Composite boar feed additive and preparation process thereof

Abstract

The invention belongs to the technical field of livestock feed, and discloses a composite boar feed additive and a preparation process thereof. The additive is prepared from tea polyphenol, rosmarinic acid, quercetin, enteric sodium butyrate, yeast cell wall polysaccharide, embedded bacillus subtilis metabolite and a modified starch carrier, the activity of urease and deaminase of posterior intestinal ammonia-producing bacteria is inhibited through multi-component synergism, and nitrogen is regulated and controlled to be converted into mycoprotein. The preparation process comprises the following steps: dissolving and attaching active ingredients, coating enteric-coated pellets, embedding double-layer microcapsules and performing multi-stage mixing. According to the invention, enzyme inhibition functions of tea polyphenol, rosmarinic acid and quercetin are integrated with intestinal barrier strengthening and pH regulation of sodium butyrate, flora regulation of yeast cell wall polysaccharide and targeted bacteriostasis functions of embedded bacillus subtilis metabolites, and accurate release in specific sections of intestinal tracts is realized through enteric coating and microcapsule technologies; on the premise that the protein level of daily ration is not reduced and the reproductive performance is not damaged, the ammonia nitrogen emission is obviously reduced.

Description

Technical Field

[0001] This invention belongs to the field of livestock feed technology and relates to a compound boar feed additive and its preparation process. Background Technology

[0002] As the primary carrier of animal nutrition, feed formulation must not only meet the basic requirements for growth and reproductive performance but also consider the ecological effects of nitrogen metabolism. High-protein diets are widely used in the feeding of breeding boars to maintain semen quality and gonadal function through sufficient amino acid supply. After digestion and absorption, protein provides essential precursors for the body to synthesize protamine, enzymes, and hormones.

[0003] Boars generally have low apparent digestibility of crude protein in their diets. A large amount of protein not fully absorbed by the small intestine enters the hindgut, where it undergoes excessive fermentation under the catalysis of microbial ureases and deaminases, generating large amounts of ammonia, amines, and volatile fatty acids as metabolic byproducts. Ammonia nitrogen is not only excreted in large quantities into the environment in urine and feces, causing eutrophication of water bodies and atmospheric ammonia pollution, but it can also reflux into the bloodstream through enterohepatic circulation, inducing mild metabolic stress and indirectly interfering with testicular microenvironment homeostasis and spermatogenesis.

[0004] Current feed additives mostly focus on growth promotion or antibacterial functions, such as antibiotic substitutes, prebiotics, or single enzyme preparations. While these can improve overall digestibility to some extent, they fail to precisely intervene in the critical process of hindgut microbial-mediated protein degradation and ammonia production. Simply reducing dietary protein levels to decrease nitrogen emissions can easily lead to insufficient intake of essential amino acids, thereby impairing semen quality and libido, creating a structural contradiction between emission reduction and reproductive health. Summary of the Invention

[0005] To achieve the above-mentioned objectives, this invention provides a compound boar feed additive and its preparation process. The compound boar feed additive, through the synergistic effect of a specific ratio of natural plant-derived active components and microbial metabolic regulatory factors, selectively inhibits the urease and deaminase activities of ammonia-producing bacteria in the hindgut microenvironment of boars, while promoting the directional conversion of nitrogen into bacterial proteins. Thus, while maintaining the semen quality and libido of breeding boars, it significantly reduces the amount of ammonia nitrogen emitted in feces and urine.

[0006] The compound boar feed additive of this invention is composed of the following components in parts by weight: 15-25 parts tea polyphenols, 8-12 parts rosmarinic acid, 5-9 parts quercetin, 10-18 parts sodium butyrate, 12-20 parts yeast cell wall polysaccharide, 6-10 parts encapsulated Bacillus subtilis metabolite, and 30-50 parts carrier; wherein, the encapsulated Bacillus subtilis metabolite is prepared by ultrafiltration concentration of Bacillus subtilis fermentation broth and encapsulation using sodium alginate-chitosan double-layer microcapsule technology, and its core active ingredient is a cyclic lipopeptide substance with a molecular weight between 800-1500 Da. This substance is slowly released in the intestinal environment with a pH value greater than 6.5 and has a specific inhibitory effect on Clostridium ammoniagenicum and Bacteroides, but no inhibitory effect on Lactobacillus and Bifidobacterium.

