Rumen-bypass composition and method for preventing mastitis using same

Abstract

To provide a method for preventing mastitis that can be performed for ruminants through simpler operations such as feeding compared to vaccination, and that exhibits an enhanced operation efficiency and an increased preventive effect.SOLUTION: A rumen-bypass composition, which contains at least a glutamate salt and has a rumen-bypass glutamate content of 15 wt.% or more, is fed to a ruminant.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a rumen bypass composition and a method for preventing mastitis using the same, and more particularly to a rumen bypass composition that can prevent mastitis by feeding it to ruminants, and a method for preventing mastitis using the same. [Background technology]

[0002] Mastitis is an inflammation of the mammary glands of mammals, including dairy cows, caused by bacterial infection. Bacteria enter the animal through the teat canal and cause acute, clinical or subclinical mastitis. Staphylococcus aureus, agalactococcus, Escherichia coli, Pseudomonas aeruginosa, etc. are known as causative pathogens of mastitis in dairy cows. Mastitis is more likely to develop when the resistance of dairy cows is reduced, or when hygiene management at the time of milking or in the livestock barn is insufficient. Mastitis increases the number of somatic cells in the milk and reduces milk production. Mastitis in dairy cows is the most economically costly disease for dairy farming, and losses due to reduced milk quality, disposal of raw milk during treatment, treatment costs, feed costs during treatment, and reduced milk yield are enormous for dairy farmers. Furthermore, in many cases, treatment requires isolating the infected cow from the herd, which increases the dairy farmer's work hours and reduces motivation due to mental distress.

[0003] As a measure against mastitis in dairy cows, dairy farmers disinfect teats, wash milking machines, clean cow beds to keep them clean, optimize milking procedures, improve nutritional conditions, and strive to detect mastitis early (e.g., Non-Patent Document 1). Prevention of mastitis with intramuscular (Non-Patent Document 2) and mucosal (Non-Patent Document 3) vaccines is also being considered. Furthermore, prevention of inflammation by feeding feed containing active ingredients is also being considered for the purpose of increasing resistance to pathogens. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] "Hyogo Prefecture Milk Quality Improvement Manual - Correct Milking Procedures", revised edition compiled by the Hyogo Prefecture Dairy Promotion Council (March 2016) [Non-Patent Document 2] ▲Takahashi Toshihiko et al., “Effect of simultaneous administration of bovine injectable mastitis vaccine to all cattle to prevent mastitis,” J. Rakuno Gakuen Univ., 47 (2):59~64 (2023) [Non-Patent Document 3] Hiroya Nagasawa, Livestock Technology, vol. 2020 (5) p.28-32, 2020 Summary of the Invention [Problem to be solved by the invention]

[0005] However, despite these various measures, the incidence of mastitis in dairy cows in Japan is increasing year by year. In addition, the work involved in preventing and early detection of mastitis is difficult to mechanize and takes a lot of time, and even if a mastitis vaccination is administered, mastitis may still develop depending on the pathogen. In spite of the difficulties involved, the conventional methods have not been able to achieve their goals.

[0006] The present invention has been made in consideration of such conventional problems, and aims to provide a method for preventing mastitis in ruminants that can be performed by simpler procedures such as feeding than vaccination, is highly efficient, and has a high preventive effect. [Means for solving the problem]

[0007] As a result of intensive research to solve the above-mentioned problems, the inventors first discovered that the blood glutamate concentration of cows with mastitis is lower than that of healthy cows, and hypothesized that maintaining a constant blood glutamate concentration may make it possible to prevent mastitis or alleviate its severity. However, even if glutamate is fed directly to ruminants, it is broken down by microorganisms that live mainly in the rumen of the first stomach (hereinafter referred to as "rumen microorganisms"). Rumen microorganisms are a microbial flora consisting of bacteria, protozoa (protozoa), anaerobic fungi, etc. In addition, since glutamic acid is an essential amino acid, it is not generally provided as a nutrient source, and the effects of providing it have not received much attention. The inventors have therefore confirmed that by feeding a glutamic acid preparation that is coated to prevent glutamic acid from being released in the nearly neutral range of the first stomach and broken down by ruminal microorganisms, and then rapidly released in the acidic range of the fourth stomach, high blood glutamic acid concentrations can be maintained and the incidence of mastitis can be reduced. Furthermore, the present inventors have developed a glutamate-containing composition having a rumen-bypassing glutamic acid content within a specified range.

