Branched chain fatty acid preparation for improving growth performance of calves and preparation method of branched chain fatty acid preparation

Abstract

The invention belongs to the technical field of biological medicine, and particularly relates to a branched chain fatty acid preparation for improving growth performance of calves and a preparation method thereof. The branched-chain fatty acid preparation for improving the growth performance of the calves comprises the following components in parts by weight: 1-5 parts of a procyanidine derivative, 3-10 parts of a mulberry leaf extract, 3-10 parts of branched-chain fatty acid and 0.3-0.8 part of a trace element compound. The prepared branched chain fatty acid preparation for improving the growth performance of the calves can regulate rumen fermentation and reduce the discharge amount of methane and the content of skatole, so that the bloating symptom of animals is effectively reduced, the odor of excrement is reduced, a better growth environment is provided for the animals, and the growth and development of the animals are promoted.

Description

Technical Field

[0001] The present invention belongs to the technical field of biomedicine, and particularly relates to a branched-chain fatty acid preparation for improving the growth performance of calves and a preparation method thereof. Background Art

[0002] When calves are born, the rumen has not yet developed, lacking functional microbial communities and ciliates. With the introduction of solid feed, the rumen needs to adapt to the new nutritional pattern through structural development (such as the formation of papillary projections) and functional improvement (such as the enhancement of volatile fatty acid metabolism ability). However, the rapid increase in starch and fiber in the diet during the weaning period often leads to fluctuations in rumen pH value and imbalances in the microbial flora, thereby causing flatulence.

[0003] Branched-chain fatty acids (BCFAs) are a class of saturated fatty acids with a special branched-chain structure, having one or more branched chains (mainly methyl groups) on their carbon skeletons, and are divided into two categories: single-branched chains and multi-branched chains. Due to their branched-chain structure, BCFAs have unique physical and chemical properties such as low freezing point, high thermal stability, and oxidation stability, and their digestion and metabolism pathways in the body are different from those of straight-chain fatty acids, having special physiological regulatory functions. In view of the special physiological stage of calves during the weaning period, the metabolic characteristics and functional properties of BCFAs may provide new ideas for their nutritional regulation.

[0004] After calves are weaned, the rumen develops rapidly, and the absorption of short-chain fatty acids becomes the main energy source. However, at this time, the feed intake of forage increases, and when the rumen microorganisms of calves decompose cellulose, volatile fatty acids (such as acetic acid and propionic acid) and methane are produced, which easily leads to flatulence. In addition, the odor pollution generated during the growth of animals also severely restricts the development of livestock and poultry farming. The growth and absorption of these odor components mainly occur in the rumen, mainly due to the unutilized nutrients in the animal intestine and the metabolic products generated by microbial fermentation. In ruminant farming, reducing the content of odor components is of great significance for improving the ranch environment and the growth and development of cattle.

[0005] Therefore, there is an urgent need to develop a preparation of branched-chain fatty acids for improving the growth performance of calves, regulating rumen fermentation, reducing the methane emissions of calves and improving the growth environment, and promoting the growth and development of calves. Summary of the Invention

[0006] In order to overcome the deficiencies of the prior art, one of the purposes of the present invention is to provide a branched-chain fatty acid preparation for improving the growth performance of calves.

[0007] One of the purposes of the present invention is achieved by adopting the following technical solution: The present invention provides a branched-chain fatty acid preparation for improving the growth performance of calves, which comprises the following components in parts by weight: 1-5 parts of proanthocyanidin derivatives, 3-10 parts of mulberry leaf extract, 3-10 parts of branched-chain fatty acids, and 0.3-0.8 parts of trace element compounds; the structure of the proanthocyanidin derivatives is: 。

[0008] Among them, the flavonoid compounds (such as rutin and quercetin) and polyphenols in the mulberry leaf extract added in the present invention have broad-spectrum antibacterial activity, can inhibit the excessive proliferation of gas-producing bacteria such as methanogens and hydrogen sulfide-producing bacteria in the rumen, and reduce the generation of methane.

