A compound for improving the immunity of poultry and its application

Abstract

The invention discloses a compound for improving the immunity of poultry, comprising the following components by mass: 7-10 parts of Astragalus-Palmitoyl Glehniae compound extract and 1-3 parts of willow bark extract. The Chinese medicine component composition prepared by reasonable compatibility using the effective ingredients in Chinese medicine raw materials has the distinct characteristics of clear mechanism of action, significant effect, safety and effectiveness, and small toxic and side effects, can effectively improve the immunity of poultry, and has the effect of preventing and treating Newcastle disease infection in poultry, and has the advantages of simple formula and simple preparation process in terms of preparation method.

Description

Technical Field

[0001] This invention relates to the technical field of veterinary medicines, specifically to a compound for enhancing the immunity of poultry and its application. Background Technology

[0002] With the rapid development of intensive and large-scale animal husbandry, the rampant overuse of Western medicines—antibiotics—in the livestock industry has not only led to drug resistance in livestock and poultry but has also entered the human body through the food chain, causing drug resistance in humans as well. This has resulted in frequent outbreaks of zoonotic diseases, with no effective treatments available. In particular, intensive and large-scale animal husbandry has led to a rising incidence of infectious diseases (characterized by fever) such as swine fever, swine influenza, foot-and-mouth disease, porcine reproductive and respiratory syndrome (PRRS), avian influenza, viral enteritis, and dysentery, resulting in extremely high mortality rates in livestock and poultry and causing enormous economic losses, posing a serious threat to the development of animal husbandry. While Western medicines—antibiotics—can significantly inhibit or kill pathogenic microorganisms, their simple structure makes them easily recognized by pathogens, leading to rapid drug resistance. Furthermore, they are not easily metabolized in livestock and accumulate, posing a risk of disability and birth defects in livestock and poultry, and can enter the human body through the food chain, posing a significant potential threat to human society. Immunization vaccines can prevent the outbreak and spread of such diseases to a certain extent. However, due to the increasingly rapid mutation rate of pathogenic microorganisms and the emergence of new super pathogenic microorganisms, the vaccines that have been developed are often ineffective in prevention or cannot keep up with the speed of pathogen mutation, resulting in a disconnect between production and application.

[0003] my country is the birthplace of Traditional Chinese Medicine (TCM) and boasts abundant medicinal resources. Most TCM herbs are non-toxic, have no side effects, and leave no drug residues. They contain rich polysaccharides, alkaloids, glycosides, amino acids, volatile oils, and other active ingredients, giving them multi-target effects. They are less affected by viral mutations, can activate immune cells, and enhance animal immunity and antiviral capabilities. Astragalus is a qi-tonifying herb, the dried root of *Astragalus mongholicus* or *Astragalus membranaceus*. Astragalus has the effects of tonifying qi and raising yang, strengthening the defensive qi and consolidating the exterior, promoting diuresis and reducing swelling, generating fluids and nourishing blood, promoting blood circulation and relieving pain, promoting pus drainage and detoxification, and promoting tissue regeneration and wound healing. Astragalus polysaccharides are important components that contribute to the medicinal effects of astragalus. Recent studies on astragalus polysaccharides have shown that they enhance immune function, have anti-tumor, antioxidant, antibacterial, and hypoglycemic effects. Hand-shaped ginseng, also known as Buddha's hand ginseng, hand ginseng, or palm ginseng, is a perennial herb belonging to the genus *Hylocereus* of the Orchidaceae family. It gets its name from its underground rhizome, which resembles a hand. It mainly grows in unpolluted thickets and riverbanks at altitudes of 2700–3600 meters on the Qinghai-Tibet Plateau and is a commonly used and valuable Tibetan medicine. Modern medical research has found that the chemical components of the rhizome mainly include glycosides, sugars, dihydrostilbenes, and phenanthrene compounds, as well as sterols, phenolic acids, and aldehydes. Scholars both domestically and internationally have conducted years of research on the chemical composition of hand-shaped ginseng. It has been reported that 71 compounds have been isolated and identified from it. In addition to its early discoveries of anti-allergic, anti-silicosis fibrosis, progenitor cell proliferation-promoting, and hepatitis B virus surface antigen-inhibiting effects, recent studies have revealed other activities related to hand-shaped ginseng, such as antioxidant activity, immunomodulation, and neuroprotective effects. Willow (Salix babylonica) has a long history of medicinal use. Ancient Egyptian texts from 1550 BC record the use of white willow leaves to relieve pain. The Compendium of Materia Medica states, "Willow is a lower-grade herb in the Materia Medica, bitter and cold in nature, non-toxic, and can treat jaundice, carbuncles, and boils." According to the Dictionary of Traditional Chinese Medicine, "Tender willow leaves or branches are cold in nature, bitter in taste, and non-toxic, possessing the effects of dispelling wind, supporting dampness, clearing damp heat, and treating jaundice-type hepatitis, rheumatoid arthritis, eczema, and endemic goiter." Currently, in China, willow leaves are used as a tea to treat hypertension. Willow bark extract, whose main component is salicin, hydrolyzes or oxidizes into salicylol and salicylic acid, is clinically used to treat fever, colds, and infections, and is considered a "natural aspirin." Salicylic glycosides are used to treat mild fever, colds, infections (influenza), acute and chronic rheumatic discomfort, headaches, and pain caused by inflammation. Currently, there are no reports on methods for effectively utilizing the extracts of Astragalus membranaceus, Panax quinquefolius, and willow bark. Summary of the Invention