[0008] That is, the present invention includes the following aspects. Aspect (1) of the present invention is a rumen-bypass composition which contains at least a glutamate and has a rumen-bypassing glutamic acid content of 15% by weight or more.

[0009] In an embodiment (2) of the present invention, the rumen bypass composition of the embodiment (1) is a molded product made of a melt-kneaded product containing 15 to 75% by weight of glutamate, 20 to 80% by weight of a fatty acid metal soap having 8 to 24 carbon atoms, and 1 to 20% by weight of a fatty acid or fatty acid ester having a melting point of 60 to 80°C.

[0010] Aspect (3) of the present invention relates to the rumen bypass composition of aspect (2), wherein the glutamate is sodium glutamate, the fatty acid metal soap has an endothermic peak in the range of 60 to 130°C by differential scanning calorimetry, and the fatty acid or fatty acid ester is a saturated fatty acid or a saturated fatty acid triglyceride.

[0011] In an embodiment (4) of the present invention, the lumen bypass composition according to any one of embodiments (1) to (3) is in the form of a lump.

[0012] Aspect (5) of the present invention relates to the rumen bypass composition of any one of aspects (1) to (4), wherein the rumen bypass glutamic acid content is 20 to 40 wt %.

[0013] A sixth aspect of the present invention is a method for preventing mastitis, which comprises feeding a rumen bypass composition according to any one of the first to fifth aspects to a ruminant.

[0014] A seventh aspect of the present invention relates to the method for preventing mastitis according to the sixth aspect, wherein the amount of rumen-bypassing glutamic acid fed to a ruminant per day is 20 to 100 g.

[0015] In the present invention, a "ruminant" is a mammalian animal having multiple stomachs. Ruminants have the ability to soften and digest food in the first stomach (rumen) and regurgitate the semi-digested mass. The semi-digested mass is chewed again for digestion in the first stomach or multiple other stomachs. Ruminants include, for example, lactating animals such as cows, sheep, and goats, with dairy cows and goats being preferred for the purpose of producing raw milk. Effect of the Invention

[0016] By feeding the rumen bypass composition of the present invention to ruminants, mastitis can be prevented. The reason is unclear, but is presumed to be as follows. First, the glutamate contained in the rumen bypass composition fed to ruminants is not released in the first stomach, which is in a nearly neutral region, but is quickly released in the fourth stomach, which is acidic. The released glutamate is absorbed into the body, maintaining a high blood glutamate concentration and activating the antibodies of the animal that ingested it. Not only does the antibody become activated to improve resistance to pathogens, but the intake of glutamate suppresses the inflammatory response of mastitis, making it possible to prevent mastitis or alleviate its severity. In addition, glutamate is also used as a nutrient source for the ruminants that are fed it. [Brief description of the drawings]

[0017] [Figure 1] Figure 1 is a graph showing the change in the incidence of mastitis from 15 days before the start of feeding. [Diagram 2]Figure 2 is a graph comparing the trend in mastitis incidence rate based on the first day of feeding (feeding start date) with that in cases where feeding was not performed. [Diagram 3] Figure 3 is a graph comparing the incidence of mastitis 45 days after the start of feeding with that of cows not fed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described, however, the present invention is not limited to the embodiment described in this specification, and various modifications are possible without departing from the gist of the present invention. In this specification, a numerical range defined using the symbol "~" is intended to include both the upper and lower limits of the range. For example, "2~5" means 2 or more and 5 or less. Furthermore, in the numerical ranges described in this specification, the upper limit or lower limit of the numerical ranges can be replaced with values ​​shown in the examples or values ​​that are uniquely derived from the examples.

