Feed additive for improving production performance of laying hens and application thereof

Abstract

The application discloses a feed additive for improving production performance of laying hens and application thereof, and belongs to the technical field of livestock feed. Raw materials of the feed additive include proto-catechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and rey's lactobacillus postbiotic, and the feed additive is prepared by uniformly mixing the above substances in a mass ratio of 10-20:10-20:5-10:50-75. A use method of the feed additive comprises the following steps: adding 0.01%-0.05% of the feed additive to laying hen feed directly according to the total weight of the feed; or mixing the feed additive with a carrier to prepare a premix; or mixing the feed additive with other feed additives or feed raw materials to prepare a premix or concentrated feed for feeding laying hens. The use of the feed additive can reduce the incidence of fatty liver, intestinal and oviduct inflammatory reactions of laying hens, promote the reproductive health of laying hens and improve the egg production performance; compared with a feed antibiotic additive, the feed additive has the advantages of no toxic side effects, no drug residues, no pollution and high efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of livestock feed, in particular to a feed additive for improving the production performance of laying hens and laying ducks and application thereof. BACKGROUND

[0002] Diseases such as fatty liver syndrome, intestinal toxicity syndrome and inflammation of the fallopian tube are bottleneck problems affecting the production efficiency of laying hens and laying ducks, and people usually hope to use high-quality feed additives, especially those containing antibiotics. However, there is still a lack of high-quality feed additive products with stable effects on the market, and this problem is particularly prominent with the implementation of the overall "antibiotic restriction and prohibition" in China. Therefore, effective measures need to be taken to improve the production performance of laying hens and laying ducks in the production of poultry breeding, and the current additives that can replace antibiotics in feed include Chinese herbal medicines and their extracts, acid preparations, enzyme preparations, microecological preparations, etc.

[0003] Protocatechuic aldehyde is a natural phenolic acid compound derived from Danshen or Cinnamon, and medical research reports show that it has the functions of antibacterial, anti-inflammatory, antioxidant, anti-ulcer, anti-diabetic, anti-fibrosis, anti-aging, anti-virus, anti-atherosclerosis, and protection of the heart, liver and kidney.

[0004] Benzoyl paeoniflorin is the main monoterpene glycoside component in red peony root, and has the functions of antibacterial, anti-diabetic, anti-tumor, anti-inflammatory and liver protection.

[0005] Ergosterol in sterol yeast culture can enhance the body's resistance to disease, is an important fat-soluble vitamin D2 source, and has obvious bacteriostatic and anti-tumor effects.

[0006] Lactobacillus reuteri in the probiotic of Lactobacillus reuteri has strong adhesion to intestinal mucosa, can improve the distribution of intestinal flora, antagonize harmful bacteria colonization, and avoid intestinal diseases; the probiotic of Lactobacillus reuteri contains a large amount of reuterin and mussel mucin, which can widely inhibit the growth of gram-positive bacteria, gram-negative bacteria, yeast, fungi and pathogenic fungi. SUMMARY

[0007] The present application aims to provide a feed additive, which can effectively prevent and treat fatty liver syndrome, intestinal toxicity syndrome and inflammation of the fallopian tube in laying hens and laying ducks, enhance the immune function of the intestinal tract and the fallopian tube, and improve the fat metabolism capacity of laying hens and laying ducks, thereby improving the production performance of laying hens and laying ducks. The use of the feed additive can reduce the incidence of fatty liver, inflammatory reactions in the intestinal tract and the fallopian tube, promote the reproductive health of laying hens and laying ducks, and improve the egg-laying performance; compared with feed antibiotic additives, the feed additive has the advantages of no toxic side effects, no drug residues, no pollution and high efficiency.

[0008] The present application also aims to provide the application of the feed additive and the use method of the feed additive.

[0009] The object of the present application is achieved by adopting the technical scheme as follows:

[0010] A feed additive, raw materials of which include protocatechuic aldehyde, benzoylpaeoniflorin, sterol yeast culture and lactobacillus reuteri postbiotic, and the mass ratio of the raw materials is 10-20:10-20:5-10:50-75. The sterol yeast refers to yeast capable of producing ergosterol.

