Feed additive and application thereof in yak breeding

Abstract

The invention relates to the technical field of feed additives, and discloses a feed additive and application thereof in yak breeding. The feed additive comprises the following raw materials in parts by mass: 10-20 parts of mixed bean flour, 5-10 parts of a traditional Chinese medicine extract, 3-5 parts of lactic acid bacteria and 1-3 parts of an acid preparation. The feed additive provided by the invention significantly inhibits the expression of foot and mouth disease virus mRNA and inhibits the replication of foot and mouth disease virus; when the feed additive provided by the invention is added into daily feed for yaks, the foot-and-mouth disease of yaks can be effectively prevented and treated.

Description

Technical Field

[0001] The invention relates to the technical field of feed additives, and in particular to a feed additive and application thereof in yak breeding. Background Art

[0002] Yak is one of the domestic animals with a very limited geographical distribution range in the world. It is mainly distributed in plateau areas centered on the Qinghai-Tibet Plateau, including the Altai Mountains, Kunlun Mountains, Qilian Mountains, Tanggula Mountains, Gangdise Mountains and the Himalayas.

[0003] Due to the extremely complex growth environment of yaks, yaks are often susceptible to some infectious diseases, such as foot-and-mouth disease, glanders, blue ear disease, etc.; among them, foot-and-mouth disease is an acute, febrile, highly contagious disease caused by the foot-and-mouth disease virus, and is listed as the first Class A infectious disease by the International Office of Epizootics. This is because foot-and-mouth disease has many transmission routes and spreads quickly. It has broken out many times around the world, causing huge economic and political losses; therefore, it is particularly important to effectively prevent and control foot-and-mouth disease in yaks.

[0004] Yak feed is the main food for yaks. If feed additives that can effectively inhibit the replication of foot-and-mouth disease virus are added to yak feed, foot-and-mouth disease in yaks can be effectively prevented and treated. Summary of the invention

[0005] The purpose of the present invention is to provide a feed additive which can effectively inhibit the replication of foot-and-mouth disease virus. When the feed additive is added into yak feed, the foot-and-mouth disease of yaks can be effectively prevented and treated.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] One of the technical solutions of the present invention:

[0008] A feed additive comprises the following raw materials in parts by weight: 10 to 20 parts of mixed soybean powder, 5 to 10 parts of traditional Chinese medicine extracts, 3 to 5 parts of lactic acid bacteria and 1 to 3 parts of acid preparations.

[0009] Furthermore, the method for preparing the mixed bean powder comprises the following steps: mixing soybeans and peas, and grinding them to obtain the mixed bean powder.

[0010] Furthermore, the mass ratio of soybeans to peas is 2:1.

[0011] Furthermore, the preparation method of the Chinese medicine extract comprises the following steps: mixing honeysuckle, dandelion, isatis root, coptis root, forsythia, schizonepeta and indigo to obtain a mixed Chinese medicine, then adding the mixed Chinese medicine into water, simmering over low heat, filtering, and drying to obtain the Chinese medicine extract.

[0012] Furthermore, the mass ratio of the honeysuckle, dandelion, isatis root, coptis root, forsythia suspensa, schizonepeta and indigo is (15-25):(10-20):(10-20):(5-15):(5-15):(1-10):(1-5).

[0013] Furthermore, the mass volume ratio of the mixed traditional Chinese medicine and water is 1g:20mL.

[0014] Furthermore, the slow fire simmering time is 2 hours.

[0015] Furthermore, the method for preparing the acid preparation comprises the following steps: mixing malic acid, citric acid and lactic acid to obtain the acid preparation.

[0016] Furthermore, the mass ratio of malic acid, citric acid and lactic acid is 1:(0.8-1.2):(0.5-1).

[0017] The second technical solution of the present invention:

[0018] The preparation method of the above feed additive comprises the following steps:

[0019] The mixed soybean powder, the Chinese medicinal extract, the lactic acid bacteria and the acid preparation are mixed to obtain the feed additive.

[0020] The third technical solution of the present invention:

[0021] The application of the above feed additive in yak breeding is specifically: adding the above feed additive to the daily feed of the yaks to feed the yaks.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The feed additive provided by the present invention significantly inhibits the expression of foot-and-mouth disease virus mRNA and inhibits the replication of foot-and-mouth disease virus; adding the feed additive provided by the present invention to the daily feed of yaks can effectively prevent and treat foot-and-mouth disease in yaks. DETAILED DESCRIPTION

[0024] Now, various exemplary embodiments of the present invention are described in detail, and this detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention. It should be understood that the terms described in the present invention are only for describing specific embodiments and are not used to limit the present invention.