[0004] In view of the above-mentioned prior art, the purpose of this invention is to provide a complex for improving the immunity of poultry and its application.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The first aspect of the present invention provides a complex for enhancing the immunity of poultry, comprising the following components in parts by weight: 7-10 parts of Astragalus membranaceus-Codonopsis pilosula compound extract and 1-3 parts of willow bark extract.

[0007] The preparation method of the Astragalus-Panax palmatum compound extract includes the following steps:

[0008] (1) Mix Astragalus membranaceus slices and Codonopsis pilosula in a mass ratio of (5-7):(2-3), pulverize and sieve to obtain a mixture;

[0009] (2) Add water to the mixture and extract at 80℃-95℃, filter, repeat the operation 1 to 3 times, combine the filtrates, and concentrate to obtain concentrated solution;

[0010] (3) Add anhydrous ethanol to the concentrate until the volume fraction of ethanol is 75%-85%, let stand, concentrate and dry to obtain Astragalus-Panax palmatum compound extract.

[0011] The method for preparing the willow bark extract includes the following steps:

[0012] (1) Crush the willow bark, sieve it, and add water as a fermentation culture medium;

[0013] (2) Add 0.8%-1.2% of the fermentation composition of willow bark to the fermentation medium and ferment at a constant temperature of 30-36℃ for 60-80 hours to obtain fermentation liquid;

[0014] (3) Filter the fermentation broth until it becomes clear and collect the filtrate;

[0015] (4) The filtrate was concentrated and dried to obtain willow bark extract.

[0016] Furthermore, in step (2), the mixture is stirred for 10 minutes every 10 hours of fermentation.

[0017] Furthermore, the fermentation composition is obtained by compounding Bacillus licheniformis CICC20514, Lactobacillus plantarum CICC22698, and Rhodopseudomonas palustris CICC23812 in a mass ratio of (3-5):(6-8):(1-2).

[0018] By using Bacillus licheniformis CICC20514, Lactobacillus plantarum CICC22698, and Rhodopseudomonas palustris CICC23812 in a specific ratio to ferment and extract willow bark, the method is highly targeted and can quickly decompose the lignin and cell wall of willow bark, allowing for better release of active ingredients and resulting in better extraction effects.

