Feed additive for improving marbling grade of beef as well as preparation method and application of feed additive

Abstract

The invention discloses a feed additive for improving the marbling grade of beef as well as a preparation method and application of the feed additive, belongs to the technical field of feed additives, and provides the feed additive for improving the marbling grade of the beef. Comprising the following components in parts by weight: 0.02 to 0.06 part of puerarin, 0.05 to 0.15 part of sea buckthorn flavone, 0.45 to 0.65 part of bamboo leaf flavone, 0.8 to 1.2 parts of saccharomyces cerevisiae, 1.5 to 2.5 parts of rapeseed oil and 2.6 to 3.4 parts of olive oil. According to the invention, the deposition of intramuscular fat can be promoted by adjusting the glycometabolism and lipid metabolism pathways of beef cattle, so that the beef quality and marbling grade are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of feed additives, and in particular relates to a feed additive for improving the marbling grade of beef, and a preparation method and application thereof. Background Art

[0002] The beef cattle industry is an important part of animal husbandry, and beef production ranks among the top in the world all year round. In recent years, due to factors such as high feeding costs, weak market consumption, and the impact of imported beef, beef prices have continued to fall, and the production of conventional beef (red meat) has suffered substantial losses. Some breeding entities have reduced the number of breedings or even withdrawn from the industry, seriously affecting the stability of the industry. However, unlike the production of conventional beef, in the current downturn in the national beef cattle industry, the breeding entities that produce high-quality and high-end beef (marbled meat) are less affected. The main reasons are that the production of high-quality and high-end beef is difficult, the output is low, and the market gap is large. In addition, imported beef is mainly conventional beef, which does not compete with high-quality and high-end beef. This provides an important reference for the transformation and development of the beef cattle industry. Beef quality is closely related to the intramuscular fat (IMF) content. The higher the intramuscular fat content, the higher the marbling grade, and the better the beef quality.

[0003] Intramuscular fat of beef refers to the adipose tissue present in muscle fibers. Its content is positively correlated with the juiciness, tenderness and palatability of beef. Its formation and distribution are regulated by multiple factors such as breed, nutritional level and management. Nutritional regulation has a significant effect on the intramuscular fat content of beef cattle, and plant extracts play an important role in promoting intramuscular fat deposition. Carbohydrate intake is also a key factor affecting fat formation. When beef cattle ingest a large amount of carbohydrates, they will be converted into fat and stored. Therefore, by reasonably controlling the intake of carbohydrates, fat deposition in beef cattle can be effectively regulated. In addition, high-fiber and high-protein feeds such as corn stalks and soybean meal can promote gastrointestinal motility and weight gain in beef cattle, while avoiding overfeeding to prevent beef cattle from being too fat or indigestion. Management measures such as feeding environment can also affect the intramuscular fat content of beef cattle. For example, in cold seasons, beef cattle need more energy to maintain body temperature, so they will store more fat to cope with the cold environment. In addition, reasonable feeding management and feed matching can significantly increase the growth rate and production efficiency of beef cattle, thereby improving meat quality. Therefore, adjusting the nutritional intake and nutritional combination of beef cattle is an important measure to promote intramuscular fat deposition, improve beef quality and thus enhance the marbling grade. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a feed additive for improving the marbling grade of beef, and a preparation method and application thereof, which can promote the deposition of intramuscular fat by regulating the sugar metabolism and lipid metabolism pathways of beef cattle, thereby improving the quality of beef and the marbling grade.

[0005] To achieve the above object, the present invention provides a feed additive for improving the marbling grade of beef, comprising the following components in parts by weight:

[0006] 0.02-0.06 parts of puerarin, 0.05-0.15 parts of seabuckthorn flavonoids, 0.45-0.65 parts of bamboo leaf flavonoids, 0.8-1.2 parts of brewer's yeast (Saccharomyces cerevisiae), 1.5-2.5 parts of rapeseed oil, and 2.6-3.4 parts of olive oil.

