Selenium-rich microecological preparation and application thereof in antibiotic-free breeding of meat geese

Abstract

The invention discloses a selenium-rich microecological preparation. The selenium-rich microecological preparation is prepared by the following steps: S1, activating strains; s2, preparing a selenomethionine premixed solution; s3, co-culture of bacteria and selenium; s4, forming a selenoprotein complex; s5, preparing a coating material; s6, coating with an emulsion; s7, acid-resistant layer coating; and S8, enteric activation treatment. According to different growth stages of the meat geese in the antibiotic-free breeding, a daily ration formula is directionally intervened: in the brooding period of the meat geese, the selenium-rich microecological preparation and daily ration feed are mixed in a dry mode, and conventional feeding is carried out; in the growth period of the meat geese, acidifying the selenium-rich microecological preparation, preparing the selenium-rich microecological preparation into a solution, and feeding the meat geese with the solution in the form of drinking water; in the fattening period of the meat geese, the premix containing the selenium-enriched microecological preparation is mixed with daily ration, and the meat geese are fed in an intensified mode. According to the invention, selenium-rich breeding of meat geese can be realized, economic benefits are increased, antibiotics can be replaced, and the eating safety and edible value of meat geese are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of breeding, and in particular relates to a selenium-enriched microecological preparation and application thereof in antibiotic-free breeding of meat geese. Background Art

[0002] With the rapid development of intensive livestock and poultry farming, the long-term abuse of antibiotics in feed has become a global problem.

[0003] Probiotics inhibit pathogens by regulating the balance of intestinal flora and are considered an ideal alternative to antibiotics. However, existing single-bacteria preparations have technical bottlenecks such as low colonization efficiency, survival rate <30%, and poor gastric acid tolerance. At the same time, the problem of selenium deficiency in livestock and poultry is becoming increasingly prominent. The selenium content in the diet of meat geese is insufficient, and the traditional sodium selenite supplement has low bioavailability. Summary of the invention

[0004] The purpose of the present invention is to provide a selenium-rich microecological preparation and its application in antibiotic-free breeding of meat geese to solve the technical problems raised in the above background technology.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A selenium-rich microecological preparation is prepared by the following steps:

[0007] S1. Activation of bacterial strains: freeze-dried powder of Bacillus subtilis, freeze-dried powder of Enterococcus faecalis, and freeze-dried powder of Candida utilis were taken, cultured and activated, and prepared into bacterial suspensions respectively;

[0008] Preparation of S2 selenomethionine premix: dissolve selenomethionine in 40-60℃ sterile water to prepare 40-60mg / mL selenomethionine mother solution, and sterilize with filter membrane;

[0009] S3 bacteria-selenium co-culture: the Bacillus subtilis suspension, Enterococcus faecalis suspension and Candida utilis suspension obtained in S1 are mixed according to the volume ratio to obtain a mixed bacterial suspension, 8-12% selenomethionine mother solution is added to the mixed bacterial suspension, and then an inducer is added, and the mixture is statically cultured at a temperature of 30-50°C, pH 6-6.5 and microaerobic conditions for 4-8 hours;

[0010] S4 selenoprotein complex formation: adding 0.2-0.8% chitosan solution by volume to the system after S3 culture, stirring, and obtaining selenoprotein complex;

[0011] S5 coating material preparation: preparation of water phase and oil phase;

[0012] S6 emulsion coating: the selenium-bacteria composite system is mixed with the water phase at a volume ratio of 1:2-4, and then mixed with the oil phase at a volume ratio of 1:3-5. After mixing, high pressure homogenization is performed at 30-60 MPa; after homogenization, spray drying is performed, and the inlet air temperature of the spray drying is 70-85°C, the outlet air temperature is 40-50°C, the atomization pressure is 0.4-1 MPa, and the flow rate is 5-10 L / h to obtain microcapsule particles;

[0013] S7 acid-resistant layer coating: fluidized bed coating using coating materials;

[0014] S8 enteric activation treatment: spray the activator on the outer coating layer of S7 to obtain a selenium-rich microecological preparation.