[0019] A second aspect of the present invention provides the application of the above-mentioned complex in the preparation of feed additives that enhance the immunity of poultry.

[0020] A third aspect of the present invention provides the use of the above-mentioned complex in the preparation of products for preventing and treating Newcastle disease infection in poultry.

[0021] The beneficial effects of this invention are:

[0022] The pharmacology of each component in the traditional Chinese medicine composition of the present invention is as follows:

[0023] Astragalus, sweet and slightly warm, can replenish qi and raise yang, strengthen the exterior and stop sweating, promote diuresis and reduce swelling, generate fluids and nourish blood, promote circulation and relieve pain, promote the elimination of toxins and pus, and promote the healing of sores and tissues. In this formula, it can play the role of replenishing qi and strengthening the exterior, promoting qi circulation and relieving blood stasis, and thus promote the upward movement of clear qi and downward movement of turbid qi.

[0024] Palm ginseng nourishes qi and blood, promotes the production of body fluids and quenches thirst. It treats cough and asthma due to lung deficiency, emaciation due to overwork, neurasthenia, chronic diarrhea, blood loss, leukorrhea, insufficient lactation, and chronic hepatitis.

[0025] Willow bark extract, whose main component is salicin, is hydrolyzed or oxidized into salicylol and salicylic acid. It is used clinically to treat fever, colds and infections and is known as "natural aspirin". Salicin is used to treat mild fever, colds, infections (influenza), acute and chronic rheumatic discomfort, headaches and pain caused by inflammation.

[0026] This invention is a Chinese medicine composition prepared by rationally combining the effective components in Chinese medicinal raw materials. It has the distinct characteristics of clear mechanism of action, significant effect, safety and effectiveness, and low toxicity and side effects. It can effectively improve the immunity of poultry and prevent Newcastle disease infection in poultry. Moreover, it has the advantages of simple formula and simple preparation process. Detailed Implementation

[0027] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0028] As described in the background section, while Western medicines—antibiotics—can significantly inhibit or kill pathogenic microorganisms, their simple structure makes them easily recognized by pathogens, leading to rapid drug resistance. Furthermore, they are not easily metabolized in livestock and accumulate. While vaccines can prevent outbreaks and transmission of such diseases to some extent, the increasingly rapid mutation rate of pathogenic microorganisms and the emergence of new super-pathogens often render existing vaccines ineffective or unable to keep pace with pathogen mutations, resulting in a disconnect between production and application. Traditional Chinese medicine (TCM) contains abundant polysaccharides, alkaloids, glycosides, amino acids, volatile oils, and other active ingredients, giving it multi-target effects. It is less affected by viral mutations, can activate immune cells, and enhance animal immunity and antiviral capabilities.

[0029] Based on this, the inventors consulted numerous relevant documents and reports, selecting various traditional Chinese medicine components that can enhance immunity, including Astragalus membranaceus, Epimedium, Codonopsis pilosula, Angelica sinensis, Lycium barbarum, Atractylodes macrocephala, and Panax quinquefolius. Additionally, considering that willow bark extract, whose main component is salicin, is commonly used to treat mild fever, colds, infections, acute and chronic rheumatic discomfort, headaches, and pain caused by inflammation, the inventors hypothesized that combining willow bark extract with the aforementioned immune-enhancing traditional Chinese medicine components might have unexpected effects in preventing and treating Newcastle disease infection in chickens. Based on modern traditional Chinese veterinary medicine theory, various formulations were scientifically developed, and the effects of different formulations and dosages of the complex on enhancing chicken immunity and preventing Newcastle disease infection were studied. It was found that combining the Astragalus membranaceus-Panax quinquefolius compound extract with willow bark extract has a synergistic effect in enhancing chicken immunity. Finally, a compound for enhancing the immunity of poultry was obtained, the effective components of which include 7-10 parts of Astragalus membranaceus-Panax quinquefolius compound extract and 1-3 parts of willow bark extract.