[0011] As a preferred scheme of the present application, the sterol yeast is Kluyveromyces marxianus. The sterol yeast culture contains more than 1% of ergosterol.

[0012] As a preferred scheme of the present application, the lactobacillus reuteri postbiotic is obtained by a method comprising the following steps: inoculating lactobacillus reuteri into a culture medium containing poultry intestinal mucosa powder, culturing under anaerobic conditions, adding malt dextrin into the culture solution for adsorption after the end of culturing, and spray drying to obtain the lactobacillus reuteri postbiotic. Preferably, the lactobacillus reuteri is NCIMB 30242; the culture medium is MRS liquid medium; and the poultry intestinal mucosa powder is prepared as follows: after poultry is slaughtered, the intestinal tract is washed and the intestinal mucosa is scraped, and then the intestinal mucosa is sterilized, frozen with liquid nitrogen and ground to obtain the poultry intestinal mucosa powder; the content of the poultry intestinal mucosa powder in the culture medium containing the poultry intestinal mucosa powder is 30-40 g / L. The lactobacillus reuteri postbiotic contains ≥27% of bacterial protein, ≥10 10 cfu / g of lactobacillus reuteri, ≥224 mg / g of reuterin and ≥5 mg / g of mussel mucin.

[0013] The preparation method of the feed additive comprises the following steps: uniformly mixing protocatechuic aldehyde, benzoylpaeoniflorin, sterol yeast culture and lactobacillus reuteri postbiotic to obtain the feed additive.

[0014] The application of the feed additive in reducing the incidence of fatty liver in laying hens, intestinal and oviduct inflammatory reactions, promoting the reproductive health of laying hens and / or improving the egg-laying performance of laying hens.

[0015] The application of the feed additive in preparing products, wherein the products are at least one of the following products: products for preventing and treating fatty liver syndrome in laying hens, products for preventing and treating enterotoxemia syndrome in laying hens, products for preventing and treating oviduct inflammation in laying hens, products for promoting the reproductive health of laying hens, products for improving the egg-laying performance of laying hens; and the products include feed and medicine.

[0016] A product comprising the feed additive. The product is at least one of the following: a product for preventing fatty liver syndrome of laying hens, a product for preventing enterotoxism syndrome of laying hens, a product for preventing inflammation of oviduct of laying hens, a product for promoting reproductive health of laying hens, a product for improving egg production performance of laying hens; the product comprises feed and medicine.

[0017] The feed additive can be used to replace antibiotic additives in feed, and the method for using the feed additive comprises: directly adding the feed additive into feed for laying hens and laying ducks; or mixing the feed additive with a carrier to prepare a premix; or mixing the feed additive with other feed additives or feed raw materials to prepare a premix or a concentrated feed for feeding laying hens.

[0018] The feed additive for improving egg production performance of laying hens is added in an amount of 0.01% to 0.05% based on the total weight of the feed.

[0019] Compared with the prior art, the present application has the following advantages and beneficial effects: the present application solves the problems of prominent intestinal health of poultry in the post-antibiotic era, poor effect of effective feed additives, unstable efficacy and the like; and can effectively inhibit bacteria and viruses in the intestinal tract and oviduct, reduce inflammatory reactions, enhance the immune function of the intestinal tract and oviduct, and improve the fat metabolism capacity of laying hens, so as to improve the production performance of laying hens; the use of the feed additive can reduce the incidence of fatty liver of laying hens, inflammatory reactions in the intestinal tract and oviduct, promote the reproductive health of laying hens and improve the egg production performance; compared with feed antibiotic additives, the feed additive has the advantages of no toxic side effects, no drug residues, no pollution and high efficiency. DETAILED DESCRIPTION

[0020] The technical solutions of the present application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0021] The feed additive provided by the present application comprises raw materials including protocatechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and Lactobacillus reuteri postbiotic, and the mass ratio of the raw materials is 10-20:10-20:5-10:50-75. The feed additive can be obtained by uniformly mixing the raw materials with the above mass ratio.

[0022] The sterol yeast culture is prepared by culturing Kluyveromyces marxianus, and the sterol yeast culture contains more than 1% ergosterol.