[0019] <Lumen bypass composition> The rumen bypass composition of the present invention contains at least glutamate, and the rumen bypassing glutamic acid content is 15% by weight or more, preferably 20 to 40% by weight. If the rumen bypassing glutamic acid content is too low, a large amount of the rumen bypass composition must be fed to obtain the effect of glutamate, which may cause a large burden on the digestive organs of the fed ruminant and may be uneconomical. On the other hand, if the rumen bypassing glutamic acid content is too high, glutamate may be difficult to release not only in the rumen but also in the fourth stomach, which may cause a large burden on the digestive organs of the fed ruminant and may be uneconomical, as described above. However, the upper limit of the rumen bypassing glutamic acid content is not necessarily required to be specified, since it is affected by the type and amount of components other than glutamate constituting the rumen bypass composition. The rumen bypass composition of the present invention is a composition for feeding to ruminants, which is intended to be fed (orally administered) to ruminants. Furthermore, there are no particular limitations on the components other than glutamate constituting the rumen bypass composition of the present invention.

[0020] The rumen-bypassed glutamic acid content is the glutamic acid content in a composition after it has been allowed to reside in the rumen for a specified period of time, and in the present invention, it can be measured by the following method. Accurately weigh 2 g of sample into an Erlenmeyer flask and immerse in 100 g of ion-exchanged water. Shake at 40°C for 6 hours, then filter and blow dry the filter residue. Quantify glutamic acid in the dried residue, and calculate the rumen-bypassed glutamic acid content using the following formula: Rumen-bypassing glutamic acid content (wt%) = weight of glutamic acid in residue (g) / weight of sample (g) × 100 Methods for quantifying glutamic acid include, for example, high performance liquid chromatography and calculation from total nitrogen (Kjeldahl method, etc.) (provided that the nitrogen source is only nitrogen derived from glutamate).

[0021] Next, one example of a preferred embodiment of the lumen bypass composition of the present invention will be described. The lumen bypass composition of this embodiment is a molded body made of a molten kneaded product containing 15 to 75 weight % glutamate, 20 to 80 weight % fatty acid metal soap having 8 to 24 carbon atoms, and 1 to 20 weight % fatty acid or fatty acid ester having a melting point of 60 to 80°C.

[0022] [Glutamate] Examples of glutamic acid salts include sodium glutamate, potassium glutamate, calcium glutamate, magnesium glutamate, etc., and among these, sodium glutamate is preferable in terms of availability. As glutamic acid salts, two or more kinds of glutamic acid salts may be used.

[0023] [Fatty acid metal soap] The raw material fatty acid constituting the fatty acid metal soap having 8 to 24 carbon atoms may be either saturated or unsaturated. Examples of such fatty acids include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, stearic acid, and arachic acid, and are preferably straight-chain saturated fatty acids having 12 to 22 carbon atoms. There are no limitations on the raw materials and manufacturing methods for the fatty acid metal soap. For example, fatty acid metal soaps can be manufactured using mixed fatty acids produced by hydrolyzing fats and oils such as beef tallow, lard, rapeseed oil, soybean oil, palm oil, palm kernel oil, etc. as the starting material, and manufactured by a direct method, a double decomposition method, or the like. Examples of fatty acid metal soaps include calcium salts and magnesium salts. Since the fatty acid metal soap is used as a component of milk, calcium salts are preferred.

[0024] Among fatty acid metal soaps, those having an endothermic peak in a range of 60 to 130°C by differential scanning calorimetry are preferred, and those having an endothermic peak in a range of 90 to 125°C are more preferred. In particular, fatty acid calcium salts having an endothermic peak in a range of 60 to 130°C are easy to process into a certain shape as feed, and are also desirable for protecting glutamate. Examples include palm oil fatty acid calcium and calcium stearate. A differential scanning calorimeter is used to measure the endothermic peak of fatty acid metal soap by differential scanning calorimetry (DSC), and the measurement is performed under the conditions of a sample amount of 10 mg and a heating rate of 2° C. / min.

[0025] While fatty acid metal soaps exhibit stable water repellency in the neutral range, they dissociate into fatty acids and metals such as calcium at a pH of around 2. Therefore, the rumen bypass composition of the present embodiment containing a fatty acid metal soap protects glutamate in the rumen or water in the nearly neutral range, making it difficult to release the glutamate, while being able to quickly release the glutamate in the acidic abomasum. The fatty acid metal soaps can be used alone or in combination of two or more.

