased up to 12,512.02%, figures 13 and 14, respectively. The total increase in VFA and total carbon in VFA arose from an increase in rumen acetate and propionate, Table 6. Acetate fermentation increased up to 10,711.99% and propionate fermentation increased up to 14,212.21 %, figures 13 and 14, respectively. i nnann / nznz / E / YiAi 205 Table 6: Effect of 24 muramidases on dry matter digestibility (DMd) and production of volatile fatty acids (VFA) (mmol / 1) after 12 h of in vibro rumen fermentation Item DMd Acetate Propionate Butyrate Total VFAs Carbon in VFAs NC 0.58 48.4 39.5 7.1 96 246 PC 0.51 44.2 42.8 3.7 91 234 A 0.56 52.9 45.1 6.7 105 271 B 0.60 49.1 40. 4 7.2 97 251 C 0.58 52.0 44.3 7.2 104 269 D 0.57 50.1 43.0 5.9 99 255 E 0.57 49.9 42.3 6.2 99 254 F 0.58 51.6 42.5 7.2 102 263 G 0.56 49.7 41.1 7.3 99 255 H 0.59 52.6 44.7 5.3 103 264 1 0.56 49.3 42.9 5.4 98 252 J 0.56 47.6 39.1 6.9 94 243 K 0.57 49.5 40.9 7.2 98 254 L 0.56 50.7 42.0 7.3 101 259 M 0.60 50.7 42.0 7.3 101 259 N 0.59 49.3 40.8 7.2 98 253 0 0.59 51.1 42.0 7.3 101 260 S 0 .58 49.4 41.2 7.1 98 254 T 0.57 53.6 45.1 7.8 107 277 U 0.60 49.1 40.5 7.1 97 251 V 0.59 49.2 40.6 7.1 97 252 W 0.59 48.9 40.9 6.7 97 250 Y 0.57 50.8 43.1 6.1 100 258 Z 0.56 48.7 39.6 6.9 96 247 SEM 0.02 0 .96 0.87 0.29 1.90 4.96 206 Conclusion: In conclusion, rumen fermentation was improved by supplementing with muramidases from the three families of glycoside hydrolase (GH) GH24, GH25 and novel MUR polypeptides having muramidase activity. The improvement was observed as increased production of total volatile fatty acids, acetate and propionate. It is noted that as of this date, the best method known to the applicant for putting said invention into practice is the one that is clear from the present description of the invention.

Claims

Having described the invention as above, the following claims are claimed as property:

1. A ruminant feed composition, such as a ruminant feed, ruminant feed supplement or ruminant feed additive, characterized in that it comprises one or more muramidases, wherein the muramidase is present in a sufficient quantity for administration at a level of 1 to 200 mg of enzyme protein per kg of ruminant feed.

2. The ruminant feed composition according to claim 1, characterized in that the ruminant is selected from the group consisting of: cattle, dairy cattle and livestock.

3. The ruminant feed composition according to any of claims 1 to 2, characterized in that the muramidase comprises one or more domains of a glycoside hydrolase (GH) family selected from the list consisting of GH24, GH25 and novel MUR polypeptides having muramidase activity.

4. A method for improving the energy-corrected milk production (ECM) of a ruminant, characterized in that it comprises administering to the ruminant a composition of 208 ruminant feed in accordance with any of claims 1 to 3.

5. A method for increasing the dry matter digestibility (DMd) of a ruminant feed, ruminant feed supplement, or ruminant feed additive, characterized in that it comprises the steps of: a) providing at least one muramidase; b) providing a ruminant feed, ruminant feed supplement, or ruminant feed additive suitable for a ruminant animal; c) applying the muramidase to the ruminant feed, ruminant feed supplement, or ruminant feed additive to form a ruminant feed composition; and d) feeding the ruminant feed composition to the ruminant animal, whereby an increase in dry matter digestibility is effected.

6. The method according to claim 5, characterized in that the production of volatile fatty acids (VFA) in the rumen increases compared to the production of VFA in the rumen of a ruminant that is not fed a muramidase.

7. The method according to any of claims 5 to 6, characterized in that the production of propionate in the rumen increases compared to the propionate production in the rumen of a ruminant that is not fed a muramidase. 209 8. The method according to any of claims 5 to 7, characterized in that the production of acetate in the rumen increases compared to the production of acetate in the rumen of a ruminant that is not fed a muramidase.

9. The method according to any of claims 5 to 8, characterized in that the muramidase is administered at a level of 1 to 200 mg of enzyme protein per kg of dry matter of ruminant feed.

10. The method according to any of claims 5 to 9, characterized in that the energy-corrected milk production (ECM) of ruminants after administration improves by at least 1.0%, preferably at least 1.5%, more preferably at least 2.0% compared to the control.

11. The method according to any of claims 5 to 10, characterized in that the muramidase is of microbial origin.

12. The method according to any of claims 5 to 11, characterized in that the muramidase comprises one or more domains of a glycoside hydrolase (GH) family selected from the list consisting of GH24, GH25 and novel MUR polypeptides having muramidase activity.

13. The method in accordance with any of claims 5 to 12, characterized in that the control is a ruminant feed composition not comprising muramidase.

14. The method according to any of claims 5 to 12, characterized in that the control is a ruminant feed composition not comprising muramidase GH24, muramidase GH25 or novel MUR polypeptides having muramidase activity.

15. The method in accordance with any of claims 5 to 14, characterized in that the control is monensin.