Feed additive for preventing goose gout based on bacterium-enzyme synergistic targeted release as well as preparation method and application of feed additive

Abstract

The invention relates to the technical field of feed additives, in particular to a feed additive for preventing goose gout based on bacterium-enzyme synergistic targeted release as well as a preparation method and application of the feed additive. The invention provides a feed additive for preventing goose gout based on bacterium-enzyme synergistic targeted release, which comprises the following components in parts by weight: 5-10 parts of enveloped tributyrin and 5-10 parts of an enzyme-producing symbiotic bacterium composition, the enzyme-producing symbiotic bacterium composition comprises a fermented product obtained by carrying out symbiotic fermentation on pediococcus pentosaceus SMM914 and bacillus subtilis. In the formula of the feed additive, the slow-release characteristic of the enveloped tributyrin is utilized to ensure that the enveloped tributyrin and the enzyme-producing symbiotic bacterium compound synchronously reach the rear section of the intestinal tract, the butyric acid is efficiently utilized, targeted positioning release is realized, and the butyric acid can be continuously released to achieve a stable relieving or treating effect.

Description

Technical Field

[0001] This invention relates to the field of feed additive technology, specifically to a feed additive for preventing gout in geese based on the synergistic targeted release of bacteria and enzymes, its preparation method, and its application. Background Technology

[0002] Goose goat's disease is caused by a disorder of uric acid metabolism, characterized by abnormally high blood uric acid levels, leading to hyperuricemia, which then deposits as urate crystals on the surfaces of joints, thoracic and abdominal cavities, and various organs. Studies have shown that the pathogenesis of goose goat's disease involves significant impairment of the intestinal barrier function and a systemic inflammatory response. When the gut microbiota is imbalanced, the number of opportunistic pathogens increases while the number of beneficial bacteria decreases, leading to damage to the integrity of the intestinal mucosal barrier and increased intestinal permeability. This allows endotoxins and other inflammatory factors to more easily enter the bloodstream, triggering a systemic inflammatory response. This inflammatory state further damages kidney function and reduces uric acid excretion, creating a vicious cycle.

[0003] Butyrate, as the gut's preferred energy source, offers multiple benefits for maintaining gut health. Studies have found that butyrate can rapidly repair damaged intestines, improve nutrient absorption, and enhance gut immunity. At the molecular level, butyrate can inhibit the expression of uric acid reabsorption protein GLUT9 mRNA while promoting the expression of uric acid excretion proteins OAT1, OAT3, and ABCG2 mRNA, thereby effectively reducing serum uric acid levels. Furthermore, butyrate can inhibit the production of inflammatory factors following urate stimulation and the activation of the NLRP3 inflammasome pathway, thus alleviating systemic inflammatory responses.

[0004] However, the application of conventional butyrate preparations has significant limitations. First, uncoated tricresyl triglycerides, after entering the digestive tract, are rapidly decomposed by lipases mainly in the anterior small intestine, leading to premature release and absorption of butyrate. Second, ordinary sodium butyrate has a distinctive fatty odor, is highly irritating, and is hygroscopic, resulting in significant losses in the poultry digestive tract and preventing it from effectively reaching the hindgut to exert its effects, thus limiting its widespread use in animal husbandry. Summary of the Invention

[0005] The present invention aims to overcome the limitations of butyric acid application in the prior art by providing a feed additive for preventing gout in geese based on synergistic targeted release of bacteria and enzymes, as well as its preparation method and application, to overcome the above-mentioned defects.

[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a feed additive for preventing gout in geese based on the synergistic targeted release of bacteria and enzymes, comprising, by weight, 5-10 parts coated glyceryl tartrate and 5-10 parts an enzyme-producing symbiotic composition; the enzyme-producing symbiotic composition comprises a ferment obtained by symbiotic fermentation of Pediococcus pentosaceus SMM914 and Bacillus subtilis.

