Eucommia ulmoides leaf compound feed additive capable of improving animal immunity and preparation method of eucommia ulmoides leaf compound feed additive

Abstract

The invention belongs to the technical field of feed additives, and particularly relates to a folium cortex eucommiae compound feed additive capable of improving animal immunity and a preparation method of the folium cortex eucommiae compound feed additive. The preparation method of the folium cortex eucommiae compound feed additive comprises the following steps: weighing the folium cortex eucommiae extract, the caulis clematidis armandii extract, the multivitamins, the tremella polysaccharide and the complex microbial inoculants; inoculating the folium cortex eucommiae extract and the caulis clematidis armandii extract into a fermentation culture medium for culturing to obtain fermentation liquor, and finally obtaining a fermentation product; and crushing tremella polysaccharide, and mixing the crushed tremella polysaccharide with the fermentation product, multivitamins and complex microbial inoculants to obtain the folium cortex eucommiae compound feed additive. The folium cortex eucommiae compound feed additive for improving animal immunity is added into feed, so that the growth and development capability of animals can be effectively promoted, the immunity of the animals is improved, and the folium cortex eucommiae compound feed additive has a wide application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of feed additives, and particularly relates to a eucommia leaf composite feed additive capable of improving animal immunity and a preparation method thereof. Background Art

[0002] With increasing attention to food safety and environmental protection, the use of traditional antibiotic additives is being restricted due to concerns about drug resistance. Feed additives are substances added to feed in small or trace amounts to enhance animal growth performance, improve feed utilization, boost immunity, and prevent disease. With the rapid development of the animal husbandry industry, research on feed additives is gaining increasing attention. Since feed often contains chemical drugs and antibiotics, they not only pollute the environment, but their residues are also increasingly harmful to human health through the food chain. Currently, my country urgently needs highly effective, low-toxic, and residue-free feed additives to replace traditional drugs, ensuring both animal health and food safety.

[0003] Due to their natural nutrients and special antibacterial substances, Chinese herbal feed additives offer significant advantages in promoting animal growth, enhancing immunity, and preventing and treating diseases. Eucommia leaves, a key Chinese herbal resource, contain active ingredients similar to those found in Eucommia bark. Over 70 organic compounds and at least 15 inorganic mineral elements have been isolated and identified, broadly categorized as iridoids, lignans, flavonoids, eucommia gum, phenylpropanoids, phenols, amino acids, polysaccharides, fatty acids, and vitamins. These ingredients can scavenge free radicals in animals, reduce oxidative stress-induced cell damage, maintain normal physiological functions, and thus enhance animal immunity. Furthermore, a study published by the Economic Forestry Research and Development Center of the Chinese Academy of Forestry, titled "Research Progress in Eucommia Feed Additives," demonstrates that Eucommia leaves, like Eucommia bark, enhance the growth performance and immunity of poultry and livestock. The abundance of Eucommia leaves provides a promising foundation for the development of functional Eucommia feed.

[0004] Based on the above background, the present invention provides a Eucommia leaf compound feed additive for improving animal immunity, aiming to solve the safety problems of traditional additives while significantly improving animal immunity and growth performance. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the first object of the present invention is to provide a method for preparing a composite feed additive of Eucommia ulmoides leaves for improving animal immunity.

[0006] The technical solution adopted in the first object of the present invention is:

[0007] A method for preparing a composite feed additive containing eucommia leaves for improving animal immunity comprises the following steps:

[0008] (1) Weigh the raw materials according to the weight ratio: Eucommia ulmoides leaf extract, Tibetan Atractylodes lancea extract, multivitamins, Tremella fuciformis polysaccharide, and composite bacterial agent;

[0009] (2) inoculating the Eucommia ulmoides leaf extract and the Tibetan Atractylodes lancea extract into a fermentation medium to obtain a fermentation broth, filtering, and drying to obtain a fermentation product; the fermentation medium comprises: glucose, butyl-D-ribuloside, yeast extract, peptone, potassium dihydrogen phosphate, and water;

[0010] (3) The Tremella fuciformis polysaccharide is crushed and then mixed with fermentation products, compound vitamins, and compound bacterial agents to obtain a Eucommia ulmoides leaf compound feed additive.