[0007] Preferably, the following components are included in parts by weight:

[0008] 0.04 parts of puerarin, 0.1 parts of seabuckthorn flavonoids, 0.55 parts of bamboo leaf flavonoids, 1 part of brewer's yeast, 1.8 parts of rapeseed oil, and 3.2 parts of olive oil.

[0009] Preferably, the Saccharomyces cerevisiae is Saccharomyces cerevisiae CICC1606.

[0010] More preferably, the effective viable count of the Saccharomyces cerevisiae CICC1606 is 1×10 9 ~2×10 9 CFU / g.

[0011] Preferably, the olive oil is extra virgin olive oil.

[0012] The present invention also provides a method for preparing the feed additive, comprising the following steps:

[0013] Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast to obtain a feed additive.

[0014] The present invention also provides application of the feed additive in preparing feed for improving beef quality.

[0015] The present invention also provides application of the feed additive prepared by the preparation method in preparing feed for improving beef quality.

[0016] The present invention also provides application of the feed additive in preparing feed for improving the marbling grade of beef.

[0017] The present invention also provides a feed for improving the marbling grade of beef, comprising the feed additive.

[0018] Compared with the prior art, the present invention has the following advantages and technical effects:

[0019] Puerarin: Regulate lipid metabolism: Puerarin can activate peroxisome proliferator-activated receptor γ (PPARγ), which is a key transcription factor that regulates adipogenesis and lipid metabolism. Activating PPARγ can promote adipocyte differentiation and increase fatty acid synthesis and storage. Antioxidant: It has an antioxidant effect and can reduce the damage of oxidative stress to adipocytes, thereby maintaining the health of adipocytes.

[0020] Seabuckthorn flavonoids: It can regulate the levels of insulin and adiponectin to change the content of very low-density lipoprotein and triglycerides, thereby regulating intramuscular fat deposition. Anti-inflammatory and antioxidant: Seabuckthorn flavonoids have significant anti-inflammatory and antioxidant effects, which can reduce inflammatory reactions and oxidative stress and protect fat cells from damage. Promote adipocyte differentiation: Seabuckthorn flavonoids can reduce the release of inflammatory mediators and promote the normal differentiation and function of adipocytes.

[0021] Bamboo leaf flavonoids: Its antioxidant components include flavonoids, lactones and phenolic acid compounds, among which flavonoid compounds are mainly flavonoid carbon glycosides, including orientin, isoorientin, vitexin and isovitexin. Its action characteristics are that it can block the chain reaction of fat auto-oxidation, has strong anti-free radical activity, and can remove a variety of active oxygen free radicals; it has excellent antioxidant activity, effectively inhibits lipid peroxidation, and has a significant inhibitory effect on the formation of lipid peroxidation product malondialdehyde (MDA); at the same time, it also has a strong antibacterial effect, and has a certain inhibitory effect on typhoid Salmonella, Gram-negative bacilli and positive cocci. Bamboo leaf flavonoids can improve insulin sensitivity, promote glucose uptake and utilization, and indirectly promote fat synthesis.

[0022] Olive oil: Rich in monounsaturated fatty acid - oleic acid, as well as vitamin A, vitamin B, vitamin D, vitamin E, vitamin K and antioxidants. Provide high-quality fatty acids: The monounsaturated fatty acids in olive oil help improve the absorption and utilization efficiency of fatty acids and promote fat deposition. Antioxidant and anti-inflammatory: The polyphenols in olive oil have antioxidant and anti-inflammatory effects, protecting fat cells and promoting their healthy growth.

[0023] Rapeseed oil: Provides essential fatty acids: The unsaturated fatty acids in rapeseed oil provide the necessary raw materials for fat synthesis, increase the supply of fatty acids, and thus promote fat deposition. Regulate fat metabolism: Unsaturated fatty acids can regulate the expression of genes related to fat metabolism, promote the activity of fatty acid synthase, and enhance fat deposition.