[0015] Further, in S1, the freeze-dried powder of Bacillus subtilis is dissolved in LB medium at a ratio of 1 g:10 L, and cultured at 20-40°C and 100-200 rpm for 10-18 hours; the freeze-dried powder of Enterococcus faecalis is dissolved in MRS medium at a ratio of 1 g:10 L, and cultured anaerobically at 30-40°C for 12-20 hours; the freeze-dried powder of Candida utilis is dissolved in YDP medium at a ratio of 1 g:10 L, and cultured at 20-30°C and 80-150 rpm for 20-28 hours; after the culture is completed, the bacterial sludge is collected by a continuous centrifuge, and washed with PBS buffer after collection, and concentrated to a bacterial suspension of 1-2×10^12 CFU / mL;

[0016] Further, in S3, the Bacillus subtilis suspension: the Enterococcus faecalis suspension: the Candida utilis suspension are mixed in a volume ratio of 2-4: 1-3: 0.5-1.5.

[0017] Furthermore, in S3, the synergist is 1-3% maltodextrin and 0.5-2% xylooligosaccharide in the volume of the mixed bacterial suspension.

[0018] Furthermore, in S5, the aqueous phase is prepared by dissolving 10-18% skimmed milk powder and 2-8% trehalose in deionized water; and the oil phase is prepared by dissolving 1-5% gum arabic and 1-3% glyceryl monostearate in vegetable oil.

[0019] Furthermore, in S7, the coating material is 4-6% Eudragit L100-55.

[0020] Further, in S8, the activator is 0.2-0.8% pectinase and 0.1-0.5% xylanase dry powder.

[0021] The application of selenium-rich proecological preparations in antibiotic-free breeding of meat geese, according to the different growth stages of meat geese in antibiotic-free breeding, targeted intervention diet formula: during the brooding period of meat geese, the selenium-rich proecological preparations are dry-mixed with the daily diet at a ratio of 200-300g / ton of feed and fed conventionally; during the growth period of meat geese, the selenium-rich proecological preparations are acidified and prepared into a solution, and the solution is fed to the meat geese in the form of drinking water; during the fattening period of meat geese, the premix containing selenium-rich proecological preparations is mixed with the daily diet, and the meat geese are fed with intensive feeding.

[0022] Furthermore, the acidification method of the selenium-rich microecological preparation is: compounding the selenium-rich microecological preparation with a 0.1% lactic acid solution, and preparing the mixture with water to form a 0.1-0.15% solution.

[0023] Furthermore, the premix is ​​a mixture of selenium-rich microecological preparation, selenium yeast powder, and maltodextrin-stone powder carrier.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention prepares a selenium-enriched microecological preparation by combining organic selenium source selenomethionine with Bacillus subtilis, Enterococcus faecalis and Candida utilis through capsule coating, wherein Bacillus subtilis, Enterococcus faecalis and Candida utilis are used together to synergistically enhance the absorption of selenium by meat geese, thereby realizing selenium-enriched breeding of meat geese and increasing economic benefits.

[0026] 2. The selenium-rich microecological preparation of the present invention is applied to the antibiotic-free breeding of meat geese. The various indicators of the meat geese raised with conventional antibiotics are not much different. Some indicators are higher than those raised with antibiotics. This shows that the selenium-rich microecological preparation of the present application can well replace antibiotics. When applied to the breeding of meat geese, it can reduce the use of antibiotics and improve the edible value of meat geese. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, preferred embodiments are given below to further describe the present invention in detail. However, it should be noted that many details listed in the specification are only for the purpose of enabling the reader to have a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be implemented even without these specific details.

[0028] A selenium-rich microecological preparation is prepared by the following steps:

[0029] S1 strain activation: Take the freeze-dried powder of Bacillus subtilis, dissolve it in LB medium at a ratio of 1g:10L, and shake culture at 20-40℃ and 100-200rpm for 10-18h; take the freeze-dried powder of Enterococcus faecalis, dissolve it in MRS medium at a ratio of 1g:10L, and culture it anaerobically at 30-40℃ for 12-20h; take the freeze-dried powder of Candida utilis, dissolve it in YPD medium at a ratio of 1g:10L, and shake culture it at 20-30℃ and 80-150rpm for 20-28h; after the culture is completed, use a continuous centrifuge to collect the bacterial sludge, wash it with PBS buffer after collection, and concentrate it to 1-2×10^ 12 CFU / mL bacterial suspension;

[0030] Preparation of S2 selenomethionine premix: dissolve selenomethionine in 40-60℃ sterile water to prepare 40-60mg / mL selenomethionine mother solution, and sterilize with filter membrane;