[0009] Furthermore, the preparation process of the proanthocyanidin derivatives comprises the following steps: (1) Ethyl (E)-4-hydroxy-2-butenoate, 7-chloroisoquinoline and potassium carbonate are added to N,N-dimethylformamide, heated for reaction, and purified to obtain intermediate 1; (2) Prepare an anhydrous tetrahydrofuran solution of intermediate 1, add the anhydrous tetrahydrofuran solution of intermediate 1 to the anhydrous tetrahydrofuran solution of lithium aluminum hydride for reaction to obtain intermediate 2; (3) Add proanthocyanidins, butyric acid and triphenyl phosphate to anhydrous tetrahydrofuran, add diisopropyl azodicarboxylate, and stir for reaction to obtain a proanthocyanidin intermediate; (4) React the proanthocyanidin intermediate, intermediate 2, and silver oxide in a mixed solution prepared from anhydrous toluene and anhydrous acetone in a volume ratio of 2:1 to obtain proanthocyanidin derivatives.

[0010] Furthermore, in step (1), the molar ratio of ethyl (E)-4-hydroxy-2-butenoate, 7-chloroisoquinoline and potassium carbonate is 1:(1.2-1.5):(1.5-1.8); the concentration of ethyl (E)-4-hydroxy-2-butenoate in N,N-dimethylformamide is 0.4 mol / L; the temperature of the heating reaction is 50-80 °C, and the time is 10-16 h.

[0011] Furthermore, in step (2), the molar ratio of intermediate 1 and lithium aluminum hydride is 1:(1.5-2), the concentration of the anhydrous tetrahydrofuran solution of intermediate 1 is 0.5 mol / L, and the concentration of the anhydrous tetrahydrofuran solution of lithium aluminum hydride is 0.4 mol / L; the temperature of the reaction system when the anhydrous tetrahydrofuran solution of intermediate 1 is added to the anhydrous tetrahydrofuran solution of lithium aluminum hydride is 0 °C, the reaction temperature is room temperature, and the time is 1-2 h.

[0012] Further, in step (3), the molar ratio of the procyanidin, butyric acid, triphenyl phosphate, and diisopropyl azodicarboxylate is 1:(2 - 2.5):(2 - 2.5):(2 - 2.5), and the reaction time is 16 - 24 h; the dosage ratio of the procyanidin to anhydrous tetrahydrofuran is 1 mmol:8 mL.

[0013] Further, the chemical structural formula of the procyanidin is .

[0014] Further, in step (4), the molar ratio of the procyanidin intermediate, intermediate 2, and silver oxide is 1:(2.2 - 3):(2.8 - 3.5), the reaction temperature is 70 - 85 °C, and the time is 10 - 16 h; the dosage ratio of the procyanidin intermediate to the mixed solution is 1 mmol:7.5 mL.

[0015] Further, the preparation process of the mulberry leaf extract is as follows: Wash the mulberry leaves, dry them at 55 °C for 5 h, crush them and pass through a 40 - mesh sieve to obtain mulberry leaf powder. Add the mulberry leaf powder to a 60 v / v% ethanol solution, and the dosage ratio of the mulberry leaf powder to the ethanol solution is 1 g:30 mL. Ultrasonically extract at 50 - 60 °C for 30 - 60 min, centrifuge at 4000 - 5000 rpm for 5 - 10 min, take the supernatant, and freeze - dry it to obtain the mulberry leaf extract.

[0016] Further, the branched - chain fatty acid is any one of 12 - methyltridecanoic acid, 13 - methyltetradecanoic acid, and 14 - methylpentadecanoic acid; the trace element compound is any one of iron glycinate, sodium selenite, and zinc glycinate.

[0017] The second object of the invention is to provide a preparation method of a branched - chain fatty acid preparation for improving the growth performance of calves.

[0018] The second object of the present invention is achieved by the following technical solution: The present invention provides the above - mentioned preparation method of the branched - chain fatty acid preparation for improving the growth performance of calves, including the following steps: Mix the formula - amount of mulberry leaf extract, procyanidin derivative, branched - chain fatty acid, and trace element compound evenly to obtain the branched - chain fatty acid preparation for improving the growth performance of calves.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention provides a branched - chain fatty acid preparation for improving the growth performance of calves. By scientifically proportioning the mulberry leaf extract, procyanidin derivative, branched - chain fatty acid, and trace element, a branched - chain fatty acid preparation for improving the growth performance of calves is prepared, which can regulate rumen fermentation, reduce the methane emission and the content of skatole, thereby effectively reducing the occurrence of bloat symptoms in animals, reducing the fecal odor, and better promoting the growth and development of calves.