[0023] The Lactobacillus reuteri postbiotic is prepared by a method comprising the following steps:

[0024] 1) Lactobacillus reuteri NCIMB 30242 single colony was inoculated into 10 mL of MRS liquid medium and cultured anaerobically at 37°C for 24 hours, at which time the number of bacteria was about 1 x 10 9 cfu / mL. Then 1 mL of the bacterial solution was inoculated into 100 mL of MRS liquid medium containing 3-4 g of AA broiler jejunum and ileum mucosa powder (which was prepared by washing the food chyme on the intestinal tissue of 35-day-old AA broiler chickens with normal saline after slaughter, scraping the intestinal mucosa, high-pressure sterilization, and then grinding to obtain the intestinal mucosa powder), and cultured anaerobically at 37°C for 24 hours, at which time the number of bacteria was about 1 x 10 10 cfu / mL. Then 100 mL of the bacterial solution was placed in a 500 L fermenter and expanded in MRS liquid medium containing 30-40 g / L of AA broiler jejunum and ileum mucosa powder for 24 hours, maintaining the temperature of the fermenter at 37°C and filling N2 to establish anaerobic fermentation conditions. After the culture was completed, 10% malt dextrin was added to the fermentation broth for adsorption, and spray drying was performed to prepare Lactobacillus reuteri postbiotic. The addition of broiler jejunum and ileum mucosa powder in the culture medium can induce Lactobacillus reuteri to produce high levels of mussel mucin.

[0025] 2) Non-targeted metabolomics and proteomics sequencing technology was used to detect and analyze the above-mentioned Lactobacillus reuteri postbiotic, and it was identified that its metabolic products included 3-hydroxypropanal, lactic acid, acetic acid, butyric acid, vitamin B2, vitamin B3, vitamin B6, vitamin B9, selenium, and mussel mucin. The Lactobacillus reuteri postbiotic functional substance prepared by the above method is rich in content, with ≥27% of bacterial protein, ≥10 10 cfu / g of Lactobacillus reuteri, ≥224 mg / g of reuterin, and ≥5 mg / g of mussel mucin.

[0026] Example 1:

[0027] The feed additive used in this example was prepared by mixing protocatechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture, and Lactobacillus reuteri postbiotic at a mass ratio of 10:20:5:70.

[0028] The feed additive of this example is suitable for laying hens and has obvious application effect when used as feed.

[0029] The feed additive of the example is fed to the laying hens by directly adding to the feed. 80 Jingfen No. 1 laying hens of 42 weeks old (body weight 1.77±0.16 kg, egg laying rate 90.12±3.61%) are selected and divided into 4 groups, 20 hens in each group. The health control group and test groups I, II (salpingitis model group) are fed with the basic diet, and the test group III is fed with the basic diet with 0.03% of the feed additive. The laying hens are fed for 6 weeks. First, the laying hens are fed with the basic diet with or without the feed additive for 4 weeks. Then, the test groups I, II and III are constructed into salpingitis inflammation model by injecting 1 mL / hen of the modeling agent (8 mg / kg BW LPS+25% phenol paste (1:1) mixture) into the everted uterine part of the oviduct by using the artificial insemination method with the chicken insemination tube. Then, the test group II is added with 670 mg / kg of amoxicillin soluble powder in the basic diet for 1 week, and the observation is continued for 1 week after the drug is stopped. The egg laying of the laying hens is recorded every day in the unit of repetition, and the average egg laying rate of the laying hens is calculated. The blood of the laying hens is collected from the underwing vein on the 8th day after the drug is taken to detect the inflammatory factors. The results are shown in Tables 1-2.

[0030] Table 1. Effect of adding the additive in the feed on the average egg laying rate of the laying hens with salpingitis

[0031]

[0032] Note: The difference is significant (P<0.05) if the same column has different letters. The following is the same.