[0031] S3 bacteria-selenium co-culture: the Bacillus subtilis suspension, Enterococcus faecalis suspension and Candida utilis suspension obtained in S1 are mixed in a volume ratio of 2-4:1-3:0.5-1.5 to obtain a mixed bacterial suspension, 8-12% of selenomethionine mother solution, 1-3% of maltodextrin and 0.5-2% of oligoxylose are added to the mixed bacterial suspension, and the mixture is statically cultured at a temperature of 30-50°C, pH 6-6.5 and microaerobic conditions for 4-8 hours;

[0032] S4 selenoprotein complex formation: adding 0.2-0.8% chitosan solution by volume to the system after S3 culture, stirring, and obtaining selenoprotein complex;

[0033] Preparation of S5 coating material: 10-18% skim milk powder and 2-8% trehalose are dissolved in deionized water to prepare the water phase; 1-5% gum arabic and 1-3% glyceryl monostearate are dissolved in vegetable oil to prepare the oil phase;

[0034] S6 emulsion coating: the selenium-bacteria composite system is mixed with the water phase at a volume ratio of 1:2-4, and then mixed with the oil phase at a volume ratio of 1:3-5. After mixing, high pressure homogenization is performed at 30-60 MPa; after homogenization, spray drying is performed, and the inlet air temperature of the spray drying is 70-85°C, the outlet air temperature is 40-50°C, the atomization pressure is 0.4-1 MPa, and the flow rate is 5-10 L / h to obtain microcapsule particles;

[0035] S7 acid-resistant layer coating: fluidized bed coating using 4-6% Eudragit L100-55 ethanol solution;

[0036] S8 enteric activation treatment: spray 0.2-0.8% pectinase and 0.1-0.5% xylanase dry powder on the outer layer of S7 coating to obtain a selenium-rich microecological preparation.

[0037] The application of selenium-rich proecological preparations in antibiotic-free breeding of meat geese, according to the different growth stages of meat geese in antibiotic-free breeding, targeted intervention diet formula: during the brooding period of meat geese, the selenium-rich proecological preparations are dry-mixed with the daily diet at a ratio of 200-300g / ton of feed, and fed conventionally; during the growth period of meat geese, the selenium-rich proecological preparations are compounded with 0.1% lactic acid solution, prepared with water into 0.1-0.15% solution, and the solution is fed to the meat geese in the form of drinking water; during the fattening period of meat geese, the premix containing selenium-rich proecological preparations is mixed with the daily diet, and the meat geese are fed with intensive feeding.

[0038] The premix is ​​a mixture of selenium-rich microecological preparation, selenium yeast powder and maltodextrin-stone powder carrier.

[0039] The following is a more specific example.

[0040] Example 1

[0041] A selenium-rich microecological preparation is prepared by the following steps:

[0042] S1 strain activation: Take the freeze-dried powder of Bacillus subtilis, dissolve it in LB medium at a ratio of 1g:10L, and culture it at 37℃ and 100rpm for 12h; take the freeze-dried powder of Enterococcus faecalis, dissolve it in MRS medium at a ratio of 1g:10L, and culture it at 35℃ for 12h in anaerobically static manner; take the freeze-dried powder of Candida utilis, dissolve it in YPD medium at a ratio of 1g:10L, and culture it at 25℃ and 150rpm for 24h in shaking; after the culture is completed, use a continuous centrifuge to collect the bacterial sludge, wash it with PBS buffer after collection, and concentrate it to 1×10^ 12 CFU / mL bacterial suspension;

[0043] Preparation of S2 selenomethionine premix: Dissolve selenomethionine in 40℃ sterile water to prepare 40mg / mL selenomethionine mother solution, and sterilize with filter membrane;

[0044] S3 bacteria-selenium co-culture: the Bacillus subtilis suspension, Enterococcus faecalis suspension and Candida utilis suspension obtained in S1 were mixed in a volume ratio of 4:3:1 to obtain a mixed bacterial suspension, 12% selenomethionine mother solution, 2% maltodextrin and 1% xylo-oligosaccharide were added to the mixed bacterial suspension, and the mixture was cultured at a temperature of 50°C, pH 6 and microaerobic conditions for 8 hours;

[0045] S4 selenoprotein complex formation: add 0.2% chitosan solution by volume to the system after S3 culture, stir, and obtain selenoprotein complex;

[0046] Preparation of S5 coating material: 12% skim milk powder and 2% trehalose were dissolved in deionized water to prepare the water phase; 1% gum arabic and 1% glyceryl monostearate were dissolved in vegetable oil to prepare the oil phase;