[0024] Saccharomyces cerevisiae: Regulates intestinal flora: Saccharomyces cerevisiae can regulate the structure of intestinal flora, increase the number of beneficial bacteria, improve intestinal health, and thus affect the host's nutrient absorption and metabolism. Promote fat metabolism: Saccharomyces cerevisiae can increase the production of short-chain fatty acids (SCFAs) by regulating intestinal flora and host metabolism. These short-chain fatty acids can stimulate adipocyte differentiation and fat synthesis. Improve feed utilization: Saccharomyces cerevisiae can improve the digestibility and utilization of feed, so that more energy and nutrients are used for fat synthesis.

[0025] The present invention improves the supply of saturated fatty acids, regulates fat metabolism, promotes the activity of fatty acid synthase, and enhances fat deposition by externally supplementing rapeseed oil and olive oil. At the same time, puerarin, bamboo leaf flavonoids and seabuckthorn flavonoids are used to jointly regulate the digestion and utilization of nutrients in the body, activate fat synthesis-related genes (such as PPARγ), provide essential fatty acids, improve insulin sensitivity, reduce oxidative stress and inflammation, etc. Combined with saccharomyces cerevisiae to regulate intestinal flora, improve feed utilization, ensure that more energy and nutrients are effectively absorbed and utilized, further promote fat synthesis, and multiple components synergize anti-oxidation and anti-inflammatory, protect fat cells from damage, maintain their healthy state, and thus more effectively carry out fat deposition. These mechanisms work together to help improve the deposition amount and quality of cattle intramuscular fat, and ultimately improve the quality and marbling grade of beef. DETAILED DESCRIPTION

[0026] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0027] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope 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 described 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.

[0028] 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.

[0029] Without departing from the scope or spirit of the present invention, various modifications and variations may be made to the specific embodiments of the present invention description, which will be apparent to those skilled in the art. Other embodiments obtained from the present invention description will be apparent to those skilled in the art. The present invention description and examples are merely exemplary. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art, and the raw materials used are all commercially available commodities.

[0030] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0031] Unless otherwise specified, the "parts" described in the present invention are all based on mass parts.

[0032] Sources of materials used in the present invention: puerarin was purchased from Ruichu Biotechnology; seabuckthorn flavonoids (MF-002582) was purchased from Mufan Biotechnology; bamboo leaf flavonoids was purchased from Xi'an Enpeptideyuan Biotechnology Co., Ltd.; rapeseed oil was purchased from Maclean, and virgin olive oil was purchased from Betis.

[0033] Example 1

[0034] Puerarin 0.04 parts, seabuckthorn flavonoids 0.1 parts, bamboo leaf flavonoids 0.55 parts, brewer's yeast CICC1606 1 parts (effective viable count of 1.5×10 9 CFU / g), 1.8 parts of rapeseed oil, and 3.2 parts of extra virgin olive oil.

[0035] Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and virgin olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast CICC1606 to obtain a feed additive.

[0036] Example 2

[0037] Puerarin 0.02 parts, seabuckthorn flavonoids 0.05 parts, bamboo leaf flavonoids 0.65 parts, brewer's yeast CICC1606 0.8 parts (effective viable count 2×10 9 CFU / g), 1.5 parts of rapeseed oil, and 3.4 parts of extra virgin olive oil.

[0038] Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and virgin olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast CICC1606 to obtain a feed additive.

[0039] Example 3

[0040] Puerarin 0.06 parts, seabuckthorn flavonoids 0.15 parts, bamboo leaf flavonoids 0.45 parts, brewer's yeast CICC1606 1.2 parts (effective viable count 1×109 CFU / g), 2.5 parts of rapeseed oil, and 2.6 parts of extra virgin olive oil.

[0041] Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and virgin olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast CICC1606 to obtain a feed additive.

[0042] Example 4

[0043] Puerarin 0.03 parts, seabuckthorn flavonoids 0.08 parts, bamboo leaf flavonoids 0.6 parts, brewer's yeast CICC1606 0.9 parts (effective viable count 1×10 9 CFU / g), 2 parts of rapeseed oil, and 2.8 parts of extra virgin olive oil.

