Fermented Chinese herbal medicine feed additive for improving growth performance and immune performance of poultry and preparation method of fermented Chinese herbal medicine feed additive

Abstract

The invention discloses a fermented Chinese herbal medicine feed additive for improving the growth performance and immune performance of poultry and a preparation method thereof. The fermented Chinese herbal medicine feed additive is prepared by fermenting a fermentation substrate through a compound strain, wherein the fermentation substrate comprises compound Chinese herbal medicines, auxiliary materials and fine sand; the invention relates to the technical field of feed. According to the fermented Chinese herbal medicine feed additive for improving the growth performance and immune performance of poultry and the preparation method thereof, a Chinese herbal medicine formula is reasonably selected, a fermentation process is optimized, the dissolution rate of active substances of Chinese herbal medicines is increased, and a feed product with multiple effects of improving animal immunity, promoting growth, improving meat quality, resisting bacteria, diminishing inflammation and the like is prepared; meanwhile, the problem of low bioavailability of the traditional Chinese herbal medicine feed is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of feed, in particular to a fermented Chinese herbal medicine feed additive for improving growth performance and immune performance of poultry and a preparation method thereof. BACKGROUND

[0002] As a natural product, Chinese herbal medicine has the characteristics of antibacterial and anti-inflammatory, no drug resistance, etc., and its application in the field of feed has gradually been valued. However, directly adding Chinese herbal medicine to feed has a special taste, and it is difficult to feed animals. The existing Chinese herbal medicine additives have the problems of low extraction rate of active ingredients, poor bioavailability, poor palatability, limited animal feed intake, limited efficacy of single Chinese herbal medicine, and antagonistic effect of compound formula.

[0003] Fermentation technology can utilize the metabolic action of microorganisms to decompose macromolecular substances in Chinese herbal medicine into small molecular active ingredients, improve the dissolution rate and bioavailability of effective ingredients, and also produce new active substances to enhance the efficacy of Chinese herbal medicine. Although there are some feed and additives based on fermentation of Chinese herbal medicine on the market, most of the fermentation substrates are single in nutrition, and the functional active substances are insufficient, which cannot fully play the advantages of the combination of Chinese herbal medicine and fermentation technology, and cannot meet the demand for efficient and safe feed for modern animal healthy breeding. SUMMARY

[0004] To solve the above technical problems, the present application is implemented by the following technical scheme: a fermented Chinese herbal medicine feed additive for improving growth performance and immune performance of poultry, which is prepared by fermentation of a fermentation substrate by a compound strain;

[0005] The fermentation substrate comprises compound Chinese herbal medicine, auxiliary materials and fine sand, and the mass ratio of each component is as follows: compound Chinese herbal medicine 45%-55%, auxiliary materials 30%-40%, fine sand 0.8%-1.2%, compound bacterial liquid 3%-5%, and the balance is distilled water.

[0006] The compound Chinese herbal medicine is composed of 45-55 parts of Huangqi, 30-40 parts of Huangjing, 10-20 parts of Gancao, 5-15 parts of Baizhu and 5-15 parts of Fuling;

[0007] The auxiliary materials are composed of palm kernel meal, sprayed corn husk, soybean meal and molasses in a mass ratio of 4:3:2:1;

[0008] The feed additive contains polysaccharide with a content of ≥22%, and contains glycyrrhizic acid with a mass fraction of ≥0.3% and Huangqi Jiaosu with a content of ≥0.5%;

[0009] The compound strain is mixed by Bacillus subtilis and Lactobacillus plantarum in a volume ratio of 6-8:2-4.

[0010] The feed additive contains ≥22% polysaccharides and contains ≥0.3% glycyrrhizic acid and ≥0.5% astragaloside A by mass fraction.

[0011] Preferably, the mass fractions of each component of the compound Chinese herbal medicine are: Astragalus membranaceus 50 parts, Polygonatum sibiricum 35 parts, Glycyrrhiza uralensis 15 parts, Atractylodes macrocephala 10 parts, and Poria cocos 10 parts.

[0012] The volume ratio of Bacillus subtilis to Lactobacillus plantarum in the composite strain is 7:3.