[0020] 2. The present invention introduces proanthocyanidin derivatives into the preparation. By introducing a nitrogen-containing heterocycle (similar in structure to the tryptophan group), the proanthocyanidin derivatives can competitively bind to tryptophan decarboxylase with tryptophan, thus occupying the active site of tryptophan decarboxylase and preventing tryptophan from binding to tryptophan decarboxylase. As a result, the tryptophan metabolism rate is reduced, and the conversion of tryptophan into indole metabolites (such as 3-methylindole) is decreased, providing a good growth environment for calves. In addition, the butyrate group introduced into the proanthocyanidin structure in the present invention has the effects of promoting animal growth and improving intestinal health.

[0021] 3. The present invention provides a method for preparing the above-mentioned branched-chain fatty acid preparation for improving the growth performance of calves. This method is simple to operate and is conducive to industrial production. Detailed implementation manners

[0022] Next, in combination with the detailed implementation manners, the present invention will be further described. It should be noted that, on the premise of no conflict, the following-described embodiments or technical features can be arbitrarily combined with each other to form new embodiments. The specific conditions not specified in the embodiments are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used, unless otherwise specified, are all conventional products obtained through commercial channels.

[0023] (I) Embodiments Example 1 This example provides a branched-chain fatty acid preparation for improving the growth performance of calves, which comprises the following components in parts by weight: 3 parts of proanthocyanidin derivatives, 7 parts of mulberry leaf extract, 6 parts of 12-methyltridecanoic acid, and 0.5 part of ferrous glycinate; the structure of the proanthocyanidin derivatives is: .

[0024] Among them, the preparation process of the proanthocyanidin derivatives includes the following steps: (1) Ethyl (E)-4-hydroxy-2-butenoate (CAS: 10080-68-9), 7-chloroisoquinoline, and potassium carbonate were added to N,N-dimethylformamide in a molar ratio of 1:1.4:1.6. The concentration of ethyl (E)-4-hydroxy-2-butenoate in N,N-dimethylformamide was 0.4 mol / L. After heating to 65 °C, the reaction was carried out for 14 h; the reaction solution was cooled to room temperature, poured into water, and the aqueous phase was extracted with ethyl acetate. Then, the ethyl acetate phase was washed successively with saturated brine and water, and the organic phase was dried with anhydrous sodium sulfate, filtered, concentrated, and purified by silica gel column chromatography to obtain intermediate 1 (yield: 95%); 1 HNMR (C 15H 15 NO3, DMSO-d6, 300 MHz): δ 9.19 (s, 1H), 8.43 (d, 1H), 7.58 - 7.50 (m, 3H), 7.12 - 7.07 (m, 2H), 6.06 (d, 1H), 4.67 (d, 2H), 4.06 (q, 2H), 1.22 (t, 3H). ESI-MS(m / z): 258.11[M + H] + 。

[0025] (2)Under a nitrogen atmosphere, lithium aluminum hydride was added to anhydrous tetrahydrofuran. After stirring evenly, a lithium aluminum hydride solution with a concentration of 0.4 mol / L was prepared. It was cooled to 0 °C, and then Intermediate 1 was dissolved in anhydrous tetrahydrofuran to prepare an Intermediate 1 solution with a concentration of 0.5 mol / L. Then, the Intermediate 1 solution was added dropwise to the lithium aluminum hydride solution. The molar ratio of Intermediate 1 to lithium aluminum hydride was 1:1.7. After the addition was completed, the temperature was gradually raised to room temperature, and the reaction was carried out at room temperature for 1.5 h; the reaction was quenched by adding water, and the mixture was extracted with ethyl acetate. The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated to obtain Intermediate 2 (yield: 81.3%); 1 HNMR (C 13 H 13 NO2, DMSO-d6, 300 MHz): δ 9.19 (s, 1H), 8.43 (d, 1H), 7.58 - 7.50 (m, 3H), 7.12 (s, 1H), 5.89 - 5.87 (m, 2H), 5.08 (s, 1H), 4.69 - 4.67 (m, 2H), 4.19 - 4.17 (m, 2H). ESI-MS(m / z): 216.10[M + H] + 。