[0044] Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and virgin olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast CICC1606 to obtain a feed additive.

[0045] Example 5

[0046] Puerarin 0.05 parts, seabuckthorn flavonoids 0.08 parts, bamboo leaf flavonoids 0.5 parts, brewer's yeast CICC1606 1.1 parts (effective viable count 2×10 9 CFU / g), 2.3 parts of rapeseed oil, and 2.6 parts of extra virgin olive oil.

[0047] Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and virgin olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast CICC1606 to obtain a feed additive.

[0048] Comparative Example 1

[0049] Puerarin 0.04 parts, seabuckthorn flavonoids 0.65 parts, brewer's yeast CICC1606 1 parts (effective viable count of 1.5×10 9 CFU / g), 1.8 parts of rapeseed oil, and 3.2 parts of extra virgin olive oil.

[0050] Puerarin and seabuckthorn flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and virgin olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast CICC1606 to obtain a feed additive.

[0051] Comparative Example 2

[0052] Puerarin 0.04 parts, seabuckthorn flavonoids 0.1 parts, bamboo leaf flavonoids 0.55 parts, brewer's yeast CICC12881 parts (effective viable count of 1.5×10 9CFU / g), 1.8 parts of rapeseed oil, and 3.2 parts of extra virgin olive oil.

[0053] Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and virgin olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast CICC1288 to obtain a feed additive.

[0054] Experimental Example 1

[0055] Twenty-four bulls with an initial body weight of 386.62±5.31kg at 9 months of age were divided into four groups, with 6 in each group. The diets fed in the experiment were the same, referring to the "Beef Cattle Feeding Standard" (NY / T815-2004) and the Chinese Feed Composition and Nutritional Value Table (2017, 28th Edition). Water was available freely during the period, and the feeding time was 90 days.

[0056] The composition of the diet: 30.00% silage corn, 10.00% high-quality hay, 11.50% corn straw, 38.00% corn, 5.50% soybean meal, 2.00% wheat bran, 0.50% salt, 0.50% stone powder, 0.50% calcium bicarbonate, 0.50% baking soda, 1.00% premix, totaling 100%. The comprehensive net energy of the diet is 13.05MJ / kg, the crude protein content is 10.87%, the neutral detergent fiber content is 26.06%, the acid detergent fiber content is 18.53%, the calcium content is 0.39%, and the phosphorus content is 0.26%.

[0057] The following premixes are added to each kilogram of diet: V A 50000IU, V D 15000IU, V E 3000IU, Cu 1.3g, Fe4.0g, Mn 3.0g, Zn 6.0g, I 80mg, Se 50mg.

[0058] The control group was fed the above diet twice a day; the experimental group 1 added the feed additive prepared in Example 1 to the above diet at 1% of the diet mass, and the diet was fed twice a day; the experimental group 2 added the feed additive prepared in Comparative Example 1 to the above diet at 1% of the diet mass, and the diet was fed twice a day; the experimental group 3 added the feed additive prepared in Comparative Example 2 to the above diet at 1% of the diet mass, and the diet was fed twice a day.

[0059] After the experiment, three cows were randomly selected from each group and fasted for 24 hours before slaughter. Before slaughter, 15 mL of blood was collected from the jugular vein of the cow, and the serum was collected by centrifugation and stored at -20 ° C. The longissimus dorsi muscle between the 12th and 13th ribs of the left half carcass was collected for meat quality determination.

[0060] 1. Determination of growth performance of control group and experimental group 1.

[0061] The mice were weighed on an empty stomach at 0th, 30th, 60th and 90th day of feeding, and the body weight was recorded.