[0013] Preferably, the fine sand is quartz sand with a particle size of 0.1-0.3 mm, which is sterilized at 121℃ for 20 minutes before use.

[0014] The crude protein content of palm kernel meal in the auxiliary materials is ≥18%, the crude fiber content of sprayed corn husk is ≤12%, and the total number of viable bacteria in the compound strain is ≥1×10 CFU / mL, of which the number of viable bacteria of Bacillus subtilis is ≥7×10 CFU / mL and the number of viable bacteria of Lactobacillus plantarum is ≥3×10 CFU / mL.

[0015] A method for preparing a fermented traditional Chinese medicine feed additive to improve the growth performance and immune function of poultry includes the following steps:

[0016] Step 1: Activation of bacterial strains: Prepare Bacillus subtilis culture medium and Lactobacillus plantarum culture medium separately, sterilize at 110-120℃ for 10-20 min, cool, and then inoculate Bacillus subtilis strain BS01 and Lactobacillus plantarum strain LB04 respectively. Incubate in shake flasks at 36-38℃ and 200-240 rpm until the OD value is 0.2-0.3 to obtain single-strain activation solution, and then mix them at a volume ratio of 6-8:2-4 to obtain compound bacterial solution;

[0017] Step 2, Pretreatment of Chinese herbal medicines: Dry each component of the compound Chinese herbal medicine in an oven at 55-65℃ until the moisture content is ≤8%, pulverize and pass through a 40-60 mesh sieve, mix evenly in proportion, and sterilize by irradiation with ultraviolet light for 20-30 minutes to obtain compound Chinese herbal medicine powder;

[0018] Step 3: Preparation of fermentation substrate: Mix the compound Chinese herbal medicine powder, excipients and fine sand according to the mass ratio, add distilled water and stir until the moisture content is 45%-55%, then inoculate with compound bacterial solution and mix evenly to obtain the fermentation substrate;

[0019] Step 4, compound fermentation: Put the fermentation substrate into the fermentation tank, distribute it into breathing bags and heat seal them. Place it in an environment of 35-37℃ for 60-84 hours. Stir once every 12 hours during the fermentation process, and stir for 5-10 minutes each time.

[0020] Step 5, Post-processing: After fermentation, the product is dried in an oven at 55-65℃ until the moisture content is ≤10%, and then pulverized through a 40-mesh sieve to obtain the fermented herbal feed additive.

[0021] Preferably, in step one, the Bacillus subtilis culture medium is LB medium, the Lactobacillus plantarum culture medium is MRS medium, and the sterilization conditions are sterilization at 115°C for 15 min.

[0022] Preferably, the relative humidity of the fermentation environment in step four is controlled at 60%-70%.

[0023] Preferably, in step four, the stirring speed is 50-80 rpm, the aeration rate of the fermentation tank is 0.5-1.0 vvm, and the aeration gas is sterile air.

[0024] Preferably, the drying in step five adopts a segmented drying method: first, dry at 55℃ for 2 hours, then raise the temperature to 65℃ and dry until the moisture content is ≤10%, and turn the material over once every 30 minutes during the drying process.

[0025] This invention provides a fermented traditional Chinese medicine feed additive for improving the growth and immune performance of poultry, and its preparation method. It has the following beneficial effects:

[0026] (I) Fermented Chinese herbal medicine feed additives for improving the growth and immune performance of poultry and their preparation methods. By rationally selecting Chinese herbal medicine formulas and optimizing fermentation processes, the dissolution rate of active substances in Chinese herbal medicines is improved, and feed products with multiple effects such as improving animal immunity, promoting growth, improving meat quality, and antibacterial and anti-inflammatory properties are prepared. At the same time, the problem of low bioavailability of traditional Chinese herbal medicine feeds is solved.

[0027] (II) Fermented Traditional Chinese Medicine Feed Additives for Improving Poultry Growth and Immune Performance and Their Preparation Method: This invention utilizes a variety of traditional Chinese medicines, including Astragalus membranaceus, Polygonatum sibiricum, and Glycyrrhiza uralensis, which, after scientific formulation and fermentation, possess multiple effects such as enhancing animal immunity, promoting growth, improving meat quality, and antibacterial and anti-inflammatory properties. Specifically, Astragalus membranaceus contains active ingredients such as Astragalus polysaccharides, which can enhance the immune function of animals; Polygonatum sibiricum polysaccharides have significant immunomodulatory effects and can improve the body's non-specific immunity; and Glycyrrhizic acid has anti-inflammatory, antiviral, and immunomodulatory effects.