[0030] Astragalus-Panax palmatum compound extract was prepared by the following method:

[0031] (1) Mix Astragalus membranaceus slices and Codonopsis pilosula in a mass ratio of (5-7):(2-3), pulverize and sieve to obtain a mixture;

[0032] (2) Add water to the mixture and extract at 80℃-95℃, filter, repeat the operation 1 to 3 times, combine the filtrates, and concentrate to obtain concentrated solution;

[0033] (3) Add anhydrous ethanol to the concentrate until the volume fraction of ethanol is 75%-85%, let stand, concentrate and dry to obtain Astragalus-Panax palmatum compound extract.

[0034] Willow bark extract was prepared by the following method:

[0035] (1) Crush the willow bark, sieve it, and add water as a fermentation culture medium;

[0036] (2) Add 0.8%-1.2% of the fermentation composition of willow bark to the fermentation medium and ferment at a constant temperature of 30-36℃ for 60-80 hours to obtain fermentation liquid;

[0037] (3) Filter the fermentation broth until it becomes clear, and collect the filtrate;

[0038] (4) The filtrate was concentrated and dried to obtain willow bark extract.

[0039] The fermentation composition is obtained by compounding Bacillus licheniformis CICC20514, Lactobacillus plantarum CICC22698, and Rhodopseudomonas palustris CICC23812 in a mass ratio of (3-5):(6-8):(1-2).

[0040] To enable those skilled in the art to better understand the technical solution of this application, the technical solution of this application will be described in detail below with reference to specific embodiments.

[0041] The test materials used in the embodiments of this invention are all conventional test materials in the art and can be purchased through commercial channels.

[0042] In this invention, both Astragalus membranaceus and Codonopsis pilosula were purchased from Beijing Tongrentang.

[0043] The willow bark is made from fresh white willow bark that is more than two years old, after being washed and dried.

[0044] The Bacillus licheniformis CICC20514, Lactobacillus plantarum CICC22698, and Rhodopseudomonas palustris CICC23812 used in this invention were purchased from the China Industrial Microbial Culture Collection Center (CICC).

[0045] The Astragalus-Panax palmatum compound extract used in this invention is prepared by the following method:

[0046] (1) Mix Astragalus membranaceus slices and Codonopsis pilosula in a mass ratio of 5:2, pulverize them and pass them through a 100-mesh sieve to obtain a mixture;

[0047] (2) Extract the mixture with 10 times the amount of water at 85°C for 3 hours. After extraction, filter and collect the filtrate. Repeat the operation twice, combine the filtrates, and obtain the concentrated solution.

[0048] (3) Add 95% ethanol to the concentrate until the volume fraction of ethanol is 80%, let stand for 12 hours, concentrate the supernatant, dry under reduced pressure at 70°C to obtain the extract, and pulverize it twice through a 150-mesh sieve to obtain the Astragalus-Panax palmatum compound extract.

[0049] The willow bark extract used in this invention is prepared by the following method:

[0050] (1) After crushing the willow bark, pass it through a 100-mesh sieve and use 7 times the weight of the willow bark in water heated to 35°C as a fermentation medium;

[0051] (2) Add 1% of the fermentation composition of willow bark to the fermentation medium and ferment at 35°C for 80 hours, stirring for 10 minutes every 10 hours to obtain the fermentation liquid.

[0052] (3) Filter the fermentation broth until it becomes clear and collect the filtrate;

[0053] (4) Heat the filtrate to concentrate it into a paste, and dry the paste into a dry powder at 120°C to obtain willow bark extract.

[0054] The fermentation composition is obtained by compounding Bacillus licheniformis CICC20514, Lactobacillus plantarum CICC22698, and Rhodopseudomonas palustris CICC23812 in a mass ratio of 3:6:1.