[0026] (3)Procyanidins, butyric acid, triphenyl phosphate, and diisopropyl azodicarboxylate were weighed respectively according to a molar ratio of 1:2.2:2.2:2.2. Then, under a nitrogen atmosphere, procyanidins, butyric acid, and triphenyl phosphate (TPP) were added to anhydrous tetrahydrofuran. The dosage ratio of procyanidins to anhydrous tetrahydrofuran was 1 mmol:8 mL; then, diisopropyl azodicarboxylate (DIAD) was added at 0 °C, and the mixture was stirred at room temperature for 20 h; the crude reaction mixture was purified by column chromatography to obtain (yield: 72%). Procyanidin intermediate 1 HNMR (C 38 H 38 O 15, DMSO-d6, 300 MHz): δ 10.30 (s, 2H), 9.70 (s, 2H), 9.48 (s, 4H), 6.82 - 6.64 (m, 7H), 6.45 (d, 1H), 5.95 - 5.92 (m, 2H), 5.08 (d, 1H), 4.58 (q, 3H), 2.79 - 2.56 (m, 2H), 2.35 (t, 4H), 1.69 - 1.67 (m, 4H), 0.99 (t, 6H). ESI-MS (m / z): 734.22[M].

[0027] (4) At room temperature, the proanthocyanidin intermediate, intermediate 2, and silver oxide were added successively in a molar ratio of 1:2.5:3 to a mixed solution of anhydrous toluene and anhydrous acetone (obtained by mixing anhydrous toluene and anhydrous acetone in a volume ratio of 2:1), where the dosage ratio of the proanthocyanidin intermediate to the above mixed solution was 1 mmol:7.5 mL; stirred evenly at room temperature, heated to 80 °C and reacted for 14 h; after cooling the reaction solution to room temperature, filtered, concentrated the filtrate and purified it by silica gel column chromatography (the volume ratio of dichloromethane to methanol was 15:1) to obtain the proanthocyanidin derivative (yield: 32.4%). Proanthocyanidin derivative 1 HNMR (C 64 H 60 N2O 19 , DMSO-d6, 300 MHz): δ 10.30 (s, 2H), 9.70 (s, 2H), 9.19 (s, 2H), 8.43 (d, 2H), 7.58 - 7.50 (m, 6H), 7.13 - 7.10 (m, 4H), 6.97 (d, 2H), 6.87 (d, 2H), 6.70 (d, 1H), 6.45 (d, 1H), 5.95 - 5.88 (m, 4H), 5.08 (d, 1H), 4.62 - 4.58 (m, 3H), 4.42 - 4.20 (m, 4H), 4.10 (m, 2H), 4.00 (s, 2H), 3.80 - 3.74 (m, 4H), 2.79 - 2.56 (m, 2H), 2.35 (t, 4H), 1.69 - 1.67 (m, 4H), 0.99 (t, 6H). ESI-MS (m / z): 1160.40[M].

[0028] The preparation process of the above-mentioned mulberry leaf extract is as follows: Take fresh mulberry leaves, wash and dry them, then crush them through a 40-mesh sieve to obtain mulberry leaf powder. Add the mulberry leaf powder to an ethanol solution with a volume fraction of 60%, where the dosage ratio of mulberry leaf powder to ethanol solution is 1 g: 30 mL. Perform ultrasonic extraction at 60 °C for 60 min, centrifuge the extract at 4500 rpm for 10 min, take the supernatant, concentrate it, and then perform freeze-drying to obtain the mulberry leaf extract.

[0029] This example also provides a preparation method of the above-mentioned branched-chain fatty acid preparation for improving the growth performance of calves, including the following steps: Put the formulated amounts of mulberry leaf extract, proanthocyanidin derivative, 12-methyltridecanoic acid, and ferrous glycinate into a mixer and mix them to obtain the branched-chain fatty acid preparation for improving the growth performance of calves.

[0030] Example 2 This example provides a branched-chain fatty acid preparation for improving the growth performance of calves, including the following components in parts by weight: 1 part of proanthocyanidin derivative, 3 parts of mulberry leaf extract, 3 parts of 13-methyltetradecanoic acid, and 0.3 part of sodium selenite; the structure of the proanthocyanidin derivative is: 。

[0031] Among them, the preparation process of the proanthocyanidin derivative includes the following steps: (1) Add ethyl (E)-4-hydroxy-2-butenoate, 7-chloroisoquinoline, and potassium carbonate to N,N-dimethylformamide according to a molar ratio of 1: 1.2: 1.5, where the concentration of ethyl (E)-4-hydroxy-2-butenoate in N,N-dimethylformamide is 0.4 mol / L. After heating to 50 °C, react for 16 h; cool the reaction solution to room temperature, pour the reaction solution into water, and extract the aqueous phase with ethyl acetate. Then, wash the ethyl acetate phase successively with saturated brine and water, dry the organic phase with anhydrous sodium sulfate, filter and concentrate it, and then purify it by silica gel column chromatography to obtain Intermediate 1 (yield: 93.4%); 1 The results of HNMR and ESI-MS (m / z) are the same as those in Example 1.