[0025] In addition, for the numerical range in the present invention, it is understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0026] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0027] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0028] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0029] In the following examples and comparative examples, all the raw materials used were commercially available;

[0030] A method for preparing a feed additive comprises the following steps:

[0031] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0032] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of (15-25):(10-20):(10-20):(5-15):(5-15):(1-10):(1-5) to obtain a mixed Chinese medicine;

[0033] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0034] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of malic acid, citric acid and lactic acid of 1:(0.8-1.2):(0.5-1) to obtain an acid preparation;

[0035] 5) Weigh each raw material according to the following mass parts:

[0036] Mix 10-20 parts of soybean powder, 5-10 parts of Chinese herbal medicine extract, 3-5 parts of lactic acid bacteria and 1-3 parts of acid preparation;

[0037] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0038] Example 1

[0039] A feed additive

[0040] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0041] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 15:10:10:5:5:1:1 to obtain a mixed Chinese medicine;

[0042] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0043] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:0.8:0.5 to obtain an acid preparation;

[0044] 5) Weigh each raw material according to the following mass parts:

[0045] Mix 10 parts of soybean powder, 5 parts of Chinese herbal extract, 3 parts of lactic acid bacteria and 1 part of acid preparation;

[0046] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0047] Example 2

[0048] A feed additive

[0049] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0050] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:10:5:2 to obtain a mixed Chinese medicine;

[0051] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0052] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0053] 5) Weigh each raw material according to the following mass parts:

[0054] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0055] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0056] Example 3

[0057] A feed additive

[0058] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0059] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 25:20:20:15:15:10:5 to obtain a mixed Chinese medicine;

[0060] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0061] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1.2:1 to obtain an acid preparation;

[0062] 5) Weigh each raw material according to the following mass parts:

[0063] Mix 20 parts of soybean powder, 10 parts of Chinese herbal extract, 5 parts of lactic acid bacteria and 3 parts of acid preparation;

[0064] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0065] Comparative Example 1

[0066] A feed additive

[0067] 1) Grind soybeans through a 20-mesh sieve to obtain soybean powder;

[0068] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:10:5:2 to obtain a mixed Chinese medicine;

[0069] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0070] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0071] 5) Weigh each raw material according to the following mass parts:

[0072] 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0073] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0074] Comparative Example 2

[0075] 1) Grind peas through a 20-mesh sieve to obtain bean powder;

[0076] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:10:5:2 to obtain a mixed Chinese medicine;

[0077] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0078] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0079] 5) Weigh each raw material according to the following mass parts:

[0080] 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0081] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0082] Comparative Example 3

[0083] A feed additive

[0084] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0085] 2) mixing honeysuckle, dandelion, isatis root, forsythia, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:5:2 to obtain a mixed Chinese medicine;

[0086] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0087] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0088] 5) Weigh each raw material according to the following mass parts:

[0089] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0090] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0091] Comparative Example 4

[0092] A feed additive

[0093] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0094] 2) mixing honeysuckle, dandelion, isatis root, coptis root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:5:2 to obtain a mixed Chinese medicine;

[0095] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0096] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0097] 5) Weigh each raw material according to the following mass parts:

[0098] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0099] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0100] Comparative Example 5

[0101] A feed additive

[0102] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0103] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia suspensa and indigo naturalis in a mass ratio of 20:15:15:10:10:2 to obtain a mixed Chinese medicine;

[0104] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0105] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0106] 5) Weigh each raw material according to the following mass parts:

[0107] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0108] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0109] Comparative Example 6

[0110] A feed additive

[0111] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0112] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia suspensa and schizonepeta in a mass ratio of 20:15:15:10:10:5 to obtain a mixed Chinese medicine;

[0113] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0114] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0115] 5) Weigh each raw material according to the following mass parts:

[0116] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0117] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0118] Comparative Example 7

[0119] A feed additive

[0120] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0121] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:10:5:2 to obtain a mixed Chinese medicine;

[0122] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0123] 4) mixing malic acid and lactic acid in a mass ratio of 1:0.8 to obtain an acid preparation;

[0124] 5) Weigh each raw material according to the following mass parts:

[0125] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0126] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0127] Comparative Example 8

[0128] A feed additive

[0129] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0130] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:10:5:2 to obtain a mixed Chinese medicine;

[0131] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0132] 4) mixing malic acid and citric acid in a mass ratio of 1:1 to obtain an acid preparation;

[0133] 5) Weigh each raw material according to the following mass parts:

[0134] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0135] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0136] Comparative Example 9

[0137] A feed additive

[0138] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0139] 2) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0140] 3) Weigh each raw material according to the following mass parts:

[0141] Mix 15 parts of soybean powder, 4 parts of lactic acid bacteria and 2 parts of acid preparation;

[0142] 4) Mixing the raw materials weighed in step 3) to obtain the feed additive.

[0143] Comparative Example 10

[0144] A feed additive

[0145] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0146] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:10:5:2 to obtain a mixed Chinese medicine;

[0147] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0148] 4) Weigh each raw material according to the following mass parts:

[0149] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract and 4 parts of lactic acid bacteria;

[0150] 5) Mixing the raw materials weighed in step 4) to obtain the feed additive.