[0028] (III) Fermented Traditional Chinese Medicine Feed Additives and Their Preparation Methods for Improving Poultry Growth and Immune Performance: Through microbial fermentation, the macromolecules in traditional Chinese medicine are broken down into small-molecule active ingredients, effectively improving the dissolution rate and bioavailability of the active ingredients. This allows the feed additives to be better absorbed and utilized by animals, maximizing their efficacy. Adding an appropriate amount of fine sand compensates for the lack of teeth in poultry. The contraction of the gizzard, combined with the sand, grinds the food, significantly improving feed digestibility and nutrient absorption, thus ensuring the digestive health and growth performance of poultry.

[0029] (iv) Fermented Chinese herbal medicine feed additives for improving the growth and immune performance of poultry and their preparation methods. The feed products of the present invention are made from natural Chinese herbal medicines through microbial fermentation. They do not contain chemically synthesized components, have no drug residues, are safe and harmless to animals and the environment, and meet the requirements of modern green farming.

[0030] (V) Fermented Chinese herbal medicine feed additives for improving the growth and immune performance of poultry and their preparation method. The preparation process of the present invention is simple, the fermentation conditions are mild and easy to control, and it is suitable for industrial production. It can reduce production costs and improve production efficiency. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Raw material preparation;

[0033] 1. Components and specifications of the compound traditional Chinese medicine formula;

[0034] The formula is precisely proportioned according to weight: 50 parts Astragalus membranaceus (purchased from Inner Mongolia, with Astragalus membranaceus polysaccharide content ≥8%), 35 parts Polygonatum sibiricum (purchased from Anhui, with Polygonatum sibiricum polysaccharide content ≥10%), 15 parts Glycyrrhiza uralensis (purchased from Ningxia, with glycyrrhizic acid content ≥2.5%), 10 parts Atractylodes macrocephala (purchased from Zhejiang, with Atractylodes macrocephala lactone content ≥0.3%), and 10 parts Poria cocos (purchased from Yunnan, with Poria cocos polysaccharide content ≥6%).

[0035] 2. Compound microbial strains and activation materials;

[0036] Bacterial strains: Bacillus subtilis strain BS01 (laboratory accession number: LAB-BS-202301) and Lactobacillus plantarum strain LB04 (laboratory accession number: LAB-LP-202302), with viable counts ≥5×10⁻⁶. 9 CFU / g;

[0037] Culture media: LB medium for Bacillus subtilis activation (tryptone 10 g / L, yeast extract 5 g / L, sodium chloride 10 g / L, pH 7.2); MRS medium for Lactobacillus plantarum activation (tryptone 10 g / L, beef extract 10 g / L, glucose 20 g / L, sodium acetate 5 g / L, diammonium citrate 2 g / L, Tween-80 1 mL / L, magnesium sulfate 0.58 g / L, manganese sulfate 0.25 g / L, pH 6.2).

[0038] 3. Excipients and other ingredients

[0039] Additional ingredients: palm kernel meal (crude protein content 19.2%, crude fiber content 11.5%), sprayed corn husk (crude fiber content 10.8%, crude protein content 8.5%), soybean meal (crude protein content 42.3%), molasses (total sugar content ≥45%), mixed in a mass ratio of 4:3:2:1;

[0040] Fine sand: Quartz sand with a particle size of 0.1-0.3mm, sterilized by high-pressure steam at 121℃ for 20 minutes, and then cooled for later use;

[0041] Maltodextrin: DE value 15-20, food grade;

[0042] Distilled water: Meets the Class I water standard of the "Laboratory Water Specifications" (GB / T6682-2008).

[0043] III. Preparation steps of fermented Chinese herbal medicine feed additives;

[0044] (a) Activation of microbial strains;

[0045] Culture medium preparation: Prepare 1000 mL of LB medium and 1000 mL of MRS medium, and dispense them into 250 mL Erlenmeyer flasks, 100 mL per flask;

[0046] Sterilization: Place the Erlenmeyer flask containing the culture medium in an autoclave and sterilize at 115°C for 15 minutes, then allow it to cool naturally to 37°C.