[0032] (2) Under a nitrogen atmosphere, add lithium aluminum hydride to anhydrous tetrahydrofuran, stir evenly to obtain a lithium aluminum hydride solution with a concentration of 0.4 mol / L, cool it to 0 °C, then dissolve Intermediate 1 in anhydrous tetrahydrofuran to obtain an Intermediate 1 solution with a concentration of 0.5 mol / L, and then gradually add it dropwise to the lithium aluminum hydride solution. The molar ratio of Intermediate 1 to lithium aluminum hydride is 1: 1.5. After adding the materials, gradually warm up to room temperature and react at room temperature for 1 h; quench the reaction with water, then extract the mixture with ethyl acetate, combine the organic phases, wash them with saturated brine, dry them with anhydrous sodium sulfate, and concentrate to obtain Intermediate 2 (yield: 80.1%); 1The results of HNMR and ESI-MS (m / z) are the same as those in Example 1.

[0033] (3) Weigh procyanidins, butyric acid, triphenyl phosphate, and diisopropyl azodicarboxylate according to a molar ratio of 1:2:2:2 respectively. Then, under a nitrogen atmosphere, add procyanidins, butyric acid, and triphenyl phosphate to anhydrous tetrahydrofuran, where the dosage ratio of procyanidins to anhydrous tetrahydrofuran is 1 mmol:8 mL. Then add diisopropyl azodicarboxylate at 0 °C and stir at room temperature for 16 h. Purify the crude reaction mixture by column chromatography to obtain the procyanidin intermediate (yield: 70.6%). Procyanidin intermediate 1 The results of HNMR and ESI-MS (m / z) are the same as those in Example 1.

[0034] (4) At room temperature, add the procyanidin intermediate, Intermediate 2, and silver oxide to a mixed solution of anhydrous toluene and anhydrous acetone (obtained by mixing anhydrous toluene and anhydrous acetone in a volume ratio of 2:1) in sequence according to a molar ratio of 1:2.2:2.8, where the dosage ratio of the procyanidin intermediate to the above mixed solution is 1 mmol:7.5 mL. Stir evenly at room temperature, heat up to 70 °C and react for 16 h. After cooling the reaction solution to room temperature, filter it. Concentrate the filtrate and purify it by silica gel column chromatography (the volume ratio of dichloromethane to methanol is 15:1) to obtain the procyanidin derivative (yield: 30.5%). Procyanidin derivative 1 The results of HNMR and ESI-MS (m / z) are the same as those in Example 1.

[0035] The preparation process of the above-mentioned mulberry leaf extract is the same as that in Example 1.

[0036] This example also provides a preparation method of the above-mentioned branched-chain fatty acid preparation for improving the growth performance of calves, including the following steps: Put the formulated amounts of mulberry leaf extract, procyanidin derivative, 13-methyltetradecanoic acid, and sodium selenite into a mixer and mix them to obtain the branched-chain fatty acid preparation for improving the growth performance of calves.

[0037] Example 3 This example provides a branched-chain fatty acid preparation for improving the growth performance of calves, including the following components in parts by weight: 5 parts of procyanidin derivative, 10 parts of mulberry leaf extract, 10 parts of 14-methylpentadecanoic acid, and 0.8 part of zinc glycinate; the structure of the procyanidin derivative is: .

[0038] Among them, the preparation process of the procyanidin derivative includes the following steps: (1) Ethyl (E)-4-hydroxy-2-butenoate, 7-chloroisoquinoline and potassium carbonate were added to N,N-dimethylformamide in a molar ratio of 1:1.5:1.8. The concentration of ethyl (E)-4-hydroxy-2-butenoate in N,N-dimethylformamide was 0.4 mol / L. After heating to 80 °C, the reaction was carried out for 10 h. The reaction solution was cooled to room temperature, poured into water, and the aqueous phase was extracted with ethyl acetate. Then the ethyl acetate phase was washed successively with saturated brine and water, and the organic phase was dried over anhydrous sodium sulfate, filtered, concentrated and purified by silica gel column chromatography to obtain Intermediate 1 (yield: 94.6%); 1 The results of HNMR and ESI-MS (m / z) were the same as those in Example 1.