[0062] Table 1 Growth performance of control group and experimental group 1

[0063] Days Average body weight of experimental group 1 (kg) Average body weight of control group (kg) No. 0d 384.41±3.47 385.02±2.91 30d 438.18±4.15 425.21±5.17 Chapter 60d 489.27±5.28 465.59±7.01 Chapter 90d 532.91±6.62 474.56±7.79

[0064] As shown in Table 1, after the cattle in Experimental Group 1 were fed with the diet supplemented with the feed additive prepared in Example 1, their weight increased significantly and at a relatively faster rate than that of the cattle in the Control Group that were fed with the diet alone.

[0065] 2. Determination of serum indicators in the control group and experimental groups 1 to 3.

[0066] Total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and phospholipids (PL) were determined by colorimetric method (Mindray BS-420 fully automatic biochemical analyzer, Shenzhen Mindray Bio-Medical Electronics Co., Ltd.) using kits produced by Beijing Huaying Biotechnology Research Institute; glucose (Glu) was determined by GOPOD oxidase method (power wave fully automatic microplate reader, Berton Instrument Co., Ltd., USA) using kits produced by Jiangsu Addison Biotechnology Co., Ltd.

[0067] Table 2 Determination of serum glucose and other metabolic indicators in the control group and experimental groups 1 to 3

[0068]

[0069] As shown in Table 2, the glucose concentration in the serum of the bovines in Experimental Group 1, Experimental Group 2 and Experimental Group 3 fed with the diets added with feed additives increased, among which the glucose concentration in Experimental Group 1 increased significantly, which can provide more carbon precursors for intramuscular fat synthesis and promote the synthesis of fatty acids. According to the records in Table 2, the contents of triglycerides, total cholesterol and phospholipids in the serum of the bovines in Experimental Group 1, Experimental Group 2 and Experimental Group 3 fed with the diets added with feed additives increased, and the contents of triglycerides, total cholesterol and phospholipids in Experimental Group 1 increased significantly. Feeding the feed additive prepared in Example 1 promoted the transport of triglycerides and phospholipids in the host, and finally promoted fat deposition.

[0070] 3. Determination of fatty acid composition in the longissimus dorsi muscle of intercostal cattle.

[0071] Weigh an appropriate amount of tissue sample, add 100 μL of internal standard (C17 fatty acid methyl ester, 5.00 mg / mL), then add 2 mL of 5% concentrated sulfuric acid / methanol solution and 300 μL of toluene; seal, mix gently, and extract in a 95°C water bath for 1.5 h; add 2 mL of 0.9% NaCl solution, extract with 1 mL of n-hexane, centrifuge at 5000 rpm for 5 min, separate the layers, and take the supernatant into a sample bottle; perform gas chromatography analysis.

[0072] The working conditions of the gas chromatograph were as follows: FID hydrogen flame ionization detector, DB-FastFAME column, injection port temperature of 250 °C, split ratio of 20:1, detector temperature of 260 °C, initial column temperature of 80 °C, maintained for 0.5 min, programmed temperature increase to 165 °C at 40 °C / min, maintained for 1 min, programmed temperature increase to 230 °C at 4 °C / min, and maintained at this temperature for 6 min.

[0073] Table 3 Fatty acid composition of longissimus dorsi muscle of cattle

[0074]

[0075] As shown in Table 3, the oleic acid content in the longissimus dorsi muscle of the cattle in the experimental group 1 was the highest, and the addition of the feed additive prepared in Example 1 could promote the deposition of fat in the cattle muscle.

[0076] 4. Determination of the quality of the longest intercostal beef back muscle.

[0077] Remove excess fat and fascia from the surface, and refer to the "Determination of Meat Quality of Livestock and Poultry" (NY / T 1333-2007), "Quality Grading of Livestock and Poultry Beef" (GB / T 29392-2022), and "Determination of Meat Tenderness - Shear Force Determination Method" (NY / T 1180-2006) to determine indicators such as meat color, pH value, shear force, drip loss, water loss rate, cooked meat rate, and marbling (grade).

[0078] Meat color: visually evaluate the muscle samples under natural light indoors using a colorimetric plate, with 1 point representing grayish white, 2 points representing slightly reddish, 3 points representing bright red, 4 points representing slightly dark red, and 5 points representing dark red.