[0026] [Fatty acids or fatty acid esters] The fatty acid and fatty acid ester used in this embodiment have a melting point of 60 to 80°C, preferably 60 to 75°C, and more preferably 60 to 70°C. If the melting point is less than 60°C, it is difficult to solidify into a certain shape, and when a load is applied, lumps of a certain shape tend to adhere to each other and become block-like, which may make handling inconvenient. On the other hand, if the melting point is more than 80°C, the surface of the glutamate remains covered with a hydrophobic substance, making it difficult to digest in the fourth stomach, and the glutamate that is not released in the rumen cannot be absorbed in the intestine and is excreted as feces, which may prevent effective use of the glutamate. The melting point can be measured in accordance with the Standard Method for Analysis of Fats, Oils and Related Materials, "2.2.4.2 Melting Point (Slip Melting Point)."

[0027] The fatty acids include single fatty acids and mixed fatty acids. Single fatty acids include linear saturated fatty acids having 16 to 22 carbon atoms, such as palmitic acid, stearic acid, arachidic acid, and behenic acid. Mixed fatty acids include mixed fatty acids consisting of saturated fatty acids having 6 to 24 carbon atoms, such as mixed fatty acids obtained by hydrolysis of fats and oils, such as beef tallow, lard, rapeseed oil, soybean oil, palm oil, and palm kernel oil. Among these fatty acids, preferred are linear saturated fatty acids having 16 to 18 carbon atoms and a melting point of 60 to 80° C. Examples include palmitic acid and stearic acid.

[0028] The fatty acid ester includes not only the ester of the above fatty acid and polyhydric alcohol, but also hardened oils and fats obtained by hydrogenating animal and vegetable oils and fats. The single fatty acid used as the raw material of the ester includes a linear saturated fatty acid having 14 to 22 carbon atoms, such as myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, etc., and preferably a linear saturated fatty acid having 14 to 18 carbon atoms and a mixed fatty acid thereof. The polyhydric alcohol used as the raw material of the ester includes, for example, glycerin, propylene glycol, butylene glycol, polyethylene glycol, etc., with glycerin being preferred. Therefore, the ester is preferably a saturated fatty acid triglyceride, which is an ester of a linear saturated fatty acid having 14 to 18 carbon atoms and glycerin. Examples of hardened oils and fats obtained by hydrogenating animal and vegetable oils and fats include hardened oils and fats obtained from oils and fats such as beef tallow, lard, soybean oil, rapeseed oil, jojoba oil, rice oil, and palm oil, and preferably extremely hardened oils and fats obtained from soybean oil, rapeseed oil, jojoba oil, and rice oil, and have a melting point of 60 to 80°C.

[0029] The fatty acids can be used alone or in combination of two or more kinds. The fatty acid esters can be used alone or in combination of two or more kinds. Furthermore, fatty acids and fatty acid esters can be used in combination.

[0030] [Content of each ingredient] The content of glutamate is 15-75% by weight, preferably 25-60% by weight, based on the total composition. If the content of glutamate is too low, a large amount of the rumen bypass composition must be fed to obtain the effect of glutamate, which may place a heavy burden on the digestive organs of the fed ruminant and may be uneconomical. On the other hand, if the content of glutamate is too high, it becomes difficult to solidify into a certain shape, and most of the fed glutamate may be released in the rumen and decomposed by ruminal microorganisms.

[0031] The content of the fatty acid metal soap is 20-80% by weight, preferably 30-75% by weight, based on the total weight of the composition. If the content of the fatty acid metal soap is too low, it becomes difficult to solidify into a certain shape, and the glutamate fed may be consumed in the rumen. On the other hand, if the content of the fatty acid metal soap is too high, a large amount of the rumen bypass composition must be fed to obtain the effect of the glutamate, which places a heavy burden on the digestive organs of the fed ruminant and may be uneconomical.