[0039] (2) Under a nitrogen atmosphere, lithium aluminum hydride was added to anhydrous tetrahydrofuran, and after stirring evenly, a lithium aluminum hydride solution with a concentration of 0.4 mol / L was prepared. It was cooled to 0 °C, and then Intermediate 1 was dissolved in anhydrous tetrahydrofuran to prepare an Intermediate 1 solution with a concentration of 0.5 mol / L, which was then added dropwise to the lithium aluminum hydride solution. The molar ratio of Intermediate 1 to lithium aluminum hydride was 1:2. After the addition was completed, the temperature was gradually raised to room temperature, and the reaction was carried out at room temperature for 2 h. The reaction was quenched by adding water, and the mixture was extracted with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated to obtain Intermediate 2 (yield: 81.2%); 1 The results of HNMR and ESI-MS (m / z) were the same as those in Example 1.

[0040] (3) Procyanidin, butyric acid, triphenyl phosphate and diisopropyl azodicarboxylate were weighed respectively in a molar ratio of 1:2.5:2.5:2.5. Then, under a nitrogen atmosphere, procyanidin, butyric acid and triphenyl phosphate were added to anhydrous tetrahydrofuran. The dosage ratio of procyanidin to anhydrous tetrahydrofuran was 1 mmol: 8 mL. Diisopropyl azodicarboxylate (DIAD) was added at 0 °C, and the mixture was stirred at room temperature for 24 h. The crude reaction mixture was purified by column chromatography to obtain the procyanidin intermediate (yield: 71.3%). 1 The results of HNMR and ESI-MS (m / z) were the same as those in Example 1.

[0041] (4) At room temperature, the proanthocyanidin intermediate, intermediate 2, and silver oxide were successively added to a mixed solution of anhydrous toluene and anhydrous acetone (obtained by mixing anhydrous toluene and anhydrous acetone in a volume ratio of 2:1) according to a molar ratio of 1:3:3.5. The dosage ratio of the proanthocyanidin intermediate to the above mixed solution was 1 mmol:7.5 mL. It was stirred evenly at room temperature, heated to 85 °C and reacted for 10 h. After cooling the reaction solution to room temperature, it was filtered. The filtrate was concentrated and purified by silica gel column chromatography (the volume ratio of dichloromethane to methanol was 15:1) to obtain the proanthocyanidin derivative (yield: 31.2%). The proanthocyanidin derivative 1 The results of HNMR and ESI-MS (m / z) were the same as those in Example 1.

[0042] The preparation process of the above-mentioned mulberry leaf extract was the same as that in Example 1.

[0043] This example also provides a preparation method of the branched-chain fatty acid preparation for improving the growth performance of calves, including the following steps: Loading the formula amount of mulberry leaf extract, proanthocyanidin derivative, 14-methylpentadecanoic acid, and zinc glycinate into a mixer and mixing to obtain the branched-chain fatty acid preparation for improving the growth performance of calves.

[0044] (II) Comparative Example Comparative Example 1 This Comparative Example 1 was basically the same as Example 1, the difference being that the proanthocyanidin derivative was replaced with an equal amount of proanthocyanidin.

[0045] (III) Test Example Test Example 1 Before the start of the feeding test, the feed troughs and water troughs in the cattle pen were thoroughly disinfected. Three-month-old calves were selected as test animals. Subsequently, the above calves were randomly divided into 4 groups, with 7 calves in each group, which were respectively recorded as: Example 1 group, Example 2 group, Example 3 group, and Comparative Example 1 group.