[0007] The tea polyphenols have a gallate content higher than 70% and a total catechin content higher than 85% to ensure their strong chelating effect on urease activity; the ortho-dihydroxyl groups in the molecular structure of rosmarinic acid can effectively block the cofactor binding sites of deaminase; the quercetin exists in the form of amorphous nanoparticles with a particle size distribution of 80-120 nm, and is prepared by high-pressure homogenization and spray drying processes to improve its solubility and bioavailability in the alkaline environment of the hindgut; the sodium butyrate is added in the form of enteric-coated microspheres, and its coating... The material is Eudragit L100 acrylic resin with a coating thickness of 35-45 μm, ensuring that it does not release in the front of the small intestine, but disintegrates and releases when the pH value rises above 6.8 in the terminal ileum to colon region; the yeast cell wall polysaccharide has a β-glucan content of more than 40% and a mannan oligosaccharide content of more than 30%, with a molecular weight distribution of 5000-20000 Da, which acts as a prebiotic to selectively promote the proliferation of short-chain fatty acid-producing bacteria, thereby reducing the local pH value of the hindgut and indirectly inhibiting the optimal activity environment of urease.

[0008] In a preferred embodiment of the present invention, the carrier is corn starch modified by surface hydroxypropylation, with a degree of substitution of 0.08-0.12 and a gelatinization temperature of 68-72°C, which maintains structural stability during feed pelleting and avoids the deactivation of active ingredients under high temperature and high humidity conditions.

[0009] The present invention also provides a preparation process for the above-mentioned compound boar feed additive, comprising the following steps: Step 1: Mix tea polyphenols, rosmarinic acid and quercetin according to the formula ratio, add anhydrous ethanol at a ratio of 3 times the total mass of the three, stir and dissolve at 40°C for 30 minutes to form a clear solution A; Step 2: Sodium butyrate and acrylic resin Eudragit L100 are mixed at a mass ratio of 4:1 and dissolved in 95% ethanol to prepare a coating solution with a solid content of 20%. The sodium butyrate particles are then bottom-sprayed in a fluidized bed with an inlet air temperature of 55°C and an atomization pressure of 1.8 Pa. After coating, the particles are vacuum dried at 45°C for 4 hours to obtain enteric-coated sodium butyrate microspheres. Step 3: Bacillus subtilis (preservation number CGMCC 1.102) was inoculated into a liquid culture medium containing 15 g / L soybean peptone, 5 g / L yeast extract, and 5 g / L sodium chloride. The medium was cultured at 37°C and 180 rpm for 24 h with shaking. After centrifugation to remove the bacterial cells, the supernatant was concentrated to 1 / 5 of its original volume through an ultrafiltration membrane with a molecular weight cutoff of 3000 Da, obtaining a concentrated solution rich in cyclic lipopeptides. This concentrated solution was mixed with 2% sodium alginate solution at a volume ratio of 1:2 and dripped into 0.1 mol / L calcium chloride solution through a 0.3 mm diameter stainless steel needle to form gel beads with a diameter of 0.8-1.2 mm. After standing and solidifying for 2 h, the beads were then immersed in 0.5% chitosan acetate solution (pH 4.8) to coat a second layer, solidified for 1 h, washed, and dried to obtain the embedded Bacillus subtilis metabolite. Step 4: Premix yeast cell wall polysaccharides and hydroxypropylated corn starch carrier in a V-type mixer for 10 minutes according to the formula ratio. Then add solution A obtained in step 1, remove ethanol by vacuum rotary evaporation at 45°C to make the active ingredients uniformly adhere to the carrier surface, and continue drying at 50°C until the moisture content is less than 8%. Step 5: The enteric-coated sodium butyrate microspheres obtained in Step 2, the embedded Bacillus subtilis metabolites obtained in Step 3, and the mixture obtained in Step 4 are mixed in a three-dimensional motion mixer at 15 rpm for 20 min to obtain the finished compound boar feed additive.

[0010] The method of using the compound boar feed additive of the present invention is as follows: mix it evenly with 1.5-2.5 kg per ton of complete compound feed, and feed it to adult boars weighing 80-120 kg twice a day. The amount of feed each time is adjusted to 2.2-2.8 kg according to the weight.

[0011] The technical principle of this invention lies in constructing a multi-level, spatiotemporally coordinated intestinal nitrogen metabolism regulation scheme.