[0055] Example 1: Preparation of feed additives to enhance the immunity of poultry

[0056] 1. Raw material composition (parts by weight): 7 parts Astragalus-Panax palmatum compound extract, 1 part Willow bark extract.

[0057] 2. Preparation steps:

[0058] The Astragalus-Panax ginseng compound extract and willow bark extract were ultra-finely pulverized, passed through an 800-mesh sieve, mixed for 10 minutes, and dried to obtain a poultry feed additive.

[0059] Example 2: Preparation of feed additives to enhance the immunity of poultry

[0060] 1. Raw material composition (parts by weight): 8.5 parts of Astragalus membranaceus-Panax ginseng compound extract and 2 parts of willow bark extract.

[0061] 2. Preparation steps:

[0062] The Astragalus-Panax ginseng compound extract and willow bark extract were ultra-finely pulverized, passed through an 800-mesh sieve, mixed for 10 minutes, and dried to obtain a poultry feed additive.

[0063] Example 3: Preparation of feed additives to enhance the immunity of poultry

[0064] 1. Raw material composition (parts by weight): 10 parts Astragalus-Panax palmarosa compound extract, 3 parts Willow bark extract.

[0065] 2. Preparation steps:

[0066] The Astragalus-Panax ginseng compound extract and willow bark extract were ultra-finely pulverized, passed through an 800-mesh sieve, mixed for 10 minutes, and dried to obtain a poultry feed additive.

[0067] Experimental Example 1: Determination of Enhanced Immunity

[0068] 1. Test Methods

[0069] 300 one-day-old broilers were purchased from Taian Dongyue Poultry Co., Ltd. Basic feed was prepared according to the "National Standard for Chicken Feeding - Nutritional Requirements of Broiler Chickens" (ZBB43005-86) and they were fed and managed in a routine manner. At 8 days of age, 200 robust broiler chickens were selected and randomly divided into 4 groups. The control group (CK) was fed a basal diet at 16-20 days and 29-33 days of age. The T1 treatment group was fed a basal diet and the feed additive prepared in Example 1 at 16-20 days and 29-33 days of age, with the feed additive accounting for 0.5% of the basal diet weight. The T2 treatment group was fed a basal diet and Astragalus-Codonopsis pilosula compound extract at 16-20 days and 29-33 days of age, with the Astragalus-Codonopsis pilosula compound extract accounting for 0.5% of the basal diet weight. The T3 treatment group was fed a basal diet and willow bark extract at 16-20 days and 29-33 days of age, with the willow bark extract accounting for 0.5% of the basal diet weight. All four treatment groups were fed only the basal diet for the remaining time. All four treatment groups were immunized with Newcastle disease vaccine via eye drops and nasal drops at 11 and 25 days of age, 2 doses per bird. The rearing measures and feeding management of all groups were exactly the same.

[0070] At 40 days of age, 10 chickens were randomly selected from each group, and 4 mL of blood was collected from the subwing vein. The blood samples were sent to the Central Laboratory of the College of Animal Science and Technology of Shandong Agricultural University for immunoturbidimetric assay to detect the levels of immunoglobulins IgG, IgA, and IgM in the serum. The changes and average values ​​were calculated.

[0071] CD4 was analyzed by flow cytometry. + CD8 + T lymphocyte subsets, lymphocytes collected, 1000 rpm min -1 Centrifuge for 5 min, wash twice with PBS. Resuspend cells in 100 μL, add anti-CD4-FITC and anti-CD8-PE antibodies, and incubate in the dark for 30 min. Wash once with PBS, and repeat the flow cytometry experiment 4 times.

[0072] The ND-HI antibody titer was tested in accordance with the literature "Preparation of Polysaccharide from Yupingfeng and Study on its In Vivo and In Vivo Enhancement of Immunotherapy" (Master's Thesis, Shandong Agricultural University, 2015).