[0011] Preferably, the weight proportions of the raw materials in step (1) are: 15-30 parts of Eucommia leaf extract, 3-12 parts of Tibetan Atractylodes extract, 3-8 parts of complex vitamins, 2-5 parts of Tremella polysaccharide, and 2-7 parts of composite bacterial agent.

[0012] Preferably, the composite bacterial agent in step (1) is composed of Bacillus subtilis powder, yeast powder, and lactic acid bacteria powder in a mass ratio of (6-8): (4-9): (3-5).

[0013] Preferably, the vitamin complex in step (1) consists of vitamin A, vitamin D3, vitamin E, and vitamin K in a mass ratio of (13-16):(2-6):(60-80):(6-8).

[0014] Preferably, the components in the fermentation medium in step (2) are calculated by weight as follows: 15-30% glucose, 1.0-2.5% butyl-D-ribuloside, 0.5-1% yeast extract, 1.0-3.2% peptone, 0.5-2.5% potassium dihydrogen phosphate and the balance water.

[0015] Preferably, the culture temperature in step (2) is 30-37° C. and the culture time is 4-8 h.

[0016] Preferably, the preparation method of the Eucommia ulmoides leaf extract is as follows:

[0017] (1) Washing, drying, and crushing the Eucommia ulmoides leaves to obtain Eucommia ulmoides leaf powder;

[0018] (2) adding 10-12 times the weight of Eucommia leaf powder to water and soaking for 2-3 hours, followed by decocting for 4-6 hours; filtering and centrifuging to collect the first filtrate and the first filtrate residue;

[0019] (3) Then, 10-12 times the weight of water is added to the first filter residue and soaked for 2-3 hours, followed by decoction for 3-4 hours; the second filtrate is collected after filtration and centrifugation, and the first filtrate and the second filtrate are combined, concentrated, and freeze-dried to obtain the Eucommia ulmoides extract.

[0020] Preferably, the preparation method of the Caulis Tibetanae extract is as follows:

[0021] (1) Wash, dry, and crush the Tibetan Atractylodes lancea to obtain Tibetan Atractylodes lancea powder;

[0022] (2) adding 10-15 times the weight of the Tibetan wood powder to water and soaking it for 2-3 hours, and then boiling it for 3-4 hours; filtering and centrifuging to collect the first filtrate and the first filter residue;

[0023] (3) Then, 10-15 times the weight of water is added to the first filter residue and soaked for 2-3 hours, followed by decoction for 2-3 hours; after filtering and centrifugation, the second filtrate is collected, the first filtrate and the second filtrate are combined, concentrated, and freeze-dried to obtain a Tibetan Akebia extract.

[0024] The second object of the present invention is to provide a eucommia leaf compound feed additive for improving animal immunity.

[0025] The technical solution adopted for the second purpose of the present invention is:

[0026] A eucommia leaf compound feed additive for improving animal immunity is prepared according to the above-mentioned preparation method of the eucommia leaf compound feed additive for improving animal immunity.

[0027] Compared with the prior art, the beneficial effects of the present invention are mainly:

[0028] The present invention prepares a Eucommia leaf compound feed additive for improving animal immunity, comprising Eucommia leaf extract, Tibetan Caulis Atractylodes extract, complex vitamins, Tremella polysaccharide, and a composite bacterial agent. The Tibetan Caulis Atractylodes extract and the Eucommia leaf extract have a synergistic effect, effectively promoting the growth and development of animals and enhancing their immunity. Furthermore, the addition of butyl-D-ribuloside to the fermentation medium enhances the efficacy of the Tibetan Caulis Atractylodes extract and the Eucommia leaf extract. Experimental results show that the Eucommia leaf compound feed additive can be added to feed to effectively promote the growth and development of animals, reduce feed-to-meat ratios, enhance animal immunity, improve feed utilization, and thereby increase the economic benefits of the aquaculture industry. The additive has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is the IgG (immunoglobulin G) content in piglet serum;

[0030] Figure 2 It is the content of IgM (immunoglobulin M) in piglet serum. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be further described below in conjunction with specific embodiments. However, it should be understood by those skilled in the art that the following examples are only intended to illustrate the present invention and should not be construed as limiting the present invention. Specific conditions not specified in the examples are to be followed according to conventional conditions or the conditions recommended by the manufacturer. All reagents or instruments used, unless otherwise specified, are conventional products obtained from commercial channels.