[0046] Example 1 group: Basal diet and the straight-chain fatty acid preparation obtained in Example 1 accounting for 1% of the basal diet quality; Example 2 group: Basal diet and the straight-chain fatty acid preparation obtained in Example 2 accounting for 1% of the basal diet quality; Example 3 group: Basal diet and the straight-chain fatty acid preparation obtained in Example 3 accounting for 1% of the basal diet quality; Comparative Example 1 group: Basal diet and the straight-chain fatty acid preparation obtained in Comparative Example 1 accounting for 1% of the basal diet quality; The basal diet comprises the following components in weight percentage: 56.5% of corn, 23.15% of soybean meal, 10.5% of wheat bran, 6.5% of corn dried distillers grains and solubles, 2.3% of limestone powder, 0.55% of dicalcium phosphate, and 0.5% of table salt. Before each feeding, the basal diet is uniformly mixed with the corresponding linear fatty acid preparation in advance, and fed 2 times a day according to the above dosage. During this period, all groups are allowed free access to food and water to ensure that the pens are clean and hygienic.

[0047] (1) Before the formal start of the experiment (day 0) and after the end of the experiment (day 90), all the experimental cattle are weighed, and the average daily gain of each cattle is calculated according to the formula. Average daily gain = (final measured weight - initial weight) / number of experimental days. The experimental results are recorded in Table 1.

[0048] Table 1 In the fattening production of cattle, the daily gain is an important indicator reflecting the fattening effect of Chinese Holstein female calves. From the experimental results in Table 1, it can be seen that the weights of the calves in Examples 1 - 3 are significantly higher than those in Comparative Example 1 (replacing the proanthocyanidin derivative with an equal amount of proanthocyanidin), indicating that the branched-chain fatty acid preparation prepared by the present invention has certain advantages in promoting animal growth.

[0049] (2) Three days before the end of the experimental period, rumen fluid is collected through the oral cavity with a sterilized oral catheter before morning feeding every day. After filtering with four layers of sterile gauze, the content of volatile fatty acids (including acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid) in the collected rumen fluid is measured by a gas chromatograph, and the average value of 3 days is used as the final collection result. The experimental results are recorded in Table 2.

[0050] Table 2 The rumen is an organ unique to ruminants, and its rumen fermentation parameters are closely related to the energy utilization of ruminants. The production of volatile fatty acids in rumen fluid is often used to evaluate rumen fermentation. As can be seen from Table 2, the concentration of volatile fatty acids in Examples 1 - 3 of the present invention is higher than that in Comparative Example 1 group. This result indicates that rumen fermentation is active, enabling animals to have a higher utilization efficiency of feed, generating more energy for calf growth through fermentation, and thus contributing to an increase in calf weight.

[0051] (3) On the last day of the experimental period (day 90), the methane emissions of each group of calves are measured using the American Sable open-circuit cyclic calorimetry system, and the results are shown in Table 3.

[0052] Table 3 As can be seen from the data in Table 3, the methane emissions in Examples 1-3 of the present invention can be as low as 52.36 at the lowest, which is much lower than the methane emissions in Comparative Example 1. The above results indicate that the addition of the straight-chain fatty acid preparation in the present invention effectively reduces the methane emissions. The reduction of methane emissions means that more energy is used for the growth of cattle, improving the feed conversion rate, and thus promoting the growth and development of cattle.

[0053] (4)On the last day of the experiment (the 90th day), the feces of each cow in the above groups were collected, and then the content of skatole (3-methylindole) in the cow dung was determined by high performance liquid chromatography (HPLC method). The test results are recorded in Table 4.

[0054] Table 4 As can be seen from Table 4, the skatole content in Examples 1-3 of the present invention is much lower than that in the group of Comparative Example 1. This result shows that the added proanthocyanidin derivative in the branched-chain fatty acid preparation in the present application plays an important role. This is because after the modification of proanthocyanidins, they contain a nitrogen heterocycle similar to the tryptophan group, which can competitively bind to tryptophan decarboxylase with tryptophan, reducing the metabolic rate of tryptophan, and thus reducing the skatole content, providing a good growth environment for calves.

[0055] The above embodiments are only the preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention belong to the scope of protection required by the present invention.

Claims

1. A branched-chain fatty acid preparation for improving the growth performance of calves, characterized in that, Comprising the following components in parts by weight: 1-5 parts of proanthocyanidin derivative, 3-10 parts of mulberry leaf extract, 3-10 parts of branched-chain fatty acid, 0.3-0.8 part of trace element compound; the chemical structural formula of the proanthocyanidin derivative is: .