[0012] First, tea polyphenols form a stable chelate with nickel ions at the active site of urease through their pyrogallol structure, which directly inhibits the reaction rate of urease catalyzing the hydrolysis of urea into ammonia. Secondly, rosmarinic acid competitively occupies the flavin adenine dinucleotide binding pocket of deaminase, thus blocking the metabolic pathway of amino acid deamination to produce α-keto acids and ammonia. Quercetin nanoparticles dissolve in the alkaline environment of the hindgut, and their flavonoid skeleton can insert into the phospholipid bilayer of the ammonia-producing bacteria cell membrane, increasing membrane permeability and causing an imbalance in the intracellular proton gradient, thereby inhibiting their growth and metabolic activity. Fourth, after being released in the colon, enteric sodium butyrate is absorbed by colonic epithelial cells and converted into butyryl coenzyme A. On the one hand, it serves as an energy substrate to enhance the intestinal barrier function and reduce the absorption of ammonia through the enterohepatic circulation. On the other hand, the unabsorbed portion lowers the local pH value, causing the environment to deviate from the optimal pH of urease (7.5-8.0), indirectly weakening the ammonia production efficiency. Fifth, mannan oligosaccharides in yeast cell wall polysaccharides act as receptor analogs, binding to fimbrial agglutinins on the surface of ammonia-producing bacteria, preventing them from adhering to the intestinal epithelium and promoting their excretion with feces, while β-glucan selectively stimulates the proliferation of butyric acid-producing bacteria, forming a positive feedback loop. Sixth, the cyclic lipopeptides in the metabolites of embedded Bacillus subtilis are slowly released in the colon. Their amphiphilic structure can specifically insert into the cell membrane of Clostridium ammoniagenicum, forming transmembrane pores and causing leakage of cell contents. However, they have no such effect on Gram-positive probiotics because their cell wall peptidoglycan layer structure is dense and lacks corresponding lipid targets.

[0013] The aforementioned six mechanisms are not simply superimposed, but rather form a synergistic effect through precise spatiotemporal release design: tea polyphenols, rosmarinic acid, and quercetin mainly function in the terminal ileum to ascending colon region, inhibiting the degradation of residual proteins that have already entered the hindgut; sodium butyrate and yeast cell wall polysaccharides reduce the colonization and activity of ammonia-producing bacteria at the source by regulating the microenvironment pH and microbial community structure; and embedded metabolites provide long-lasting, targeted antibacterial protection. Together, these three mechanisms shift the hindgut nitrogen metabolism from ammonia production to microbial protein synthesis, which can be excreted in feces or further fermented into short-chain fatty acids in the large intestine. These fatty acids can be absorbed and utilized by the host, achieving endogenous nitrogen recycling.

[0014] In another embodiment of the present invention, the compound boar feed additive contains 20 parts of tea polyphenols, 10 parts of rosmarinic acid, 7 parts of quercetin, 15 parts of sodium butyrate, 16 parts of yeast cell wall polysaccharide, 8 parts of embedded Bacillus subtilis metabolites, and 34 parts of carrier. The remaining preparation process and usage methods are the same as above.

[0015] In another embodiment of the present invention, the cyclic lipopeptide in the embedded Bacillus subtilis metabolite is identified by mass spectrometry as a surfactant homologue, with a fatty acid chain length of C13-C15. This structural feature endows it with high selectivity for anaerobic ammonia-producing bacteria. If it is replaced with other Bacillus metabolites such as iturin or fentanyl, the ammonia inhibition effect decreases by more than 30%, and it can produce non-specific inhibition of probiotics.

[0016] The compound boar feed additive of this invention contains no antibiotics, chemically synthesized antibacterial agents, or hormones. All components are derived from natural renewable resources, aligning with industrial policies promoting green farming and sustainable development. Its preparation process is carried out entirely under normal or low-pressure conditions, avoiding high-temperature treatment and maximizing the preservation of the structural integrity and biological activity of the active ingredients.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention resolves the structural contradiction between emission reduction and propagation preservation in existing technologies through a systematic design involving multiple components, targets, and mechanisms. For the first time, this invention scientifically integrates the enzyme-inhibiting functions of tea polyphenols, rosmarinic acid, and quercetin with the intestinal barrier strengthening and pH regulation functions of sodium butyrate, the microbial community regulation function of yeast cell wall polysaccharides, and the targeted antibacterial function of encapsulated Bacillus subtilis metabolites. Through enteric coating and microencapsulation technology, it achieves precise release of each component into specific segments of the intestine, thereby significantly reducing ammonia nitrogen emissions without reducing dietary protein levels or impairing reproductive performance. This technical solution possesses a clear mechanism of action, a reproducible engineered preparation pathway, and significant environmental and economic benefits, demonstrating outstanding substantive characteristics and significant progress. Detailed Implementation

[0018] This invention provides a compound boar feed additive and its preparation process, aiming to solve the technical problem of high ammonia nitrogen emissions and serious environmental pollution caused by the low efficiency of boars in utilizing feed protein. This invention significantly reduces ammonia nitrogen excretion in the feces and urine of boars by constructing a multi-component synergistic system, while maintaining the reproductive performance of breeding boars.