[0047] Inoculation and culture: In a sterile operating table, Bacillus subtilis strain BS01 was inoculated into LB medium and Lactobacillus plantarum strain LB04 was inoculated into MRS medium, with an inoculation amount of 1% (v / v) for both.

[0048] Shake flask culture: Place the Erlenmeyer flask in a constant temperature shaker and incubate at 37℃ and 220 rpm for 8 hours, then detect the results. A value of 0.25 (within the range of 0.2-0.3) indicates the presence of a single-strain activated solution.

[0049] Preparation of compound bacterial solution: Bacillus subtilis activation solution and Lactobacillus plantarum activation solution were mixed at a volume ratio of 7:3, and the total viable count was determined to be 1.2 × 10⁻⁶. 8 CFU / mL (of which Bacillus subtilis viable count is 8.5 × 10⁻⁶) 7 CFU / mL, viable count of Lactobacillus plantarum 3.5 × 10⁻⁶ 7 (CFU / mL), for later use.

[0050] (ii) Pretreatment of Chinese herbal medicines;

[0051] Drying: Place Astragalus membranaceus, Polygonatum sibiricum, Glycyrrhiza uralensis, Atractylodes macrocephala, and Poria cocos into an electric constant temperature oven and dry at 60℃ for 4 hours until the moisture content is 6.8% (≤8%).

[0052] Crushing and sieving: Use a high-speed universal crusher to crush the dried Chinese herbs and pass them through 40-mesh and 60-mesh standard sieves in sequence. Collect the sieve material and remove the coarse residue.

[0053] Mixing and sterilization: Mix the herbal powders evenly according to the above mass ratio, spread them evenly in a sterile petri dish (thickness ≤1cm), and place them in an ultraviolet sterilization chamber for 25 minutes to obtain compound herbal powder for later use.

[0054] (III) Preparation of fermentation substrate;

[0055] Prepare a fermentation substrate with a total mass of 1000g. The amounts of each component are as follows:

[0056] Components Amount (g) Mass proportion Compound Chinese herbal medicine powder 500 50% Auxiliary materials (palm kernel meal: sprayed corn husk: soybean meal: molasses = 4:3:2:1) 300 30% Sterilized quartz sand 10 1% Compound bacteria solution 40 4% Distilled water 150 15%

[0057] The compound Chinese herbal powder, excipients, and quartz sand are placed in a sterile mixer and stirred for 5 minutes until uniform. Distilled water is added to adjust the moisture content to 50%. Finally, the compound bacterial solution is added and stirred for another 10 minutes to ensure that the bacterial solution and the substrate are in full contact, thus obtaining the fermentation substrate.

[0058] (iv) Compound fermentation;

[0059] Fermentation equipment: Fermentation tank with sand addition components, authorized by notification number CN112971182B;

[0060] Dispensing and sealing: Dispense the fermentation substrate evenly into 10 sterile breathing bags, 100g per bag, and heat seal them at 120℃ using a heat sealer to prevent air leakage;

[0061] Fermentation conditions control: The breathing bag was placed in a constant temperature and humidity incubator, and the temperature was set to 36℃, the relative humidity to 65%, and the aeration rate to 0.8vvm. During the fermentation process, the bag was stirred at 60rpm for 8 minutes every 12 hours, and the total fermentation time was 72 hours.

[0062] (v) Post-processing;

[0063] Segmented drying: After fermentation, the product in the breathing bag is taken out and spread evenly on the drying tray (thickness ≤2cm). It is then placed in an electric constant temperature oven and dried at 55℃ for 2 hours, and then the temperature is raised to 65℃ for 3 hours. During this period, the material is turned over once every 30 minutes. Finally, it is dried to a moisture content of 8.5% (≤10%).

[0064] Crushing and sieving: Crush the dried product with a universal crusher, pass it through a 40-mesh standard sieve, and collect the sieve material;

[0065] Mixing and molding: Add 20g of maltodextrin (2% by mass) to the pulverized product, put it into a mixer and stir for 15 minutes until uniform to obtain the fermented Chinese herbal feed additive product.