[0007] This invention encapsulates tributylate, allowing it to be released into the posterior intestinal tract, thus increasing the body's utilization of butyric acid. Furthermore, in the posterior intestinal tract, a highly active, specific lipase produced by the enzyme-producing symbiotic bacterial composition catalyzes the hydrolysis of tributylate, releasing butyric acid and glycerol in situ. This enhances the complete absorption of butyric acid in the intestine, avoiding its loss during gastrointestinal motility. Simultaneously, the released glycerol serves as a substrate for the proliferation of the enzyme-producing symbiotic bacterial composition, promoting its amplification and competitively inhibiting pathogenic bacteria. This constructs a self-amplifying and positively circulating, self-operating, bacteria-guided, enzyme-controlled, targeted release system in the posterior intestinal tract. By continuously enhancing intestinal barrier function and reducing endotoxin translocation and its associated systemic inflammation, this system can target a key trigger for hyperuricemia and gout, providing a novel strategy for achieving long-term, stable remission of gout.

[0008] The core inventiveness of this invention lies in constructing a self-sustaining "bacterial-guided enzyme-controlled targeted release" system. Utilizing the sustained-release properties of the encapsulated tricariin, it ensures that the tricariin and the enzyme-producing symbiotic complex arrive at the lower part of the intestine simultaneously. Subsequently, under the influence of the intestinal environment, the bacteria in the enzyme-producing symbiotic complex colonize and exert their effects, causing the tricariin to be continuously released into the intestine. This achieves the goal of efficiently utilizing butyric acid and realizing targeted release, while also continuously releasing butyric acid to achieve a stable relief or therapeutic effect.

[0009] Preferably, the release time of the coated tributylate is ≥6 h.

[0010] Preferably, the mass ratio of the coated glyceryl tartrate and the enzyme-producing symbiotic bacteria composition is (0.8~1.2):(0.8~1.2).

[0011] Preferably, the enzyme-producing symbiotic composition comprises a ferment obtained by symbiotic fermentation of Pediococcus pentosaceus SMM914, Bacillus subtilis, chicory, gardenia, and hawthorn.

[0012] Preferably, the Pediococcus pentosaceus ( Pediococcus Pentosaceus SMM914 is deposited at the China General Microbiological Culture Collection Center, with accession number CGMCC:20160.

[0013] Preferably, the coated tributylate is tributylate and a membrane material coating the surface of the tributylate, wherein the membrane material includes sodium alginate, ethyl cellulose, hydrophobic beeswax and shellac.

[0014] Preferably, the content of the glyceryl tributyrate is 30-50 wt%, based on the mass of the coated glyceryl tributyrate.

[0015] Preferably, the membrane material comprises, by weight, 3-8 parts sodium alginate, 30-40 parts ethyl cellulose, 50-75 parts hydrophobic beeswax and 7-15 parts shellac.

[0016] Preferably, the lipase activity of the enzyme-producing symbiotic composition is ≥1.5 U / g; and / or, the Bacillus subtilis is Bacillus subtilis YHK11.

[0017] The inventors screened specific Bacillus subtilis and Pediococcus pentosaceus SMM914 to produce strain synergy, which drives the self-operation of the "bacterial-guided enzyme-controlled targeted release" system, ensuring the complete and stable release of butyric acid.

[0018] Preferably, the enzyme-producing symbiotic composition is prepared by inoculating Pediococcus pentosaceus SMM914 and Bacillus subtilis into a fermentation medium and fermenting.

[0019] Preferably, the fermentation conditions are: fermentation at 30~40℃ for 36~60 h.

[0020] Preferably, the mass ratio of Pediococcus pentosaceus SMM914 to Bacillus subtilis is (0.8~1.2):(0.8~1.2).

[0021] This invention also provides a method for preparing a feed additive for preventing gout in geese based on synergistic targeted release of microbial enzymes, comprising: S1. Pediococcus pentosaceus SMM914 and Bacillus subtilis were inoculated into a fermentation medium and fermented to obtain an enzyme-producing symbiotic composition. S2. A membrane material solution is prepared by mixing sodium alginate, ethyl cellulose, hydrophobic beeswax and shellac. The membrane material solution is then sprayed onto the surface of glyceryl tributylate to obtain coated glyceryl tributylate. S3. A feed additive is obtained by combining a mixed enzyme-producing symbiotic bacteria composition with coated tricresyl ester.