[0019] The technical solution of the present invention will be described in detail below with reference to specific embodiments and comparative examples, so as to ensure that those skilled in the art can fully understand and implement the present invention.

[0020] Example 1: 20 parts tea polyphenols, 10 parts rosmarinic acid, 7 parts quercetin, 15 parts sodium butyrate, 16 parts yeast cell wall polysaccharide, 8 parts encapsulated metabolites, and 34 parts carrier; added at 2.0 kg / ton of complete feed; fed to a 95 kg boar. Preparation process: Dissolving active ingredients → Enteric coating with sodium butyrate → Double-layer encapsulation of metabolites → Carrier adsorption → Multidimensional mixing → Finished product.

[0021] Example 2: 15 parts of tea polyphenols, the rest of the formula and process are the same as in Example 1; Preparation process: Same as in Example 1.

[0022] Example 3: 25 parts of tea polyphenols, the rest of the formula and process are the same as in Example 1; Preparation process: Same as in Example 1.

[0023] Example 4: 10 parts sodium butyrate, the rest of the formula and process are the same as in Example 1; Preparation process: Same as in Example 1.

[0024] Example 5: 18 parts sodium butyrate, the rest of the formula and process are the same as in Example 1; Preparation process: Same as in Example 1.

[0025] Example 6: Add 1.5 kg / ton of complete feed, with the rest of the formula and process the same as in Example 1; Preparation process: Same as in Example 1.

[0026] Example 7: Add 2.5 kg / ton of complete feed, with the rest of the formula and process the same as in Example 1; Preparation process: Same as in Example 1.

[0027] Example 8: The temperature was 30℃, and the rest of the formula and process were the same as in Example 1; Preparation process: Same as in Example 1.

[0028] Comparative Example 1: Only 20 parts tea polyphenols + 80 parts carrier; addition amount 2.0 kg / ton; the rest of the formula and process are the same as in Example 1; Preparation process: dissolving tea polyphenols → adsorption on carrier → mixing → finished product.

[0029] Comparative Example 2: Sodium butyrate was not enteric-coated, and the metabolites were not double-layered; the rest of the formulation and process were the same as in Example 1. Preparation process: Dissolving active ingredients → Direct mixing → Finished product.

[0030] Test method: Emission reduction effect test: Determine the concentration of fecal ammonia nitrogen and the amount of urea nitrogen excreted in urine; count the number of ammonia-producing bacteria in the intestine.

[0031] Reproductive performance testing: Detecting semen density, sperm motility, acrosome integrity rate, and malformation rate; assessing boar libido.

[0032] Stability testing: Monitor the retention rate of active ingredients after feed pelleting; observe the performance degradation of additives after 6 months of storage.

[0033] The test data comparisons are shown in Table 1 and Table 2.

[0034] Table 1. Comparison of decreased fecal ammonia nitrogen, decreased urinary urea nitrogen, and semen density. Test Project Fecal ammonia nitrogen decreased (%) Urine urea nitrogen decreased by (%) <![CDATA[Semen density (×10 8 / mL)]]> Example 1 48.6 43.3 3.2 Example 2 42.5 38 3.1 Example 3 51.2 46.8 3.3 Example 4 40.3 36.5 3 Example 5 50.1 45.2 3.2 Example 6 41.8 37.2 3.1 Example 7 52.3 47.5 3.3 Example 8 51.2 46 3.2 Comparative Example 1 18.5 15.2 3 Comparative Example 2 25.3 22.8 3.1 Table 2 Comparison of Sperm Motility, Acrosome Integrity Rate, and Decline in Ammonia-Producing Bacteria Test Project Sperm motility (%) Acrosome integrity rate (%) Ammonia-producing bacteria decreased (logarithmic units). Example 1 78 85 1.8 Example 2 76 83 1.5 Example 3 79 86 2 Example 4 77 84 1.4 Example 5 78 85 1.9 Example 6 76 83 1.5 Example 7 79 87 2.1 Example 8 77 84 1.8 Comparative Example 1 75 82 0.6 Comparative Example 2 74 81 0.9 Examples 1-8 show ammonia nitrogen reduction of ≥40% and stable reproductive performance, which is far superior to the comparative examples. Comparative example 1 lacks synergy due to the single component, and comparative example 2 has no targeted release, which leads to premature failure of the active ingredient. This confirms that the core process is the key to efficient emission reduction.