[0032] The content of fatty acid or fatty acid ester is 1-20% by weight, preferably 2-10% by weight, based on the total composition. If the content of fatty acid or fatty acid ester is too low, glutamate may be eluted from the surface of the molded body and consumed in the rumen. On the other hand, if the content of fatty acid or fatty acid ester is too high, the composition may be extremely softened and liquid when heated, which may cause manufacturing problems such as the inability to remove the solidified product from the twin-screw extruder.

[0033] The rumen bypass composition of the present embodiment may contain additives as necessary, and may contain vitamins, other amino acids (salts), minerals, etc., to the extent that the effects of the present invention are not impaired. When the lumen bypass composition of the present embodiment contains an additive, the content of the additive is 4% by weight or less, and preferably 2% by weight or less, based on the total weight of the composition.

[0034] The total content of each component constituting the lumen bypass composition of this embodiment is 100% by weight.

[0035] [Preparation of Lumen Bypass Composition] In the present embodiment, the glutamic acid salt, fatty acid metal soap, fatty acid or fatty acid ester, and further additives are precisely weighed, mixed, and then heated to melt. The molten mixture obtained by further mixing is cooled to obtain a molded product. In order to properly protect the surface of glutamic acid (salt) and obtain bypass glutamic acid, it is preferable to mix the components, knead them using a twin-screw extruder, and cool and cut the extruded product to obtain a lump-shaped lumen bypass composition having a certain shape. The lumen bypass composition is in the form of a lump, which can suppress the elution and consumption of glutamic acid salt in the rumen. The lump-shaped product is preferably, for example, a tablet, pellet, or spherical shape.

[0036] When the lumen bypass composition of this embodiment is in the form of a tablet, pellet, or sphere, it has a thickness (diameter) of 2 to 10 mm, a length (height) of 2 to 10 mm, and a weight of 0.03 to 2 g.

[0037] <How to prevent mastitis> The method for preventing mastitis of the present invention is characterized by feeding a rumen bypass composition of the present invention, including the rumen bypass composition shown in the above embodiments, to a ruminant. The period for feeding the rumen bypass composition of the present invention is preferably from early lactation to late lactation. There is no particular restriction on the start time of feeding, but feeding is preferably performed before the day milking starts. Also, feeding of the rumen bypass composition may be stopped on the day milking ends. The rumen bypass composition of the present invention may be fed together with ordinary roughage or may be fed separately from ordinary roughage.

[0038] The rumen bypass composition of the present invention is preferably fed in an amount calculated from the rumen bypassing glutamic acid content so that the amount of rumen bypassing glutamic acid fed per day per ruminant is 20 to 100 g. If the amount of rumen bypassing glutamic acid fed per day is too small, the preventive effect against mastitis may not be obtained, whereas if the amount fed is too large, the burden on the digestive organs of the fed ruminant may be large, and this may be uneconomical. EXAMPLES

[0039] The present invention will now be described more specifically with reference to examples and comparative examples. Table 1 shows the endothermic peaks obtained by differential scanning calorimetry (DSC) of the fatty acid metal soaps used in the examples and comparative examples. Table 2 shows the melting points of the fatty acids and fatty acid esters used in the examples and comparative examples. The endothermic peak and melting point were measured by differential scanning calorimetry (DSC) as described above.

[0040] [Table 1]

[0041] [Table 2]