[0022] The present invention also provides a gout prevention feed for geese, comprising a feed additive based on the synergistic targeted release of bacteria and enzymes to prevent gout in geese, and the feed.

[0023] Preferably, the amount of the feed additive is 350~550 mg / kg.

[0024] This invention also provides the application of a feed additive based on the synergistic targeted release of bacteria and enzymes to prevent gout in the preparation of gout-preventing feed for geese.

[0025] Therefore, the present invention has the following beneficial effects: (1) In the feed additive formulation of the present invention, the sustained-release properties of coated tricresyl ester are used to ensure that it reaches the lower part of the intestine synchronously with the enzyme-producing symbiotic bacteria complex, efficiently utilizes butyric acid, achieves targeted release, and can continuously release butyric acid to achieve stable relief or treatment effects.

[0026] (2) In the feed additive formulation of the present invention, the highly active and specific lipase produced by the metabolism of the enzyme-producing symbiotic bacteria composition is used to catalyze the hydrolysis of tributyric acid glyceride to release butyric acid and glycerol in situ; in this way, the complete absorption of butyric acid by the intestine can be increased, and the loss of butyric acid during the gastrointestinal motility process can be avoided.

[0027] (3) The present invention constructs a feed additive formula with a self-sustaining “bacterial-guided enzyme-controlled targeted release” system, which can achieve the effect of preventing gout in geese. Attached Figure Description

[0028] Figure 1 Anatomical diagram of meat geese in the 13-day-old model control group.

[0029] Figure 2 Pathological sections of liver and kidney tissues from 13-day-old meat geese. Detailed Implementation

[0030] The present invention will be further described below with reference to specific embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only some, not all, of the embodiments of the present invention. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0031] In this section, Pediococcus pentosaceus ( Pediococcus Pentosaceus SMM914 is deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC:20160; it has been published in CN111961625A. Bacillus subtilis YHK11 was donated by Shandong Yihao Biotechnology Co., Ltd. Bacillus licheniformis YHD2 was donated by Shandong Yihao Biotechnology Co., Ltd. Bacillus coagulans NSL1204 was donated by Qingdao Nuosen Biotechnology Co., Ltd. Saccharomyces cerevisiae was donated by Shandong Yihao Biotechnology Co., Ltd.

[0032]

Example

[0033] Through extensive creative work, the inventors screened specific strains from different types of bacteria that exhibit significant synergistic effects with *Pediococcus pentosaceus* SMM914. The screening criteria are as follows: after co-fermentation with SMM914, the enzyme-producing symbiotic composition not only needs to possess high absolute enzyme activity (≥ 1.5 U / g), but more importantly, it must demonstrate a significant synergistic effect, i.e., the lipase activity increase rate must be at least 30% higher than the sum of the enzyme activities of the two strains fermenting alone. Only strain combinations that meet these two conditions are considered effective combinations capable of achieving the objectives of this invention.

[0034] The results of the lipase activity assay are shown in Table 1 below.

[0035] Table 1. Symbiotic fermentation activities of different strains with Pediococcus pentosaceus SMM914

[0036] Analysis of Table 1 shows that the enzyme activity after fermentation by *Saccharomyces cerevisiae* and *Pediococcus pentosaceus* SMM914 was less than 30%, indicating that the combination of *Saccharomyces cerevisiae* and *Pediococcus pentosaceus* SMM914 was ineffective and unsuitable as the enzyme-producing symbiotic composition in this invention. In the following experiments, only the other three combinations were used for further evaluation.

[0037] Example 1 S1. Activate Pediococcus pentosacchariformis SMM914, then inoculate Pediococcus pentosacchariformis SMM914 and Bacillus subtilis YHK11 into the fermentation medium at a mass ratio of 1:1, and ferment at 37°C for 48 h to obtain the enzyme-producing symbiotic composition.