[0033] The results in Table 1 show that before the salpingitis model is established, there is no significant difference in the average egg laying rate of the laying hens in each group. After the salpingitis model is established, the feed additive of the application can improve the decrease of the average egg laying rate caused by the drug taking period and the salpingitis after the drug is taken. Compared with the test group I, the average egg laying rate in the drug taking period is increased by 39.65%, and the average egg laying rate after the drug is taken is increased by 51.35%, which is better than the result of the drug feeding group. The above results show that the additive of the example has the effect of replacing the drug feeding to relieve the decrease of the egg laying performance caused by the salpingitis by directly adding to the feed to feed the laying hens, and the relieving effect is better than that of the drug feeding.

[0034] The results in Table 2 show that compared with the health control group, the test group I significantly increases the levels of IL-6, IL-8, TNF-α and IFN-γ in the serum. Compared with the test group I, the feed additive of the application can significantly reduce the levels of IL-6, IL-8, TNF-α and IFN-γ in the serum of the laying hens, and there is no significant difference compared with the test group II. The above results show that the additive of the example has the effect of replacing the drug feeding to relieve the increase of the inflammatory factors caused by the salpingitis by directly adding to the feed to feed the laying hens.

[0035] Table 2. Changes of the content of the serum cell inflammatory factors of the laying hens (pg / mL)

[0036]

[0037]

[0038] Example 2:

[0039] The feed additive used in this example is prepared by mixing uniformly protocatechuic aldehyde, benzoylpaeoniflorin, sterol yeast culture and lactobacillus reuteri postbiotic at a mass ratio of 12:18:10:60.

[0040] The feed additive of this example is added to the egg hen hepatocyte culture medium, which has the effect of improving the fat metabolism capacity of egg hens.

[0041] Take the egg hen hepatocyte test as an example. The experimental groups are divided into: a blank group, 0.5, 1, 3, 4, 8, 16 μmol / L of the additive group, each group has 6 replicates. The concentration of chicken hepatoma cells (LMH cells) is 1×10 5 / mL, inoculated in 96-well plates, 100 μL / well, placed in a 37℃ incubator containing 5% CO2. After 24h of culture, the cell proliferation activity was detected by CCK8 kit. The results are shown in Table 3.

[0042] Table 3 shows that with the increase of the additive concentration of the present application, the survival rate of LMH cells shows a trend of first increasing and then decreasing, and the cell survival rate of the 8 μmol / L additive group is the highest. Compared with the blank group, adding different levels of the additive has no significant effect on the cell survival rate.

[0043] Table 3. Effect of the additive on the toxicity of LMH cells

[0044]

[0045] The experiment is divided into three groups, namely the control group, the fatty liver model group (test group I), and the 8 μmol / L additive group (test group II), each group has 6 replicates. LMH cells are inoculated in 6-well cell culture plates at a concentration of 5×10 5 / mL, and cultured in cell culture medium with or without the additive for 24h. Then, the test group I and the test group II (the control group is treated with 10% BSA) are treated with 1mM oleic acid / palmitic acid (2:1), and after 24h of modeling, the cells are collected and the content of triglyceride in LMH cells is detected according to the kit instructions. The results are shown in Table 4.

[0046] The results of Table 4 show that compared with the control group, the test group I significantly increased the content of triglyceride in cells, which indicated that the fatty liver model of LMH cells was successfully constructed; compared with the test group I, the additive group (test group II) could significantly reduce the content of triglyceride in LMH cells caused by fatty acid mixture. The above results showed that the additive in this example had the effect of reducing the content of triglyceride in fatty degeneration LMH cells by treating liver cells with cell culture medium.

[0047] Table 4. Effect of the additive on fatty metabolism of LMH cells

[0048]

[0049] Example 3:

[0050] The feed additive used in this example was prepared by mixing uniformly protocatechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and lactobacillus reuteri postbiotic at a mass ratio of 10:20:5:65.

[0051] The feed additive in this example was used in the form of feed suitable for laying hens, and the application effect was obvious.