2. The branched-chain fatty acid preparation for improving the growth performance of calves according to claim 1, characterized in that, The preparation process of the proanthocyanidin derivative includes the following steps: (1) Ethyl (E)-4-hydroxy-2-butenoate, 7-chloroisoquinoline, and potassium carbonate are added to N,N-dimethylformamide, and heated for reaction. After purification, intermediate 1 is obtained; (2) Prepare an anhydrous tetrahydrofuran solution of intermediate 1, and add the anhydrous tetrahydrofuran solution of intermediate 1 to the anhydrous tetrahydrofuran solution of lithium aluminum hydride for reaction to obtain intermediate 2; (3) Proanthocyanidin, butyric acid, and triphenyl phosphate are added to anhydrous tetrahydrofuran, and diisopropyl azodicarboxylate is added, followed by stirring for reaction to obtain a proanthocyanidin intermediate; (4) The proanthocyanidin intermediate, intermediate 2, and silver oxide are added to a mixed solution prepared from anhydrous toluene and anhydrous acetone in a volume ratio of 2:1 for reaction to obtain the proanthocyanidin derivative.

3. The branched-chain fatty acid preparation for improving the growth performance of calves according to claim 2, wherein In step (1), the molar ratio of ethyl (E)-4-hydroxy-2-butenoate, 7-chloroisoquinoline, and potassium carbonate is 1:(1.2 - 1.5):(1.5 - 1.8); the concentration of ethyl (E)-4-hydroxy-2-butenoate in N,N-dimethylformamide is 0.4 mol / L; the temperature of the heating reaction is 50 - 80 °C, and the time is 10 - 16 h.

4. The branched-chain fatty acid preparation for improving the growth performance of calves according to claim 2, characterized in that, In step (2), the molar ratio of intermediate 1 and lithium aluminum hydride is 1:(1.5 - 2), the concentration of the anhydrous tetrahydrofuran solution of intermediate 1 is 0.5 mol / L, and the concentration of the anhydrous tetrahydrofuran solution of lithium aluminum hydride is 0.4 mol / L; when the anhydrous tetrahydrofuran solution of intermediate 1 is added to the anhydrous tetrahydrofuran solution of lithium aluminum hydride, the temperature of the reaction system is 0 °C, the reaction temperature is room temperature, and the time is 1 - 2 h.

5. The branched-chain fatty acid preparation for improving the growth performance of calves according to claim 2, wherein In step (3), the molar ratio of proanthocyanidin, butyric acid, triphenyl phosphate, and diisopropyl azodicarboxylate is 1:(2 - 2.5):(2 - 2.5):(2 - 2.5), the reaction time is 16 - 24 h; the dosage ratio of proanthocyanidin and anhydrous tetrahydrofuran is 1 mmol:8 mL.

6. The branched-chain fatty acid preparation for improving the growth performance of calves according to claim 2, wherein In step (4), the molar ratio of the proanthocyanidin intermediate, intermediate 2, and silver oxide is 1:(2.2 - 3):(2.8 - 3.5), the reaction temperature is 70 - 85 °C, and the time is 10 - 16 h; the dosage ratio of the proanthocyanidin intermediate and the mixed solution is 1 mmol:7.5 mL.

7. The branched-chain fatty acid preparation for improving the growth performance of calves according to claim 1, wherein The preparation process of the mulberry leaf extract is as follows: Wash the mulberry leaves, dry them at 55 °C for 5 h, crush them and pass through a 40-mesh sieve to obtain mulberry leaf powder. Add the mulberry leaf powder to a 60 v / v% ethanol solution, and the dosage ratio of the mulberry leaf powder and the ethanol solution is 1 g:30 mL. Perform ultrasonic extraction at 50 - 60 °C for 30 - 60 min, centrifuge at 4000 - 5000 rpm for 5 - 10 min, take the supernatant, and freeze-dry to obtain the mulberry leaf extract.

8. The branched-chain fatty acid preparation for improving the growth performance of calves according to claim 1, characterized in that, The branched-chain fatty acid is any one of 12-methyltridecanoic acid, 13-methyltetradecanoic acid, and 14-methylpentadecanoic acid; the trace element compound is any one of iron glycinate, sodium selenite, and zinc glycinate.

9. The preparation method of the branched-chain fatty acid preparation for improving the growth performance of calves according to any one of claims 1 to 8, characterized in that, It includes the following steps: uniformly mixing the formula amount of mulberry leaf extract, proanthocyanidin derivative, branched-chain fatty acid, and trace element compound to obtain a branched-chain fatty acid preparation for improving the growth performance of calves.

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