[0038] S2. By weight, 5 parts sodium alginate, 35 parts ethyl cellulose, 60 parts hydrophobic beeswax, and 10 parts shellac are weighed and mixed to prepare a membrane material solution. Subsequently, the membrane material solution and glyceryl tributylate are mixed at a mass ratio of 1:1, and the membrane material solution is sprayed onto the surface of glyceryl tributylate to obtain a coated glyceryl tributylate with a glyceryl tributylate content of 50 wt%.

[0039] S3. Weigh 5 parts by weight of the S1 enzyme-producing symbiotic bacterial composition and 5 parts by weight of the S2 coated tricresyl ester to obtain a feed additive for preventing gout in geese based on the synergistic targeted release of bacteria and enzymes.

[0040] Comparative Example 1 (uncoated tributyric acid glyceride) Activate Pediococcus pentosacchariformis SMM914, then inoculate Pediococcus pentosacchariformis SMM914 and Bacillus subtilis YHK11 into the fermentation medium at a mass ratio of 1:1, and ferment at 37°C for 48 h to obtain an enzyme-producing symbiotic composition, which is the feed additive.

[0041] Comparative Example 2 This comparative example is basically the same as Example 1, except that in S1, Bacillus subtilis YHK11 is replaced with an equal mass of Bacillus licheniformis YHD2, thus obtaining the feed additive.

[0042] Comparative Example 3 This comparative example is basically the same as Example 1, except that in S1, Bacillus subtilis YHK11 is replaced with an equal mass of Bacillus coagulans NSL1204, thus obtaining the feed additive.

[0043] [Performance Testing] 1. Gastrointestinal dissolution test Artificial gastric and intestinal fluids were prepared in accordance with the requirements of the 2020 edition of the Chinese Veterinary Pharmacopoeia.

[0044] Artificial gastric fluid operation procedure: Take 0.2 g of the coated tributylate ester prepared in Example 1 (accurate to 0.0002 g), place it in a dissolution vessel, and use a rotating basket. The apparatus should be designed according to Method 1 (basket method) of Part I, 0931, of the 2020 edition of the Chinese Veterinary Pharmacopoeia. Add 400 mL of artificial gastric fluid, set the temperature to 38℃, and the rotation speed to 100 r / min. After rotating for 0.5 h, 1 h, 1.5 h, and 2 h, the residue content should be determined using high-performance liquid chromatography (HPLC). After the 2 h gastric fluid stage, transfer the entire rotating basket to a new dissolution vessel, rinse the basket three times with 10 mL of 37℃ physiological saline, add 400 mL of artificial intestinal fluid, set the temperature to 38℃, and the rotation speed to 100 r / min. After rotating for 1 h, 2 h, 3 h, and 4 h, the residue content should be determined using HPLC.

[0045] The test results recorded in artificial gastric fluid and human intestinal fluid are shown in Table 2.

[0046] Table 2 Release rates (%) in artificial gastric and intestinal fluids

[0047] As shown in Table 2, the release data indicates that the coated tributyrate glyceride achieves a good sustained-release effect. It is almost completely released in the stomach, but more than 95% is released in the intestines within approximately 6 hours. This facilitates the targeted release of butyrate, allowing it to act precisely on the intestines and thus alleviate the symptoms of gout.