[0079] Marble pattern rating: Marble pattern rating is carried out against the colorimetric plate and is divided into 5 levels, namely level 1 (almost none), level 2 (a little), level 3 (relatively abundant), level 4 (abundant), and level 5 (extremely abundant).

[0080] pH value: insert the electrode of the pH meter into the muscle 2 cm deep, measure the pH value of the muscle samples 45 minutes and 24 hours after slaughter (stored at 4°C), record the values, and take the average value of the three measurements.

[0081] Shear force: Heat the meat sample until the core temperature reaches 70°C, then cool it to 0-4°C, take a sample with a circular sampler, and measure the shear force using a muscle tenderizer.

[0082] Drip loss = (weight of meat sample before hanging - weight of meat sample after hanging) / weight of meat sample before hanging × 100%;

[0083] Water loss rate = (weight of meat sample before pressure-weight of meat sample after pressure) / weight of meat sample before pressure × 100%;

[0084] Cooked meat rate = cooked meat sample weight / fresh meat sample weight × 100%.

[0085] Table 4 Determination of the quality of the longest muscle of the intercostal beef back

[0086] Group Control group Experimental Group 1 Experimental Group 2 Experimental Group 3 Flesh color 3 3 3 3 pH45min value 6.25 6.44 6.30 6.31 pH24h value 5.69 5.88 5.71 5.72 Shear force / N 43.12 41.53 42.78 42.66 Drip loss / % 2.18 1.87 2.04 2.08 Water loss rate / % 22.03 20.01 21.16 21.34 Cooked meat rate / % 54.98 57.12 55.36 55.33 Marbling Grade 2.67 4.33 3.33 3.33

[0087] As shown in Table 4, the marbling pattern of the longissimus intercostal muscle of experimental group 1 was significantly better than that of the other groups.

[0088] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A feed additive for improving the marbling grade of beef, characterized in that: The composition comprises the following components in parts by weight: 0.02-0.06 parts of puerarin, 0.05-0.15 parts of seabuckthorn flavonoids, 0.45-0.65 parts of bamboo leaf flavonoids, 0.8-1.2 parts of brewer's yeast (Saccharomyces cerevisiae), 1.5-2.5 parts of rapeseed oil, and 2.6-3.4 parts of olive oil.

2. The feed additive according to claim 1, characterized in that: The composition comprises the following components in parts by weight: 0.04 parts of puerarin, 0.1 parts of seabuckthorn flavonoids, 0.55 parts of bamboo leaf flavonoids, 1 part of brewer's yeast, 1.8 parts of rapeseed oil, and 3.2 parts of olive oil.

3. The feed additive according to claim 1 or 2, characterized in that: The brewer's yeast is brewer's yeast CICC1606.

4. The feed additive according to claim 3, characterized in that: The effective viable count of Saccharomyces cerevisiae CICC1606 is 1×10 9 ~2×10 9 CFU / g.

5. The feed additive according to claim 1 or 2, characterized in that: The olive oil is extra virgin olive oil.

6. The method for preparing the feed additive according to any one of claims 1 to 5, characterized in that: The following steps are involved: Puerarin, seabuckthorn flavonoids and bamboo leaf flavonoids are mixed to obtain a primary mixture, and then the primary mixture is mixed with rapeseed oil and olive oil to obtain a premix, and the premix is ​​mixed with brewer's yeast to obtain a feed additive.

7. Use of the feed additive according to any one of claims 1 to 5 in preparing feed for improving beef quality.

8. Use of the feed additive prepared by the preparation method as claimed in claim 6 in preparing feed for improving beef quality.

9. Use of the feed additive according to any one of claims 1 to 5 in preparing feed for improving the marbling grade of beef.

10. A feed for improving the marbling grade of beef, characterized in that: The feed additive comprises the feed additive as claimed in any one of claims 1 to 5.

Images