[0052] Select 26-week-old Jingfen No. 6 laying hens (body weight 1.55±0.12 kg, egg laying rate 93.75±6.33%) 384, randomly and evenly divided into 4 groups: control group, fatty liver model group (test group I), 500 mg / kg protocatechuic aldehyde group (test group II), 500 mg / kg benzoyl paeoniflorin and lactobacillus reuteri postbiotic mixture group (mass ratio 20:65, test group III), and 300 mg / kg additive group (test group IV). Each group had 6 replicates, and each replicate had 16 laying hens. The whole test period was 9 weeks, with a pre-test period of 1 week and a formal test period of 8 weeks. The control group and test group I were fed with basic diet, and test groups II, III and IV were added with protocatechuic aldehyde, benzoyl paeoniflorin and lactobacillus reuteri and its culture mixture, and the additive of the application in the basic diet. The basic diet fed in the first to fourth weeks of the test was normal diet (CP 15.89%; ME 11.21 MJ / kg), and the basic diet fed in the fifth to eighth weeks of the test was high-energy low-protein diet (CP 12.89%; ME 12.97 MJ / kg). The average egg laying rate of laying hens was calculated in units of replicates in the fifth to eighth weeks of the test, and the egg quality, serum and liver triglyceride content at the end of the eighth week of the test were detected. The results are shown in Tables 5-7.

[0053] The results in Table 5 show that the feed additive of the present application can improve the decrease of the average egg laying rate of the hens caused by the high-energy and low-protein diet in the 5th to 8th weeks of the test. Compared with the test group I, the test groups II, III and IV can significantly increase the average egg laying rate of the hens by 14.69%, 15.97% and 37.36% respectively; compared with the test groups II and III, the test group IV can significantly increase the average egg laying rate of the hens by 19.77% and 18.44% respectively. The above results show that the additive in this example has the effect of improving the decrease of the average egg laying rate of the hens caused by fatty liver syndrome when the hens are fed by the feed additive, and is superior to the effect of the mixture of the single protocatechuic aldehyde and benzoyl paeoniflorin and the probiotics of Lactobacillus reuteri.

[0054] Table 5. Effect of the addition of the additive on the egg laying performance of the hens

[0055]

[0056] The results in Table 6 show that the feed additive of the present application can significantly increase the eggshell strength of the eggs compared with the control group, and there is no significant difference in other egg quality indicators; compared with the test group I, the test group IV can significantly increase the egg white height of the eggs by 15.40%, the Haugh unit by 12.24%, the yolk color by 24.20% and the eggshell strength by 8.11%; compared with the test groups II and III, the test group IV can significantly increase the egg white height of the eggs by 5.52% and 7.07%, the Haugh unit by 6.38% and 5.31% and the eggshell strength by 6.07% and 4.88% respectively. The above results show that the additive in this example has the effect of improving the decrease of the egg quality of the hens caused by fatty liver syndrome when the hens are fed by the feed additive, and is superior to the effect of the mixture of the single protocatechuic aldehyde and benzoyl paeoniflorin and the probiotics of Lactobacillus reuteri.

[0057] Table 6. Effect of the addition of the additive on the egg quality of the hens

[0058]

[0059] The results in Table 7 show that the feed additive of the present application can significantly reduce the triglyceride content in the serum by 27.59% compared with the control group; compared with the test group I, the test group IV can significantly reduce the triglyceride content in the serum by 61.84% and the triglyceride content in the liver by 75.00%; compared with the test groups II and III, the test group IV can significantly increase the triglyceride content in the serum by 31.54% and 30.61% and the triglyceride content in the liver by 33.33% and 27.27% respectively. The above results show that the additive in this example has the effect of improving the fatty metabolism disorder of the hens caused by fatty liver syndrome when the hens are fed by the feed additive, and is superior to the effect of the mixture of the single protocatechuic aldehyde and benzoyl paeoniflorin and the probiotics of Lactobacillus reuteri.

[0060] Table 7. Effects of adding the present additive on fat metabolism of laying hens

[0061]

[0062] Example 4:

[0063] The feed additive used in the present example was prepared by mixing uniformly protocatechuic aldehyde, benzoylpaeoniflorin, sterol yeast culture and Lactobacillus reuteri postbiotic at a mass ratio of 20:15:10:55.

[0064] The feed additive of the present example was used to inhibit pathogenic bacteria in the intestinal cavity of laying hens when added to bacterial culture medium, and the application effect was obvious.