[0032] The Bacillus subtilis powder, yeast powder, and lactic acid bacteria powder used in the examples of the present invention were from Henan Guoxin Biotechnology Co., Ltd.

[0033] The preparation method of the Eucommia ulmoides leaf extract used in the embodiment of the present invention is as follows:

[0034] (1) Washing, drying, and crushing the Eucommia ulmoides leaves to obtain Eucommia ulmoides leaf powder;

[0035] (2) adding 12 times the weight of Eucommia leaf powder to water and soaking for 3 hours, followed by decocting for 6 hours; filtering and centrifuging to collect the first filtrate and the first filtrate residue;

[0036] (3) Then, 12 times the weight of water was added to the first filter residue and soaked for 3 hours, followed by decocting for 4 hours; the second filtrate was collected after filtration and centrifugation, and the first filtrate and the second filtrate were combined, concentrated, and freeze-dried to obtain the Eucommia ulmoides extract.

[0037] The preparation method of the Caulis Tibetanae extract used in the embodiments of the present invention is as follows:

[0038] (1) Wash, dry, and crush the Tibetan Atractylodes lancea to obtain Tibetan Atractylodes lancea powder;

[0039] (2) adding 15 times the weight of the Tibetan wood powder to water and soaking for 3 hours, followed by decocting for 4 hours; filtering and centrifuging to collect the first filtrate and the first filter residue;

[0040] (3) Then, 15 times the weight of water was added to the first filter residue and soaked for 3 hours, followed by decocting for 3 hours; the second filtrate was collected after filtration and centrifugation, and the first filtrate and the second filtrate were combined, concentrated, and freeze-dried to obtain a Tibetan Akebia extract.

[0041] Example 1

[0042] A method for preparing a composite feed additive containing eucommia leaves for improving animal immunity comprises the following steps:

[0043] (1) According to the weight ratio, 22 parts of Eucommia ulmoides leaf extract, 7 parts of Tibetan Atractylodes lancea extract, 5 parts of complex vitamins, 4 parts of Tremella fuciformis polysaccharide, and 4 parts of composite bacterial agent were weighed; the composite bacterial agent was composed of Bacillus subtilis powder, yeast powder, and lactic acid bacteria powder in a mass ratio of 7:6:4; the complex vitamins were composed of vitamin A, vitamin D3, vitamin E, and vitamin K in a mass ratio of 15:4:70:7.

[0044] (2) The extract of Eucommia ulmoides leaves and the extract of Tibetan Atractylodes lancea were added to a fermentation medium at 33° C. and cultured for 6 hours to obtain a fermentation broth, which was filtered and dried to obtain a fermentation product; the components in the fermentation medium were calculated by weight as follows: 22% glucose, 1.7% butyl-D-ribuloside, 0.7% yeast extract, 2.1% peptone, 1.5% potassium dihydrogen phosphate, and the balance water.

[0045] (3) The Tremella fuciformis polysaccharide is crushed and then mixed with fermentation products, compound vitamins, and compound bacterial agents to obtain a Eucommia ulmoides leaf compound feed additive.

[0046] The present invention also provides a eucommia leaf composite feed additive prepared by the above preparation method and capable of improving animal immunity.

[0047] Example 2

[0048] A method for preparing a composite feed additive containing eucommia leaves for improving animal immunity comprises the following steps:

[0049] (1) According to the weight ratio, 15 parts of Eucommia ulmoides leaf extract, 3 parts of Tibetan Atractylodes lancea extract, 3 parts of complex vitamins, 2 parts of Tremella fuciformis polysaccharide, and 2 parts of composite bacterial agent were weighed; the composite bacterial agent was composed of Bacillus subtilis powder, yeast powder, and lactic acid bacteria powder in a mass ratio of 6:4:3; the complex vitamins were composed of vitamin A, vitamin D3, vitamin E, and vitamin K in a mass ratio of 13:2:60:8.

[0050] (2) The extract of Eucommia ulmoides leaves and the extract of Tibetan Atractylodes lancea are added to a fermentation medium and cultured at 30°C for 4 hours to obtain a fermentation broth, which is filtered and dried to obtain a fermentation product; the components in the fermentation medium are calculated by weight as follows: 15% glucose, 1% butyl-D-ribuloside, 0.5% yeast extract, 1.0% peptone, 0.5% potassium dihydrogen phosphate and the balance water.