[0066] IV. Finished Product Testing and Performance Verification

[0067] (a) Finished product composition testing;

[0068] Testing key components of the finished product:

[0069] Polysaccharide content: determined using the phenol-concentrated sulfuric acid method, with reference to the glucose standard curve (regression equation y=8.38x+0.034, R²=0.9993), the result was 23.15%;

[0070] Glycyrrhizic acid content: determined by high performance liquid chromatography (HPLC), the result was 0.38%;

[0071] Astragaloside A content: determined by HPLC, the result was 0.56%;

[0072] Total viable count: determined by plate count method, the result was 8.2 × 10⁻⁶. 7 CFU / g, no pathogenic bacteria (Salmonella, Escherichia coli) detected.

[0073] (ii) Performance verification test of poultry farming;

[0074] Experimental design;

[0075] Experimental Groups:

[0076] Group Addition amount Control group Basic diet Test group 1 0.5% compound Chinese herbal medicine Test group 2 1% compound Chinese herbal medicine Test group 3 1.5% compound Chinese herbal medicine Test group 4 2% compound Chinese herbal medicine Test group 5 2.5% compound Chinese herbal medicine

[0077] Design environment:

[0078] Three hundred and sixty broiler chickens were selected as the research subjects and randomly divided into six groups, with six replicates per group and ten chickens per replicate. The infected group received 1 mL of Escherichia coli K88 bacterial suspension orally, while the control group received an equal volume of physiological saline orally. The experiment lasted for four weeks.

[0079] Experimental indicators;

[0080] (1) Changes in the average daily weight gain, average daily feed intake, feed conversion ratio, and other indicators of experimental animals at different time periods;

[0081] (2) The effects of fermented Chinese herbal medicine additives on the immune function of experimental animals were investigated by using serum immune indicators.

[0082] Experimental data;

[0083] (1) Growth performance;

[0084] Initial weight Final weight Average daily weight gain Average daily feed intake Feed conversion ratio Control group 40.98±0.14a 903.90±1.11c 30.82±0.03c 40.35±0.20c 1.64±0.03a 0.5% compound Chinese herbal medicine preparation 41.02±0.07a Test group 1 Test group 2 40.86±0.06b 1.55±0.02b Test group 3 41.02±0.02a 911.90±1.56b 31.11±0.06b 41.14±0.04b 1.53±0.01b Test group 4 41.08±0.02a 920.60±1.31a 31.41±0.05a 41.59±0.17a 1.44±0.03c Test group 5 Immunoglobulin A Immunoglobulin G Control group 41.12±0.13b 0.5% compound Chinese herbal medicine preparation Test group 1 40.73±0.07b 912.42±1.77b 31.13±0.07b 41.15±0.12b 1.50±0.01b

[0085] (2) Immune serum markers;

[0086] Test group 2 Test group 3 Test group 4 2.19±0.02c 2.97±0.05d Test group 5 2.25 ± 0.01 bc 3.08±0.02c 1.48 ± 0.01 bc 2.32±0.02b 3.13±0.02c 2.5% compound Chinese herbal medicine preparation 2.58±0.02a 3.39±0.03a ​ 2.59±0.03a 3.34±0.05a ​ 2.62±0.03a 3.27±0.04b

[0087] 4. Safety testing;

[0088] During the experiment, no abnormal disease occurred in any of the broiler chickens. After the experiment, five broiler chickens from each group were randomly selected to test for drug residues (sulfonamides and antibiotics) in the muscle and liver tissues. The results showed that none of them were detected, which meets the requirements of the National Food Safety Standard Maximum Residue Limits for Veterinary Drugs in Food (GB31650-2019), proving that the feed additive of the present invention is safe and residue-free.