[0042] Example 1 50 parts by weight of sodium glutamate (hereinafter simply referred to as "parts"), 45 parts of calcium palm oil fatty acid, and 5 parts of hardened rapeseed oil were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0043] Example 2 40 parts of sodium glutamate, 55 parts of calcium palm oil fatty acid, and 5 parts of hardened rapeseed oil were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0044] Example 3 50 parts of sodium glutamate, 40 parts of calcium palm oil fatty acid, and 10 parts of hardened rapeseed oil were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0045] Example 4 50 parts of sodium glutamate, 45 parts of calcium palm oil fatty acid, and 5 parts of palmitic acid were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0046] Example 5 50 parts of sodium glutamate, 45 parts of calcium stearate, and 5 parts of hardened rapeseed oil were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0047] Comparative Example 1 50 parts of sodium glutamate and 50 parts of calcium palm oil fatty acid were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition having a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0048] Comparative Example 2 30 parts of sodium glutamate, 69.5 parts of calcium palm oil fatty acid, and 0.5 parts of hardened rapeseed oil were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0049] Comparative Example 3 50 parts of sodium glutamate, 47 parts of calcium palm oil fatty acid, and 3 parts of hardened rapeseed oil were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0050] Comparative Example 4 50 parts of sodium glutamate, 45 parts of calcium palm oil fatty acid, and 5 parts of hardened palm oil fatty acid were mixed. The mixture was fed into a twin-screw kneading extruder and melt-extruded through a die with a hole diameter of 3 mm. The mixture was then cut with a cutter and dried by blowing air at room temperature to obtain a pellet-shaped lumen bypass composition with a thickness (diameter) of 3 mm, a length (height) of 3 to 10 mm, and a weight of 0.03 to 0.1 g.

[0051] The rumen bypass compositions obtained in the Examples and Comparative Examples were examined for the rumen bypass glutamic acid content. The rumen bypass glutamic acid content was measured as described above. The results are shown in Table 3.

[0052] [Table 3]

[0053] [Lumen bypass composition application test] To confirm the potential of the rumen bypass composition of the present invention to prevent mastitis, the following experiment was conducted. At Center A, a dairy farm in Miyagi Prefecture, 80 lactating dairy cows were fed the rumen bypass composition of Example 1. All cows were fed the composition, and clinical evaluation was performed by comparing data before and after feeding with data from the same month of the previous year. The daily feeding amount of the rumen bypass composition shown in Example 1 per head was 200 g / head / day (the feeding amount of rumen bypass glutamic acid was calculated as 50.2 g / head / day), and the cows were fed with a top dress around 11:00 am every day. The number of cows that developed mastitis during the period was counted based on the treatment history, and the number of cows that developed mastitis in 15 days relative to the total number of cows was defined as the incidence rate (Figure 1). In addition, the number of cows treated between 15 days before the start of the test and the start day of the test was set as 100, and the number of treated cows was counted every 15 days to calculate the mastitis incidence rate, which was further compared with the control group (cows not fed in the same month of the previous year) (Figures 2 and 3). The number of individuals that developed mastitis was counted, and the incidence rate in each group was calculated. The incidence rate was clearly lower than before feeding the rumen bypass composition shown in Example 1. The incidence rate was particularly low one month after feeding (Figure 1). Furthermore, when comparing the trend in incidence rate in the same month last year (■) with the trend in the test this year (◯), it is clear that there was a significant decrease in the white (◯) test group (Figure 2). Furthermore, when the incidence rate of mastitis 45 days after the start of feeding was compared with that in the case of no feeding, the incidence rate was significantly lower (Figure 3).

Claims

1. A rumen-bypassing composition containing at least a glutamate and having a rumen-bypassing glutamic acid content of 15% by weight or more.

2. The lumen bypass composition according to claim 1, which is a molded product made of a molten kneaded product containing 15 to 75 weight % glutamate, 20 to 80 weight % fatty acid metal soap having 8 to 24 carbon atoms, and 1 to 20 weight % fatty acid or fatty acid ester having a melting point of 60 to 80°C.

3. The rumen bypass composition of claim 2, wherein the glutamate is sodium glutamate, the fatty acid metal soap has an endothermic peak in the range of 60 to 130°C by differential scanning calorimetry, and the fatty acid or fatty acid ester is a saturated fatty acid or a saturated fatty acid triglyceride.

4. The lumen bypass composition according to any one of claims 1 to 3, which is in the form of a lump.

5. 4. The rumen bypass composition according to claim 1, wherein the rumen-bypassing glutamic acid content is 20 to 40% by weight.

6. A method for preventing mastitis, which comprises feeding the rumen bypass composition according to any one of claims 1 to 3 to a ruminant.

7. 7. The method for preventing mastitis according to claim 6, wherein the amount of rumen-bypassing glutamic acid fed to a ruminant per day is 20 to 100 g.

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