[0051] (3) The Tremella fuciformis polysaccharide is crushed and then mixed with fermentation products, compound vitamins, and compound bacterial agents to obtain a Eucommia ulmoides leaf compound feed additive.

[0052] The present invention also provides a eucommia leaf composite feed additive prepared by the above preparation method and capable of improving animal immunity.

[0053] Example 3

[0054] A method for preparing a composite feed additive containing eucommia leaves for improving animal immunity comprises the following steps:

[0055] (1) According to the weight ratio, 30 parts of Eucommia leaf extract, 12 parts of Tibetan Atractylodes extract, 8 parts of complex vitamins, 5 parts of Tremella polysaccharide, and 7 parts of composite bacterial agent were weighed; the composite bacterial agent was composed of Bacillus subtilis powder, yeast powder, and lactic acid bacteria powder in a mass ratio of 8:9:5; the complex vitamins were composed of vitamin A, vitamin D3, vitamin E, and vitamin K in a mass ratio of 16:6:80:8.

[0056] (2) The extract of Eucommia ulmoides leaves and the extract of Tibetan Atractylodes lancea were added to a fermentation medium and cultured at 37°C for 8 hours to obtain a fermentation broth, which was filtered and dried to obtain a fermentation product; the components in the fermentation medium were calculated by weight as follows: 30% glucose, 2.5% butyl-D-ribuloside, 1% yeast extract, 3.2% peptone, 2.5% potassium dihydrogen phosphate, and the balance water.

[0057] (3) The Tremella fuciformis polysaccharide is crushed and then mixed with fermentation products, compound vitamins, and compound bacterial agents to obtain a Eucommia ulmoides leaf compound feed additive.

[0058] The present invention also provides a eucommia leaf composite feed additive prepared by the above preparation method and capable of improving animal immunity.

[0059] Comparative Example 1

[0060] The difference between Comparative Example 1 and Example 1 is that the extract of Caulis Tiliopteris is omitted from the ingredients of the Eucommia ulmoides leaf compound feed additive for improving animal immunity, and the rest are the same as in Example 1.

[0061] Comparative Example 2

[0062] The difference between Comparative Example 2 and Example 1 is that the Tibetan Atractylodes Caulis extract in the ingredients of the Eucommia leaf compound feed additive for improving animal immunity is replaced with Eucommia leaf extract, and the rest are the same as Example 1.

[0063] Comparative Example 3

[0064] The difference between Comparative Example 3 and Example 1 is that butyl-D-ribuloside is omitted from the fermentation medium components in step (2), and the rest are the same as in Example 1.

[0065] Test Example 1

[0066] Lymphocyte proliferation test:

[0067] 70 healthy SPS-grade mice were selected and randomly divided into a control group, Example 1 group, Example 2 group, Example 3 group, Comparative Example 1 group, Comparative Example 2 group, and Comparative Example 3 group, with 10 mice in each group. Before the start of the experiment, all mice were subjected to hematological examinations and pathogen detection to ensure that their health status was consistent. Preparation of Eucommia leaf compound feed additive solution: The Eucommia leaf compound feed additive prepared by the above-mentioned groups was weighed, and distilled water was used to prepare an Eucommia leaf compound feed additive solution containing a sample concentration of 500 mg / mL. After one week of adaptive feeding, each group of mice was gavaged with the Eucommia leaf compound feed additive solution of the corresponding group at a dose of 2 mL / kg; the control group was gavaged with distilled water at a dose of 2 mL / kg. Each group was gavaged three times a day for 30 consecutive days. Twelve hours after the last oral gavage, the spleens of the mice were removed, ground into single-cell suspensions, and aliquoted into 24-well plates (1 mL / well). ConA (75 μL / well) or no ConA (control) was added, and the cells were incubated at 37°C, 5% CO₂ for 72 hours. Four hours before the end of the culture period, the medium was replaced with serum-free RPMI1640 and MTT (50 μL / well) was added, and the cells were incubated for another 4 hours. Following the incubation period, formazan was dissolved in acidic isopropanol and the cells were transferred to 96-well plates. Three replicates were prepared for each well, and the optical density (OD) was measured at 570 nm using a microplate reader. The results are shown in Table 1.