[0089] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0090] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fermented Chinese herbal feed additive for improving the growth performance and immune performance of poultry, characterized in that: The fermentation substrate is fermented by the complex bacteria to be prepared; ​ The fermentation substrate comprises compound Chinese herbal medicine, auxiliary material and fine sand, and the mass percentage of each component is as follows: compound Chinese herbal medicine 45-55%, auxiliary material 30-40%, fine sand 0.8-1.2%, complex bacteria liquid 3-5%, and the balance is distilled water; The compound Chinese herbal medicine is composed of 45-55 parts of Astragalus, 30-40 parts of Polygonatum, 10-20 parts of licorice, 5-15 parts of Atractylodes and 5-15 parts of Poria cocos; The auxiliary material is composed of palm kernel meal, sprayed corn husk, soybean meal and molasses at a mass ratio of 4:3:2:

1. The polysaccharide content in the feed additive is greater than or equal to 22%, and the mass fraction of glycyrrhizic acid and astragaloside A is greater than or equal to 0.3% and 0.5%, respectively. The complex bacteria is mixed by Bacillus subtilis and Lactobacillus plantarum at a volume ratio of 6-8:2-4.

2. The fermented Chinese herbal feed additive for improving growth performance and immune performance of poultry according to claim 1, characterized in that: The mass parts of each component of the compound Chinese herbal medicine are as follows: 50 parts of Astragalus, 35 parts of Polygonatum, 15 parts of licorice, 10 parts of Atractylodes and 10 parts of Poria cocos. The volume ratio of Bacillus subtilis to Lactobacillus plantarum in the complex bacteria is 7:

3.

3. The fermented Chinese herbal feed additive for improving growth performance and immune performance of poultry according to claim 1, characterized in that: The fine sand is quartz sand with a particle size of 0.1-0.3 mm, which is sterilized at 121℃ for 20 min before use.

4. A method for preparing a fermented Chinese herbal feed additive for improving the growth performance and immune performance of poultry, characterized in that: The method comprises the following steps: Step one, bacteria activation: prepare Bacillus subtilis culture medium and Lactobacillus plantarum culture medium respectively, sterilize at 110-120℃ for 10-20 min, then inoculate Bacillus subtilis strain BS01 and Lactobacillus plantarum strain LB04 after cooling, shake flask culture at 36-38℃ and 200-240 rpm until the OD value is 0.2-0.3, obtain single bacteria activation liquid, and then mix at a volume ratio of 6-8:2-4 to obtain complex bacteria liquid; Step two, Chinese herbal medicine pretreatment: dry each component of the compound Chinese herbal medicine in an oven at 55-65℃ until the water content is less than or equal to 8%, crush and pass through a 40-60 mesh sieve, mix uniformly according to the proportion, sterilize by ultraviolet lamp irradiation for 20-30 min, and obtain compound Chinese herbal medicine powder; Step three, fermentation substrate preparation: mix the compound Chinese herbal medicine powder, auxiliary material and fine sand according to the mass ratio, add distilled water and stir until the water content is 45-55%, then add the complex bacteria liquid and mix uniformly to obtain the fermentation substrate; Step four, complex fermentation: put the fermentation substrate into the fermentation tank, divide and seal in the respiratory bag, and ferment at 35-37℃ for 60-84 h, stir every 12 h during the fermentation process, and each time for 5-10 min; Step five, post-treatment: after the fermentation is completed, dry the product in an oven at 55-65℃ until the water content is less than or equal to 10%, crush and pass through a 40 mesh sieve, and obtain the fermented Chinese herbal medicine feed additive.

5. The method for preparing the fermented Chinese herbal feed additive for improving the growth performance and immune performance of poultry according to claim 4, characterized in that: In step one, the Bacillus subtilis culture medium is LB medium, the Lactobacillus plantarum culture medium is MRS medium, and the sterilization condition is 115℃ for 15 min.

6. The method for preparing the fermented Chinese herbal feed additive for improving the growth performance and immune performance of poultry according to claim 4, characterized in that: In step four, the relative humidity of the fermentation environment is controlled at 60-70%.

7. The method for preparing the fermented Chinese herbal feed additive for improving the growth performance and immune performance of poultry according to claim 6, characterized in that: In step four, the stirring speed is 50-80 rpm, the aeration amount of the fermentation tank is 0.5-1.0vvm, and the aeration gas is sterile air.

8. The method for preparing the fermented Chinese herbal feed additive for improving the growth performance and immune performance of poultry according to claim 4, characterized in that, The drying in step five is carried out in a segmented manner: first drying at 55℃ for 2h, then increasing the temperature to 65℃ until the moisture content is less than or equal to 10%, and turning the material every 30min during the drying process.