[0065] Oxford cup method was used to measure the inhibition zone diameters of the feed additive of the present example on chicken intestinal salmonella, E. coli O78 and Clostridium perfringens (CVCC2030 strain) respectively, and to evaluate its bacteriostatic effect. Each pathogenic bacteria was grouped according to the following grouping method, and each treatment group was as follows: blank group (normal saline), antibiotic (enramycin: 0.1 μL / mL) treatment group, different gradient feed additive groups (0.2 g / mL, 0.1 g / mL, 0.05 g / mL, 0.025 g / mL, 0.0125 g / mL), each treatment group had 3 replicates. LB solid culture plates and semi-solid culture medium were prepared, 100 μL of E. coli and salmonella (1×10 6 cfu / mL) were inoculated into the LB semi-solid culture medium respectively, the medium was shaken and poured onto the LB solid culture plate, then the oxford cups were placed uniformly, after solidification, the oxford cups were taken out and 30 μL of each treatment solution was added to the ring hole, and placed in a 37℃ constant temperature incubator for 24 hours. Meat medium was prepared, and the corresponding solid culture plates and semi-solid culture medium were prepared, 100 μL of Clostridium perfringens (1×10 6 cfu / mL) was inoculated into the meat semi-solid culture medium, the medium was shaken and poured onto the meat solid culture plate, then the oxford cups were placed uniformly, after solidification, the oxford cups were taken out and 30 μL of each treatment solution was added to the ring hole, and placed in a 37℃ constant temperature incubator for 24 hours. A ruler with an accuracy of 0.01 cm was used to measure the inhibition zone diameter, and the specific results are shown in Table 8:

[0066] Table 8. Bacteriostatic effect of the feed additive of the present example on several avian pathogenic bacteria

[0067]

[0068]

[0069] Note: “—” indicates that the inhibition zone is <1 cm, and there is no bacteriostatic effect. The dose gradient in the table is the dose gradient of the feed additive of the present example.

[0070] The results of Table 8 show that the feed additive of this example has good bacteriostatic effect on avian E. coli, Salmonella and Clostridium perfringens, especially the largest diameter of the inhibition zone for Salmonella, indicating that it has obvious inhibitory effect on Salmonella enteritidis. In addition, the bacteriostatic effect of the feed additive of this example on these several avian pathogenic bacteria is basically equivalent to that of enramycin.

[0071] Example 5:

[0072] The feed additive used in this example is prepared by mixing uniformly protocatechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and Lactobacillus reuteri postbiotic at a mass ratio of 15:18:7:60.

[0073] The feed additive of this example is suitable for laying hens in the form of feed and has obvious application effect.

[0074] Select 270 Jingfen No. 6 laying hens of 26 weeks old (body weight 1.55±0.12 kg, egg laying rate 93.75±6.33%), and randomly divide them into 3 groups: control group, enteritis model group, enteritis model + 300 mg / kg feed additive group of this example. Each group has 6 replicates, and each replicate has 15 laying hens. The whole test period is 5 weeks, including 1 week of pre-test and 4 weeks of formal test. The control group and the enteritis model group are fed with the basic diet, and the enteritis model + 300 mg / kg feed additive group of this example is fed with the basic diet added with 300 mg / kg feed additive of this example. From the 3rd week of the formal test, spray Clostridium perfringens (dose 1×10 8 cfu / g feed) into the diet of the enteritis model group and the enteritis model + 300 mg / kg feed additive group of this example every day, and spray the same volume of bouillon medium into the diet of the control group. At the end of the test, select 1 healthy laying hen with uniform body weight from each replicate for subcutaneous vein blood sampling under anesthesia, and take liver, spleen, thymus and ileum tissues for detection and analysis. The data results are shown in Tables 9, 10, 11 and 12.

[0075] Table 9. Effect of the feed additive of this example on organ index of laying hens with enteritis, g / kg

[0076]

[0077] As shown in Table 9, Clostridium perfringens infection causes hepatomegaly and splenomegaly in laying hens, and the addition of the feed additive of this example in the diet can alleviate the hepatomegaly and splenomegaly caused by Clostridium perfringens infection.