[0047] S6 emulsion coating: The selenium-bacteria composite system was mixed with the water phase at a volume ratio of 1:3, and then mixed with the oil phase at a volume ratio of 1:4. After mixing, high-pressure homogenization was performed at 80 MPa; after homogenization, the mixture was spray-dried, and the inlet air temperature of the spray-drying was 80°C, the outlet air temperature was 45°C, the atomization pressure was 0.8 MPa, and the flow rate was 10 L / h to obtain microcapsule particles;

[0048] S7 acid-resistant layer coating: fluidized bed coating using 6% Eudragit L100-55 ethanol solution;

[0049] S8 enteric activation treatment: spray 0.5% pectinase and 0.1% xylanase dry powder on the outer layer of S7 coating to obtain a selenium-rich microecological preparation.

[0050] The application of selenium-rich proecological preparations in antibiotic-free breeding of meat geese, according to the different growth stages of meat geese in antibiotic-free breeding, targeted intervention diet formula: during the brooding period of meat geese, the selenium-rich proecological preparations are dry-mixed with the daily diet at a ratio of 200g / ton of feed and fed conventionally; during the growth period of meat geese, the selenium-rich proecological preparations are compounded with 0.1% lactic acid solution, prepared with water into a 0.1% solution, and the solution is fed to the meat geese in the form of drinking water; during the fattening period of meat geese, the premix containing selenium-rich proecological preparations is mixed with the daily diet, and the meat geese are fed with intensive feeding.

[0051] The premix is ​​a mixture of selenium-rich microecological preparation, selenium yeast powder and maltodextrin-stone powder carrier.

[0052] Example 2

[0053] A selenium-rich microecological preparation is prepared by the following steps:

[0054] S1 strain activation: Take the freeze-dried powder of Bacillus subtilis, dissolve it in LB medium at a ratio of 1g:10L, and culture it at 40℃ and 150rpm for 15h; take the freeze-dried powder of Enterococcus faecalis, dissolve it in MRS medium at a ratio of 1g:10L, and culture it at 40℃ for 18h in anaerobically static manner; take the freeze-dried powder of Candida utilis, dissolve it in YPD medium at a ratio of 1g:10L, and culture it at 28℃ and 100rpm for 20h in shaking; after the culture is completed, use a continuous centrifuge to collect the bacterial sludge, wash it with PBS buffer after collection, and concentrate it to 1×10^ 12 CFU / mL bacterial suspension;

[0055] Preparation of S2 selenomethionine premix: Dissolve selenomethionine in 55℃ sterile water to prepare 60mg / mL selenomethionine mother solution, and sterilize with filter membrane;

[0056] S3 bacteria-selenium co-culture: the Bacillus subtilis suspension, Enterococcus faecalis suspension and Candida utilis suspension obtained in S1 were mixed in a volume ratio of 2:1:0.5 to obtain a mixed bacterial suspension, 8% selenomethionine mother solution, 1% maltodextrin and 2% xylooligosaccharides were added to the mixed bacterial suspension, and the mixture was cultured at 30°C, pH 6.5 and microaerobic conditions for 5 hours;

[0057] S4 selenoprotein complex formation: add 0.5% chitosan solution by volume to the system after S3 culture, stir, and obtain selenoprotein complex;

[0058] Preparation of S5 coating material: 10% skim milk powder and 8% trehalose were dissolved in deionized water to prepare the water phase; 5% gum arabic and 2% glyceryl monostearate were dissolved in vegetable oil to prepare the oil phase;

[0059] S6 emulsion coating: The selenium-bacteria composite system was mixed with the water phase at a volume ratio of 1:2, and then mixed with the oil phase at a volume ratio of 1:3. After mixing, high-pressure homogenization was performed at 30 MPa; after homogenization, the mixture was spray-dried, and the inlet air temperature of the spray-drying was 85°C, the outlet air temperature was 50°C, the atomization pressure was 0.4-MPa, and the flow rate was 5 L / h to obtain microcapsule particles;

[0060] S7 acid-resistant layer coating: fluidized bed coating using 4% Eudragit L100-55 ethanol solution;

[0061] S8 enteric activation treatment: spray 0.8% pectinase and 0.2% xylanase dry powder on the outer layer of S7 coating to obtain a selenium-rich microecological preparation.