[0048] 2. Modeling Four hundred one-day-old Sanhua geese (half male and half female) were randomly divided into two groups according to body weight, including one control group and one model control group. Each group had 10 replicates, with each replicate containing 20 geese. The control group was fed a basal diet (20.10% crude protein, 1.98% calcium) throughout the experiment, while the model control group was fed a high-protein, high-calcium diet (MC, 24.25% crude protein, 3.78% calcium; detailed formula is shown in Table 3). This model method was based on the literature published by Professor Yang Lin's team at South China Agricultural University (Study on the effects of fructooligosaccharides, xylooligosaccharides, and Lactobacillus rhamnosus on hyperuricemic Magang geese). The experiment lasted for 13 days, with all geese kept under uniform environmental conditions and given free access to feed and water. At 13 days of age, two geese from each replicate were selected for fasting blood sampling to determine serum uric acid and creatinine levels, and liver and kidney tissue samples were also collected. Samples were fixed in 4% paraformaldehyde, embedded in paraffin, sectioned, and then stained with H&E to observe changes in tissue structure. Subsequently, two experienced pathologists performed pathological scoring under double-blind conditions to assess the potential damage to organs caused by the high-protein, high-calcium diet. Serum uric acid and creatinine levels were measured using appropriate commercially available test kits, strictly following the instructions provided.

[0049] Table 3. Feed formulation and nutrient levels (air-dried basis, %)

[0050] Note: 1 represents the following per kilogram of feed: Vitamin A 40,000,000 IU, Vitamin D3 10,000,000 IU, Nicotinamide 200,000 mg, Vitamin E 100,000 mg, D-Pantothenic Acid 60,000 mg, Vitamin B2 30,000 mg, Vitamin K3 20,000 mg, Vitamin B6 20,000 mg, Vitamin B6 0.5 ... 12 12100mg, VB1 10000mg, folic acid 5000mg, biotin 500g, ethoxyquin 500mg. 2. Provides per kilogram of feed: manganese (120-130g / kg), ferrous iron (100-110g / kg), copper (8-12g / kg), cobalt (0.4-0.6g / kg), selenium (0.3-0.5g / kg), moisture ≤3%. Raw material composition: sulfate, sodium selenite, calcium iodate, carrier: calcium carbonate. 3. Nutritional levels are calculated values.

[0051] Table 4. Effects of high-protein, high-calcium diets on serum uric acid and creatinine levels in geese.

[0052] As shown in Table 4, compared with the control group, the serum uric acid and creatinine levels of the model control group geese were significantly increased. Their serum uric acid concentration exceeded the solubility threshold (approximately 400 μmol / L), meeting the diagnostic criteria for hyperuricemia (Xi Yumeng, Yan Junshu, Ying Shijia, et al. Effects of high-protein, high-calcium diets on the occurrence of visceral gout, renal function, and intestinal microbiota in goslings [J]. Journal of Animal Nutrition, 2019, 31(02):612-621.). During the experiment, 13-day-old Sanhua geese exhibited symptoms such as lethargy, difficulty standing, persistent prone position, significantly reduced appetite, and excretion of white, watery feces. Figure 1 During the autopsy of the dead geese, it was found that the kidneys of geese with hyperuricemia were significantly enlarged, and white, viscous urate deposits could be seen oozing out when the ureters were opened.

[0053] Furthermore, pathological sections were taken from the kidneys of the meat geese in the model control group (see...). Figure 2 It can be seen that in the model control group, the kidneys and livers of meat geese showed extensive inflammatory cell infiltration accompanied by hemorrhage; the kidney cell structure was irregular, and inflammatory cell infiltration was visible. Specifically, Figure 2 In the mid-field, the liver plates are arranged radially, composed of a double layer of hepatocytes. A small number of hepatocytes show fatty degeneration (yellow arrows), with round vacuoles of varying sizes appearing in the cytoplasm; a small number of hepatocytes are edematous (blue arrows), with loose and pale-stained cytoplasm; the liver plates are arranged regularly and neatly, with no obvious dilation or compression of the hepatic sinusoids; numerous inflammatory cell infiltrations are visible around the blood vessels (red arrows). Within the field, the renal lobule consists of a large cortex and a smaller medulla. The central glomerulus in the cortex is composed of a cluster of extraglomerular mesangial cells with strongly basophilic nuclei; the renal tubules vary in size, with abundant tubular epithelial edema (blue arrows), swollen cell bodies, and loose and pale-stained cytoplasm; there is no obvious interstitial proliferation, but a small amount of interstitial vascular congestion is observed (yellow arrows).