[0078] Table 10. Effect of the feed additive of this example on blood biochemical indicators of laying hens with enteritis

[0079]

[0080] As shown in Table 10, Clostridium perfringens infection caused the increase of serum total bilirubin (TB), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), and uric acid (UA) of laying hens, which caused liver damage, which was consistent with the fact that Clostridium perfringens infection caused the liver enlargement of laying hens shown in Table 9. The feed additive of the present example could alleviate the increase of serum TB, AST, GGT, and UA of laying hens caused by Clostridium perfringens infection, indicating that the feed additive of the present example had a good protective effect on the health of the liver. In addition, Clostridium perfringens infection up-regulated the content of serum glucose (GLU) of laying hens, and the glucose synthesis pathway was activated to cope with the stimulation of stressors; the feed additive of the present example could alleviate the increase of serum glucose (GLU) content of laying hens caused by Clostridium perfringens infection, and further alleviate the stress response of the body.

[0081] Table 11. Effect of the feed additive of the present example on ileum gene expression of laying hens with enteritis

[0082]

[0083] As shown in Table 11, the transcription levels of pro-inflammatory cytokines such as IL-1β, IL-8, and TNF-α were significantly up-regulated in the enteritis model group; the expression of anti-inflammatory cytokines such as IL-10 was also up-regulated, but the transcription level of TGF-β was down-regulated; in addition, the expression level of intestinal tight junction protein occludin was significantly down-regulated, indicating that Clostridium perfringens infection caused inflammatory damage to the intestines of laying hens. The addition of the feed additive of the present example in the diet could alleviate the up-regulation of the transcription levels of IL-1β, IL-8, TNF-α, IL-10, and the down-regulation of the expression level of occludin caused by Clostridium perfringens infection, indicating that the feed additive of the present example could well alleviate the inflammatory damage to the intestines of laying hens caused by Clostridium perfringens infection.

[0084] Table 12. Effect of the feed additive of the present example on serum DAO and D-xylose content of laying hens with enteritis

[0085]

[0086] Diamine oxidase (DAO) is normally distributed in the intestinal mucosa, and when the mucosa is damaged, it enters the blood circulation. As shown in Table 12, the intestinal mucosa of laying hens was damaged under the enteritis model, which could be alleviated by the feed additive of the present example. In addition, D-xylose can be absorbed into the blood by the intestines, but cannot be utilized by the body, so the higher the content of D-xylose in the blood, the better the absorption function of the intestines. As shown in Table 12, the absorption function of the intestines was impaired under the enteritis model, and the feed additive of the present example could restore the absorption function of the intestines under the enteritis model.

[0087] In summary, the results of the above examples, the addition of the feed additive in the diet can improve the intestinal absorption function of laying hens, repair the intestinal inflammatory damage caused by Clostridium perfringens infection, and has a good protective effect on the liver and intestinal health of laying hens.

[0088] Example 6:

[0089] The feed additive used in this example is prepared by mixing uniformly 16:12:10:62 of protocatechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and Lactobacillus reuteri postbiotic according to the mass ratio.

[0090] The feed additive of this example is suitable for egg ducks and has obvious application effect.

[0091] Select 18-week-old Jingjiang Ma duck (body weight 1.25±0.12 kg, egg laying rate 72.67±6.33%) 270, randomly divided into 3 groups: control group, intestinal inflammation model group, intestinal inflammation model+500mg / kg feed additive group. Each group has 6 replicates, and each replicate has 15 egg ducks. The whole test period is 5 weeks, the pre-test period is 1 week, and the formal test is 4 weeks. The control group and the intestinal inflammation model group are fed with the basic diet, and the egg ducks in the intestinal inflammation model+500mg / kg feed additive group are fed with the basic diet added with 500mg / kg feed additive group. From the 3rd week of the formal test, spray Clostridium perfringens (dose 1×10 8 cfu / g feed) into the diet of the egg ducks in the intestinal inflammation model group and the intestinal inflammation model+500mg / kg feed additive group every day, and spray the same volume of broth medium into the diet of the control group. At the end of the test, select 1 healthy egg duck with uniform body weight from each replicate for subcutaneous vein blood sampling, and anaesthetize and slaughter to take the intestinal tissue for detection and analysis. The data results are shown in Tables 13, 14 and 15.