[0068] Table 1 Lymphocyte proliferation ability

[0069]

[0070]

[0071] The results are shown in Table 1, which shows the effect of the Eucommia leaf compound feed additive for improving animal immunity prepared by the present invention on the proliferation capacity of lymphocytes. As can be seen from the table, compared with the comparative example 1-3 group, the compound feed additive prepared by the Example 1-3 group of the present invention can significantly improve the OD value and promote the proliferation capacity of lymphocytes. This shows that the Eucommia leaf compound feed additive can effectively stimulate the proliferation of lymphocytes and enhance cellular immune function. This enhanced immune response can not only more effectively eliminate pathogens, but also provide long-term protection by forming immune memory. The specific mechanism may include activating specific signaling pathways or regulating the secretion of cytokines, thereby promoting the proliferation and activation of lymphocytes.

[0072] Test Example 2

[0073] The following is an effect test of the Eucommia leaf composite feed additive for improving animal immunity prepared in Examples 1-3 and Comparative Examples 1-3:

[0074] (1) Seventy piglets weighing approximately 8 kg were randomly divided into a control group, Example 1 group, Example 2 group, Example 3 group, Comparative Example 1 group, Comparative Example 2 group, and Comparative Example 3 group, with 10 piglets in each group. The piglets were in good health. Example 1 group: 2% of the weight of the basic feed was added to the basal feed of the Eucommia leaf compound feed additive for improving animal immunity prepared in Example 1; Control group: No Eucommia leaf compound feed additive for improving animal immunity was added to the basal feed during the feeding process, and the other contents of the feeding feed were the same as those of Example 1 group; The remaining groups added 2% of the weight of the basic feed of the Eucommia leaf compound feed additive for improving animal immunity of the corresponding group to the basal feed. The piglets in each group had free access to food and water for 30 consecutive days; the piglet basal feed formula, in terms of mass percentage, included the following raw materials: 55% corn, 25% soybean meal, 5% fish meal, 5% soybean protein powder, 7% fish oil, 1% calcium bicarbonate, 1% salt, and 1% premix. Weigh the animals, record the average starting weight (kg / head) and the average final weight (kg / head), calculate the daily weight gain, daily feed intake, and feed-to-meat ratio, and the results are shown in Table 2.

[0075] Table 2 Effects of different feed additives on piglet growth performance

[0076]

[0077]

[0078] The results are shown in Table 2, which shows the effect of the Eucommia leaf compound feed additive prepared by the present invention for improving animal immunity on the growth performance of piglets. As can be seen from the table, compared with the comparative example 1-3 groups, the compound feed additive prepared by the examples 1-3 groups of the present invention can significantly increase the daily feed intake and daily weight gain of piglets and reduce the feed-to-meat ratio of piglets. This shows that the Eucommia leaf compound feed additive prepared by the examples 1-3 groups can effectively promote the growth and development ability of piglets, improve the utilization rate of feed, and thus promote the economic benefits of the farm.

[0079] (2) After 30 days of continuous feeding, 3 piglets in each group were selected for fasting anterior vena cava blood collection (5 mL). The blood was centrifuged at 4000 rpm for 10 min at 4°C. The upper serum was collected and the ELISA kit was used to detect the levels of immunoglobulin IgG (immunoglobulin G) and IgM (immunoglobulin M) in the serum of piglets in different groups. The test results are shown in Figure 2. Figure 1 、 Figure 2 shown.

[0080] The results are as follows Figure 1 、 Figure 2The following table shows the levels of serum immunoglobulins IgG (immunoglobulin G) and IgM (immunoglobulin M) in piglets of different groups. IgG is the most abundant immunoglobulin in the blood and can neutralize viruses, bacteria and toxins, preventing them from entering cells. IgM is the earliest antibody produced in the primary immune response and can quickly recognize and bind to pathogens. Figure 1 、 Figure 2 It can be seen that compared with the comparative examples 1-3, the feed additives for aquaculture prepared in the examples 1-3 of the present invention can significantly increase the levels of immunoglobulins IgG and IgM in the serum of piglets, thereby improving the body's immune capacity. This shows that the piglets in the examples 1-3 groups can maintain growth and development while also having high immune performance, and have broad application prospects.

[0081] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the same. The basic principles and main features of the present invention have been described above using specific implementation schemes. Modifications or substitutions may be made based on the present invention, but such modifications or substitutions do not detract from the essence of the corresponding technical solutions from the scope of protection claimed by the present invention.