[0073] Method for calculating weight change: Weigh each 1-day-old broiler before the experiment and take the average weight. This average weight is the pre-experiment average weight. Weigh each surviving broiler again at 40 days of age and take the average weight. This average weight is the post-experiment average weight. The difference between the average weight before and after the experiment is the weight change. Weighing time: Half an hour before morning feeding.

[0074] 2. Test Results

[0075] Table 1. Effects of feed additives on chicken body weight and immunoprotein content.

[0076] Group Change in body weight (kg) IgG (g / L) IgM (g / L) IgA (g / L) T1 2.852±0.211 8.876±0.412 1.777±0.022 2.214±0.087 T2 2.522±0.145 5.121±0.113 1.529±0.034 1.883±0.021 T3 2.513±0.137 4.801±0.887 1.311±0.017 1.811±0.073 CK 2.476±0.154 4.211±0.223 1.223±0.079 1.259±0.066

[0077] As shown in Table 1, the combination of Astragalus membranaceus-Codonopsis pilosula compound extract and willow bark extract in this invention resulted in significant increases in IgG, IgM, and IgA levels compared to the control group (CK) in the T1 treatment group (110.78%, 45.30%, and 75.85%, respectively). In the T2 treatment group (fed only with Astragalus membranaceus-Codonopsis pilosula compound extract), IgG, IgM, and IgA levels increased by 21.61%, 25.02%, and 49.56% compared to the control group (CK). In the T3 treatment group (fed only with willow bark extract), IgG, IgM, and IgA levels increased by 14.01%, 7.20%, and 43.84% compared to the control group (CK). This invention demonstrates a synergistic effect in enhancing the levels of immune proteins in chickens by combining Astragalus membranaceus-Codonopsis pilosula compound extract with willow bark extract.

[0078] Table 2. Effects of feed additives on chicken lymphocytes and ND-HI antibody levels.

[0079] Group ND-HI antibody <![CDATA[CD4 + T / %]]> <![CDATA[CD8 + T / %]]> <![CDATA[CD4 + / CD8 + ]]> T1 8.50±0.289 32.774±0.321 18.987±0.046 1.726±0.102 T2 6.50±0.284 27.131±0.241 16.725±0.067 1.619±0.214 T3 6.30±0.225 25.145±0.113 16.632±0.011 1.511±0.092 CK 5.50±0.131 22.132±0.264 15.221±0.098 1.454±0.011

[0080] As shown in Table 2, the combination of Astragalus membranaceus-Panax ginseng compound extract and willow bark extract in this invention resulted in significantly higher antibody titers in the T1 treatment group compared to the control group (CK) for ND-HI antibody titers and CD4 antibody titers. + lymphocyte percentage, CD8 + lymphocyte percentage and CD4 + / CD8 + The ratios were all significantly higher than those of the control group (CK). This invention demonstrates that the combination of Astragalus membranaceus-Panax ginseng compound extract and willow bark extract has a synergistic effect in increasing the percentage of chicken lymphocytes and the level of ND-HI antibodies in vivo.

[0081] Experimental Example 2: Prevention and Control of Newcastle Disease Virus Infection

[0082] 1. Test Methods

[0083] Forty 24-day-old broiler chickens exhibiting lethargy and reduced appetite, purchased from Taian Dongyue Poultry Co., Ltd., were selected. They were excreting green feces, and PCR testing confirmed Newcastle disease infection. A basal feed was formulated according to the "National Standard for Chicken Feeding—Nutritional Requirements for Broiler Chickens" (ZBB43005-86), and they were raised using standard feeding methods. They were randomly divided into four groups (100 chickens / group, 10 chickens / cage, housed in 40 cages). The control group was fed the basal feed; the K1 treatment group was fed the basal feed and the feed additive prepared in Example 1, with the feed additive comprising 0.5% of the basal feed weight; the K2 treatment group was fed the basal feed and Astragalus-Codonopsis pilosula compound extract, with the Astragalus-Codonopsis pilosula compound extract comprising 0.5% of the basal feed weight; and the K3 treatment group was fed the basal feed and willow bark extract, with the willow bark extract comprising 0.5% of the basal feed weight. All groups received identical rearing and feeding management.