[0054] Based on the above indicators, it can be seen that the high-calcium, high-protein diet successfully induced a gout model in geese.

[0055] 3. Synergistic effect of bacteria and enzymes in relieving gout in geese After modeling was completed at 13 days of age using the above-described method, 720 geese with gout who successfully developed the model at 14 days of age and 120 healthy control geese, totaling 840 geese, were selected for an improvement effect experiment. The geese with gout were randomly divided into 6 groups, with 6 replicates per group and 20 geese per replicate. The grouping settings are shown in Table 5: the healthy control group was fed a basal diet; the model control group consisted of geese with gout who were switched to a basal diet after 14 days of age; the remaining 4 groups (Example 1 and Comparative Examples 1-3) received different feed additives at 500 g / t added to the model control group's diet. The experiment continued until 70 days of age. Fasting blood samples were collected at 35 and 70 days of age to detect serum uric acid, creatinine, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels. At 70 days of age, serum immunoglobulins and inflammatory markers were measured, and cecal contents were collected to determine butyrate content and bacterial abundance. The geese were also weighed, and the feed conversion ratio and mortality rate were calculated. All serum indicators were determined using the corresponding commercially available kits; cecal butyrate content was analyzed by gas chromatography; bacterial counts were determined by selective culture plate counting, and the results are expressed as 1g CFU / g.

[0056] Table 5 Grouping

[0057] Table 6. Effects of additives on serum uric acid and creatinine levels in meat geese

[0058] At 35 days of age, the serum uric acid level in the Example 1 group was significantly lower than that in the model control group and comparative groups 1-3, and decreased to within the gout threshold (400 μmol / L); the serum creatinine level was not significantly different from that in the control group (reached normal level), and was significantly lower than that in the model control group and comparative groups 1-3; at the same time, the serum ALT and AST levels were also significantly lower than those in the model control group and comparative groups 1-3. The additive in Example 1 showed a synergistic effect of early kidney protection, uric acid metabolism regulation and liver damage prevention.

[0059] At 70 days of age, the serum uric acid and creatinine levels in Example 1 group were not significantly different from those in the control group, and had completely recovered to the physiological levels of healthy meat geese. Serum ALT and AST levels also remained within the normal range similar to those in the control group. All four indicators were significantly lower than those in the model control group and Comparative Examples 1-3. This demonstrates that the additive in Example 1 can significantly improve the health status of gout model meat geese from multiple dimensions, including uric acid metabolism, kidney protection, and liver repair. Its intervention effect is comprehensively superior in all comparative examples, demonstrating a significant technological advantage.

[0060] Table 7. Effects of additives on meat goose production performance

[0061] As shown in Table 7, the body weight of the control group geese at 13 days was significantly higher than that of the other groups. At 70 days of age, the body weight, feed conversion ratio, and mortality rate of the geese in Example 1 group were all better than those in Comparative Examples 1-3, and there was no significant difference compared with the control group. This indicates that the additive in Example 1 effectively improved the negative impact of gout on the production performance of geese.

[0062] Table 8. Effects of additives on serum immune and inflammatory markers in meat geese.

[0063] As shown in Table 8, the serum immunoglobulin (IgG and IgA) levels of the goose group in Example 1 were not statistically different from those in the control group, indicating that they had recovered to the normal physiological range. Simultaneously, their serum inflammatory factor (TNF-α, IL-6, and IL-1β) levels were comparable to those of the healthy control group and significantly lower than those of the model control group. In contrast, none of the comparative groups achieved the same level of improvement in either of the two indicators as Example 1. This indicates that the additive in Example 1 can effectively reverse the model-induced immunosuppression and excessive inflammation.

[0064] Table 9. Effects of different feed additives on butyrate and gut microbiota composition in the cecum of meat geese.