[0092] Table 13. Effect of the feed additive of this example on serum biochemical indicators of egg ducks with intestinal inflammation

[0093]

[0094] As shown in Table 13, Clostridium perfringens infection can cause the increase of serum TB, glutamic-oxalacetic transaminase (ALT) and alkaline phosphatase (ALP) contents, and has a negative impact on the liver of egg ducks. The addition of the feed additive in the diet can alleviate the abnormal changes of serum biochemical indicators of egg ducks caused by Clostridium perfringens infection, and may have a protective effect on the liver health of egg ducks.

[0095] Table 14. Effect of the feed additive of this example on serum DAO, D-xylose and LYZ of egg ducks with intestinal inflammation

[0096]

[0097] As shown in Table 14, the infection of C. perfringens caused the increase of serum DAO content and the decrease of serum lysozyme (LYZ) content, indicating that the infection of C. perfringens broke the immune function of laying ducks and caused intestinal injury. The addition of the feed additive in the diet could alleviate the abnormal changes of serum DAO and LYZ contents of laying ducks caused by the infection of C. perfringens and improve the immune function of laying ducks.

[0098] Table 15. Effects of the feed additive in the example on the ileum gene expression of laying ducks with enteritis

[0099]

[0100] As shown in Table 15, the infection of C. perfringens caused the up-regulation of the transcription levels of pro-inflammatory cytokines IL-1β and IFN-γ and the down-regulation of the mRNA levels of Mucin-2 and water channel protein (AQP3) in the ileum of laying ducks, indicating that the infection of C. perfringens caused intestinal inflammatory injury of laying ducks, which was consistent with the results shown in Table 14. The addition of the feed additive in the diet could alleviate the up-regulation of IL-1β and IFN-γ and the down-regulation of Mucin-2 and AQP3 caused by the infection of C. perfringens, and further alleviate the intestinal inflammatory injury of laying ducks.

[0101] According to the results of the example, it can be known that the addition of the feed additive in the diet has a good protective effect on the intestinal inflammatory injury of laying ducks caused by the infection of C. perfringens.

Claims

1. A feed additive, characterized in that: The raw materials include proto-catechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and lactobacillus reuteri postbiotic; The mass ratio of the proto-catechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and lactobacillus reuteri postbiotic is 10-20:10-20:5-10:50-75; The sterol yeast culture is Kluyveromyces marxianus; The lactobacillus reuteri postbiotic is obtained by a method comprising the following steps: inoculating lactobacillus reuteri into a culture medium containing poultry intestinal mucosa powder, culturing under anaerobic conditions, adding maltodextrin into the culture solution for adsorption after the culturing is completed, and spray drying to obtain the lactobacillus reuteri postbiotic. The poultry intestinal mucosa powder is prepared as follows: after poultry is slaughtered, the intestinal tract is cleaned and the intestinal mucosa is scraped, and then the intestinal mucosa is sterilized, frozen with liquid nitrogen and ground to obtain the poultry intestinal mucosa powder.

2. The method of producing a feed additive according to claim 1, characterized in that: The method comprises the following steps: mixing the proto-catechuic aldehyde, benzoyl paeoniflorin, sterol yeast culture and lactobacillus reuteri postbiotic to obtain the feed additive.

3. Use of the feed additive according to claim 1 for the preparation of a product, characterized in that: The product is at least one of the following products: a product for preventing and treating fatty liver syndrome of laying hens, a product for preventing and treating enterotoxism syndrome of laying hens, a product for preventing and treating salpingitis of laying hens, a product for promoting reproductive health of laying hens, and a product for improving egg-laying performance of laying hens; and the product comprises feed and medicine.

4. A product characterized by: The product contains the feed additive of claim 1, and is at least one of the following products: a product for preventing and treating fatty liver syndrome of laying hens, a product for preventing and treating enterotoxism syndrome of laying hens, a product for preventing and treating salpingitis of laying hens, a product for promoting reproductive health of laying hens, and a product for improving egg-laying performance of laying hens; and the product comprises feed and medicine.

Images