Claims

1. A method for preparing a composite feed additive of Eucommia ulmoides leaves for improving animal immunity, characterized in that: The specific steps include: (1) Weigh the raw materials according to the weight ratio: Eucommia ulmoides leaf extract, Tibetan Atractylodes lancea extract, multivitamins, Tremella fuciformis polysaccharide, and composite bacterial agent; (2) inoculating the Eucommia ulmoides leaf extract and the Tibetan Atractylodes lancea extract into a fermentation medium to obtain a fermentation broth, filtering, and drying to obtain a fermentation product; the fermentation medium comprises: glucose, butyl-D-ribuloside, yeast extract, peptone, potassium dihydrogen phosphate, and water; (3) The Tremella fuciformis polysaccharide is crushed and then mixed with fermentation products, compound vitamins, and compound bacterial agents to obtain a Eucommia ulmoides leaf compound feed additive.

2. The method for preparing a compound feed additive of Eucommia ulmoides leaves for improving animal immunity according to claim 1, wherein: The weight proportions of the raw materials in step (1) are: 15-30 parts of Eucommia leaf extract, 3-12 parts of Tibetan Atractylodes extract, 3-8 parts of complex vitamins, 2-5 parts of Tremella polysaccharide, and 2-7 parts of composite bacterial agent.

3. The method for preparing a compound feed additive of Eucommia ulmoides leaves for improving animal immunity according to claim 1, characterized in that: In the step (1), the composite bacterial agent is composed of Bacillus subtilis powder, yeast powder, and lactic acid bacteria powder in a mass ratio of (6-8): (4-9): (3-5).

4. The method for preparing a compound feed additive of Eucommia ulmoides leaves for improving animal immunity according to claim 1, wherein: The vitamin complex in step (1) is composed of vitamin A, vitamin D3, vitamin E, and vitamin K in a mass ratio of (13-16):(2-6):(60-80):(6-8).

5. The method for preparing a compound feed additive of Eucommia ulmoides leaves for improving animal immunity according to claim 1, characterized in that: The components in the fermentation medium in step (2) are calculated by weight as follows: 15-30% glucose, 1.0-2.5% butyl-D-ribuloside, 0.5-1% yeast extract, 1.0-3.2% peptone, 0.5-2.5% potassium dihydrogen phosphate and the balance water.

6. The method for preparing a compound feed additive of Eucommia ulmoides leaves for improving animal immunity according to claim 1, characterized in that: The culture temperature in step (2) is 30-37° C. and the culture time is 4-8 h.

7. The method for preparing a compound feed additive of Eucommia ulmoides leaves for improving animal immunity according to claim 1, characterized in that: The preparation method of the Eucommia ulmoides leaf extract is as follows: (1) Washing, drying, and crushing the Eucommia ulmoides leaves to obtain Eucommia ulmoides leaf powder; (2) adding 10-12 times the weight of Eucommia leaf powder to water and soaking for 2-3 hours, followed by decocting for 4-6 hours; filtering and centrifuging to collect the first filtrate and the first filtrate residue; (3) Then, 10-12 times the weight of water is added to the first filter residue and soaked for 2-3 hours, followed by decoction for 3-4 hours; the second filtrate is collected after filtration and centrifugation, and the first filtrate and the second filtrate are combined, concentrated, and freeze-dried to obtain the Eucommia ulmoides extract.

8. The method for preparing a compound feed additive of Eucommia ulmoides leaves for improving animal immunity according to claim 1, characterized in that: The preparation method of the Caulis Tibetanae extract is as follows: (1) Wash, dry, and crush the Tibetan Atractylodes lancea to obtain Tibetan Atractylodes lancea powder; (2) adding 10-15 times the weight of the Tibetan wood powder to water and soaking it for 2-3 hours, and then boiling it for 3-4 hours; filtering and centrifuging to collect the first filtrate and the first filter residue; (3) Then, 10-15 times the weight of water is added to the first filter residue and soaked for 2-3 hours, followed by decoction for 2-3 hours; after filtering and centrifugation, the second filtrate is collected, the first filtrate and the second filtrate are combined, concentrated, and freeze-dried to obtain a Tibetan Akebia extract.

9. A eucommia leaf compound feed additive for improving animal immunity, prepared according to the preparation method of the eucommia leaf compound feed additive for improving animal immunity according to any one of claims 1 to 8.

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