[0151] Comparative Example 11

[0152] A feed additive

[0153] 1) mixing soybeans and peas in a mass ratio of 2:1, grinding the soybeans and peas through a 20-mesh sieve to obtain mixed soybean powder;

[0154] 2) mixing honeysuckle, dandelion, isatis root, coptis root, forsythia root, schizonepeta and indigo naturalis in a mass ratio of 20:15:15:10:10:5:2 to obtain a mixed Chinese medicine;

[0155] 3) adding the mixed Chinese medicine obtained in step 2) into water at a mass volume ratio of the mixed Chinese medicine to water of 1 g: 20 mL, simmering for 2 h, filtering, and drying to obtain a Chinese medicine extract;

[0156] 4) mixing malic acid, citric acid and lactic acid in a mass ratio of 1:1:0.8 to obtain an acid preparation;

[0157] 5) Weigh each raw material according to the following mass parts:

[0158] Mix 15 parts of soybean powder, 8 parts of Chinese herbal extract and 2 parts of acid preparation;

[0159] 6) Mixing the raw materials weighed in step 5) to obtain the feed additive.

[0160] Effect verification

[0161] The feed additives prepared in Examples 1 to 3 and Comparative Examples 1 to 11 were tested for the inhibition effect of foot-and-mouth disease virus replication, and the testing method was as follows:

[0162] 1. Preparation of PK-15 cells infected with foot-and-mouth disease virus

[0163] PK-15 cells were plated in a single well of a 24-well plate. After the cells grew into a monolayer, the culture medium was discarded and 0.5 MOI foot-and-mouth disease virus solution was inoculated. The cells were cultured at 37°C for 1 h and the virus solution was discarded.

[0164] 2. Addition of feed additives

[0165] The feed additives prepared in Examples 1 to 3 and Comparative Examples 1 to 11 were added to water to form a mass concentration of 0.05 g·mL -1 The feed additive suspension was then added dropwise to the wells where the virus solution was discarded in step 1 according to an inoculum size of 20 μg, and cultured at a constant temperature of 37°C for 12 h;

[0166] 3. Detection of mRNA expression level of foot-and-mouth disease virus

[0167] The PK-15 cells cultured in step 2 were washed with PBS, and RNA was extracted, reverse transcribed, and PCR was performed;

[0168] The results of the mRNA expression level detection of foot-and-mouth disease virus are shown in Table 1 ;

[0169] Table 1 Results of detection of mRNA expression level of foot-and-mouth disease virus

[0170]

[0171] Note: Negative control is without any feed additives;

[0172] It can be seen from the data in Table 1 that the feed additive provided by the present invention significantly inhibits the expression of foot-and-mouth disease virus mRNA and inhibits the replication of foot-and-mouth disease virus.

[0173] Application Examples

[0174] According to the addition amount of the feed additive of 5wt.% of the daily feed of the yaks, the feed additive prepared in Example 2 was added to the daily feed of the yaks, and 5 sick yaks were fed. The symptoms of the yaks are shown in Table 2;

[0175] Table 2 Disease status of yak

[0176]

[0177]

[0178] It can be seen from the data in Table 2 that adding the feed additive provided by the present invention to the daily feed of yaks can effectively prevent and treat foot-and-mouth disease in yaks.

[0179] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A feed additive, characterized in that: The invention comprises the following raw materials in parts by weight: 10 to 20 parts of mixed bean powder, 5 to 10 parts of traditional Chinese medicine extract, 3 to 5 parts of lactic acid bacteria and 1 to 3 parts of acid preparation.

2. A feed additive according to claim 1, characterized in that: The method for preparing the mixed bean powder comprises the following steps: mixing soybeans and peas, and grinding them to obtain the mixed bean powder.

3. A feed additive according to claim 2, characterized in that: The mass ratio of soybeans to peas is 2:

1.

4. A feed additive according to claim 1, characterized in that: The preparation method of the Chinese medicine extract comprises the following steps: mixing honeysuckle, dandelion, isatis root, coptis root, forsythia, schizonepeta and indigo to obtain a mixed Chinese medicine, then adding the mixed Chinese medicine into water, simmering over low heat, filtering and drying to obtain the Chinese medicine extract.

5. A feed additive according to claim 4, characterized in that: The mass ratio of honeysuckle, dandelion, isatis root, coptis root, forsythia, schizonepeta and indigo is (15-25): (10-20): (10-20): (5-15): (5-15): (1-10): (1-5); the mass volume ratio of the mixed traditional Chinese medicine and water is 1g: 20mL; and the simmering time is 2h.

6. A feed additive according to claim 1, characterized in that: The method for preparing the acid preparation comprises the following steps: mixing malic acid, citric acid and lactic acid to obtain the acid preparation.

7. A feed additive according to claim 6, characterized in that: The mass ratio of the malic acid, the citric acid and the lactic acid is 1:(0.8-1.2):(0.5-1).

8. A method for preparing the feed additive according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: mixing mixed bean powder, Chinese medicinal extract, lactic acid bacteria and acid preparation to obtain the feed additive.

9. Use of the feed additive according to any one of claims 1 to 7 in yak breeding, characterized in that: The specific application is: adding the feed additive described in any one of claims 1 to 7 into the daily feed of yaks to feed the yaks.

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