[0065] As shown in Table 9, the butyrate content and lactic acid bacteria count in the cecum of the goose in Example 1 reached the highest levels. The butyrate content was significantly different from the control group, while the lactic acid bacteria count showed no statistically significant difference and was significantly better than the model control group and all comparative groups. Simultaneously, the counts of Escherichia coli and Salmonella in the cecum remained at the lowest levels, comparable to the control group and significantly lower than the other groups. This indicates that the additive in Example 1 can significantly increase butyrate content, increase the abundance of beneficial bacteria, and inhibit the proliferation of pathogenic bacteria, demonstrating a remarkable effect in regulating the intestinal microecological balance.

Claims

1. A feed additive for preventing gout in geese based on synergistic targeted release of bacteriocins, characterized in that, 5-10 parts by weight of coated tributyrin and 5-10 parts by weight of enzyme-producing symbiotic bacteria composition; the enzyme-producing symbiotic bacteria composition comprises a fermentation product of Pediococcus pentosaceus SMM914 and Bacillus subtilis symbiotic fermentation.

2. The feed additive according to claim 1, c h a r a c t e r i z e d in that The release time of the coated tributyrin is ≥6 h; Preferably, the mass ratio of the coated tributyrin and the enzyme-producing symbiotic bacteria composition is (0.8-1.2):(0.8-1.2). Preferably, the enzyme-producing symbiotic bacteria composition comprises a fermentation product of Pediococcus pentosaceus SMM914, Bacillus subtilis, chicory, gardenia and hawthorn symbiotic fermentation.

3. The feed additive according to claim 1 or 2, c h a r a c t e r i z e d in that S. pentosus (P1 1 1 1 ) Pediococcus Pentosaceus SMM914 was deposited at China General Microbiological Culture Collection Center, and the deposit number is CGMCC:20160.

4. The feed additive according to claim 1, characterized in that, The coated tributyrin is tributyrin and a film material coated on the surface of the tributyrin, and the film material comprises sodium alginate, ethyl cellulose, hydrophobic beeswax and shellac; Preferably, the content of the tributyrin is 30-50 wt% based on the mass of the coated tributyrin.

5. The feed supplement according to claim 4, c h a r a c t e r i z e d in that The film material comprises 3-8 parts by weight of sodium alginate, 30-40 parts by weight of ethyl cellulose, 50-75 parts by weight of hydrophobic beeswax and 7-15 parts by weight of shellac.

6. The feed additive according to claim 1 or 2, characterized in that, The lipase activity of the enzyme-producing symbiotic bacteria composition is ≥1.5 U / g; and / or the Bacillus subtilis is Bacillus subtilis YHK11.

7. The feed supplement according to claim 6, c h a r a c t e r i z e d in that The preparation method of the enzyme-producing symbiotic bacteria composition comprises inoculating Pediococcus pentosaceus SMM914 and Bacillus subtilis into a fermentation medium and obtaining a fermentation product by fermentation. Preferably, the fermentation conditions are 30-40°C for 36-60 h. Preferably, the mass ratio of the Pediococcus pentosaceus SMM914 and the Bacillus subtilis is (0.8-1.2):(0.8-1.2).

8. The method of producing a feed additive according to any one of claims 1 to 7, characterized in that, Comprising: S1. inoculating Pediococcus pentosaceus SMM914 and Bacillus subtilis into a fermentation medium and obtaining an enzyme-producing symbiotic bacteria composition by fermentation; S2. mixing sodium alginate, ethyl cellulose, hydrophobic beeswax and shellac to obtain a film material liquid, and then spraying the film material liquid on the surface of tributyrin to obtain coated tributyrin; S3. mixing the enzyme-producing symbiotic bacteria composition and the coated tributyrin to obtain a feed additive.

9. A feed for preventing gout in geese, characterized by, Comprising the feed additive of any one of claims 1-7 or the feed additive prepared by the preparation method of claim 8, and a feed; Preferably, the dosage of the feed additive is 350-550 mg / kg.

10. The use of the feed additive of any one of claims 1-7 or the feed additive prepared by the preparation method of claim 8 in the preparation of a feed for preventing gout in geese.

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