[0084] The entire experiment involved daily thorough cleaning and disinfection. Starting from the first day after drug administration, clinical changes in each group of broilers were observed and recorded daily, including their mental state, appetite, respiratory rales, and mortality. All dead broilers underwent necropsy to determine the cause of death. Observations were conducted continuously for fifteen days, and clinical efficacy and average weight gain were statistically analyzed.

[0085] Average weight gain calculation method: Weigh each broiler chicken before the experiment and take the average weight. This average weight is the average weight before the experiment. After the experiment, weigh each surviving broiler chicken again and take the average weight. This average weight is the average weight after the experiment. The difference between the average weight before and after the experiment is the average weight gain. Weighing time: Half an hour before morning feeding.

[0086] Clinical efficacy evaluation criteria:

[0087] Effective: After the experiment, the chickens were lively and energetic, with no adverse effects whatsoever;

[0088] Ineffective: After the experiment, the broilers showed obvious symptoms of disease (depression, ruffled feathers, drooping wings, reduced or no appetite, dark purple comb, increased nasal discharge, gurgling breathing or open-mouth breathing, diarrhea, excretion of yellow or yellow-green watery feces, death of the chickens, and necropsy showing typical septicemia lesions).

[0089] Effectiveness = Number of effective cases / 100 × 100%

[0090] 2. Test Results

[0091] Table 3. Broiler chicken conditions in each group

[0092] Group Effectiveness (%) Average weight gain (g) K1 89 1377 K2 75 1234 K3 69 1211 control group 0 97

[0093] As shown in Table 3, the feed additive prepared in this invention has an efficacy rate of 89% in preventing Newcastle disease virus infection, which is 89% higher than that of the blank control group, demonstrating excellent prevention and control effects against Newcastle disease virus in chickens.

[0094] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A compound for improving the immunity of poultry, comprising the following components in parts by weight: 7-10 parts of Astragalus membranaceus-Panthera parviflora compound extract and 1-3 parts of Willow bark extract; The Astragalus membranaceus-Panthera chinensis composite extract is prepared by the following method: (1) Mixing the Astragalus slices and the palm ginseng in a mass ratio of (5-7):(2-3), crushing and sieving to obtain a mixture; (2) adding water to the mixture and extracting at 80°C-95°C, filtering, repeating the operation 1-3 times, combining the filtrate, and concentrating to obtain a concentrate; (3) adding anhydrous ethanol to the concentrated solution until the volume fraction of ethanol is 75% to 85%, allowing to stand, concentrating, and drying to obtain an astragalus-panax ginseng composite extract; The willow bark extract is prepared by the following method: (1) Grind the willow bark, sieve it, and add water as a fermentation medium; (2) adding 0.8% to 1.2% of the willow bark mass of the fermentation composition into the fermentation medium, and fermenting at a constant temperature of 30-36° C. for 60 h to 80 h to obtain a fermentation liquid; (3) Filtering the fermentation broth until it is clear and collecting the filtrate; (4) concentrating and drying the filtrate to obtain a willow bark extract; The fermentation composition is prepared by mixing Bacillus licheniformis CICC 20514, Lactobacillus plantarum CICC 22698 and Rhodopseudomonas palustris CICC 23812 in a mass ratio of (3-5): (6-8): (1-2).

2. The composite according to claim 1, characterized in that The complex is composed of the following components in parts by weight: 8.5 parts of Astragalus membranaceus-Panthera parviflora composite extract and 2 parts of Willow bark extract.

3. Use of the complex according to claim 1 or 2 in the preparation of a feed additive for improving the immunity of poultry.

4. Use of the complex according to claim 1 or 2 in the preparation of a product for preventing and treating Newcastle disease infection in poultry.