[0035] The emission reduction effect is improved when the ratio of tea polyphenols to sodium butyrate is increased (Examples 2→1→3, Examples 4→1→5); the emission reduction effect is optimized with the addition amount in the range of 1.5-2.5 kg / ton; and it still maintains excellent stability under high temperature environment (Example 8).

[0036] The embodiments do not affect semen quality and ensure reproductive performance; they have a significant emission reduction effect and reduce environmental pressure; they are suitable for large-scale farming and are easy to add; they are stable to store and require no special conditions.

[0037] Compared to a single component (Comparative Example 1), the fecal ammonia nitrogen emission reduction of the example was increased by 163%; compared to non-targeted encapsulation (Comparative Example 2), the emission reduction was increased by 92%, solving the industry problem that traditional additives cannot simultaneously achieve emission reduction and propagation.

[0038] The additive described in this invention achieves efficient ammonia nitrogen reduction and reproductive performance protection through multi-component synergy and targeted release, and different parameter combinations can be used to make it suitable for large-scale boar breeding.

[0039] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A composite boar feed supplement, characterized in that, It is composed of the following components by weight: Tea polyphenols 15-25 parts; Rosemary acid 8-12 parts; Quercetin 5-9 parts; Sodium butyrate 10-18 parts; Yeast cell wall polysaccharide 12-20 parts; Embedded Bacillus subtilis metabolites 6-10 parts; And carrier 30-50 parts.

2. The composite boar feed supplement of claim 1, wherein, The tea polyphenols have a gallate content higher than 70% and a total catechin content higher than 85%.

3. The composite boar feed supplement of claim 1, wherein, The quercetin exists in the form of amorphous nanoparticles.

4. The composite boar feed supplement of claim 1, wherein, The sodium butyrate is enteric-coated pellets, and the coating material is acrylic resin Eudragit L100.

5. The composite boar feed supplement of claim 1, wherein, The yeast cell wall polysaccharide has a β-glucan content higher than 40% and a mannose oligosaccharide content higher than 30%, and a molecular weight of 5000-20000 Da.

6. The composite boar feed supplement of claim 1, wherein, The embedded Bacillus subtilis metabolites are obtained by fermentation of Bacillus subtilis and are embedded by sodium alginate-chitosan double-layer microcapsules, and the core active ingredient is a cyclic lipopeptide with a molecular weight of 800-1500 Da, which is slowly released at pH greater than 6.5; the carrier is hydroxypropylated corn starch.

7. The composite boar feed supplement of claim 1, wherein, The tea polyphenols, rosemary acid and quercetin are dissolved in an ethanol solution and uniformly attached to the surface of the carrier.

8. The composite boar feed supplement of claim 1, wherein, The sodium butyrate exists in the form of enteric-coated pellets, and its dissolution rate in pH 6.0 buffer within 2h is less than 5%, and its dissolution rate in pH 7.0 buffer within 30min is higher than 90%.

9. The composite boar feed supplement of claim 5, wherein, The mannose oligosaccharide in the yeast cell wall polysaccharide specifically binds to the fimbrial agglutinin on the surface of ammonia-producing clostridia and Bacteroides, blocking its adhesion to the intestinal epithelium.

10. A process for the preparation of the composite boar feed supplement according to any one of claims 1 to 9, characterized in that, It comprises the following steps: (1) Dissolve tea polyphenols, rosemary acid and quercetin in anhydrous ethanol to form solution A; (2) Coat sodium butyrate with acrylic resin Eudragit L100 to obtain enteric-coated pellets; (3) After ultrafiltration and concentration of Bacillus subtilis fermentation broth, embed it with sodium alginate-chitosan double-layer to obtain embedded Bacillus subtilis metabolites; (4) After pre-mixing yeast cell wall polysaccharide and carrier, add solution A, remove ethanol by vacuum evaporation and dry; (5) Mix the materials obtained in steps (2), (3) and (4) to obtain the finished product.