[0062] The application of selenium-rich proecological preparations in antibiotic-free breeding of meat geese, according to the different growth stages of meat geese in antibiotic-free breeding, targeted intervention diet formula: during the brooding period of meat geese, the selenium-rich proecological preparations are dry-mixed with the daily diet at a ratio of 250g / ton of feed, and fed conventionally; during the growth period of meat geese, the selenium-rich proecological preparations are compounded with 0.1% lactic acid solution, prepared with water into a 0.15% solution, and the solution is fed to the meat geese in the form of drinking water; during the fattening period of meat geese, the premix containing selenium-rich proecological preparations is mixed with the daily diet, and the meat geese are fed with intensive feeding.

[0063] The premix is ​​a mixture of selenium-rich microecological preparation, selenium yeast powder and maltodextrin-stone powder carrier.

[0064] Example 3

[0065] A selenium-rich microecological preparation is prepared by the following steps:

[0066] S1 strain activation: Take the freeze-dried powder of Bacillus subtilis, dissolve it in LB medium at a ratio of 1g:10L, and culture it at 30℃ and 120rpm for 18h; take the freeze-dried powder of Enterococcus faecalis, dissolve it in MRS medium at a ratio of 1g:10L, and culture it at 37℃ for 20h in anaerobically static manner; take the freeze-dried powder of Candida utilis, dissolve it in YPD medium at a ratio of 1g:10L, and culture it at 20℃ and 120rpm for 28h in shaking manner; after the culture is completed, use a continuous centrifuge to collect the bacterial sludge, wash it with PBS buffer after collection, and concentrate it to 2×10^ 12 CFU / mL bacterial suspension;

[0067] Preparation of S2 selenomethionine premix: Dissolve selenomethionine in 50℃ sterile water to prepare 50mg / mL selenomethionine mother solution, and sterilize with filter membrane;

[0068] S3 bacteria-selenium co-culture: the Bacillus subtilis suspension, Enterococcus faecalis suspension and Candida utilis suspension obtained in S1 were mixed in a volume ratio of 3:2:1.5 to obtain a mixed bacterial suspension, 10% of the volume of selenomethionine mother solution, 3% of maltodextrin and 0.5% of oligoxylose were added to the mixed bacterial suspension, and the mixture was cultured at 40°C, pH 6.5 and microaerobic conditions for 6 hours;

[0069] S4 selenoprotein complex formation: add 0.8% chitosan solution by volume to the system after S3 culture, stir, and obtain selenoprotein complex;

[0070] Preparation of S5 coating material: 18% skim milk powder and 6% trehalose were dissolved in deionized water to prepare the water phase; 4% gum arabic and 3% glyceryl monostearate were dissolved in vegetable oil to prepare the oil phase;

[0071] S6 emulsion coating: the selenium-bacteria composite system was mixed with the water phase at a volume ratio of 1:4, and then mixed with the oil phase at a volume ratio of 1:5. After mixing, high pressure homogenization was performed at 60 MPa; after homogenization, spray drying was performed, and the inlet air temperature of the spray drying was 70°C, the outlet air temperature was 50°C, the atomization pressure was 0.5 MPa, and the flow rate was 6 L / h to obtain microcapsule particles;

[0072] S7 acid-resistant layer coating: fluidized bed coating using 4% Eudragit L100-55 ethanol solution;

[0073] S8 enteric activation treatment: spray 0.2% pectinase and 0.4% xylanase dry powder on the outer layer of S7 coating to obtain a selenium-rich microecological preparation.

[0074] The application of selenium-rich proecological preparations in antibiotic-free breeding of meat geese, according to the different growth stages of meat geese in antibiotic-free breeding, targeted intervention diet formula: during the brooding period of meat geese, the selenium-rich proecological preparations are dry-mixed with the daily diet at a ratio of 280g / ton of feed, and fed conventionally; during the growth period of meat geese, the selenium-rich proecological preparations are compounded with 0.1% lactic acid solution, prepared with water into a 0.12% solution, and the solution is fed to the meat geese in the form of drinking water; during the fattening period of meat geese, the premix containing selenium-rich proecological preparations is mixed with the daily diet, and the meat geese are fed with intensive feeding.

[0075] The premix is ​​a mixture of selenium-rich microecological preparation, selenium yeast powder and maltodextrin-stone powder carrier.

[0076] Example 4

[0077] A selenium-rich microecological preparation is prepared by the following steps:

[0078] S1 strain activation: Take the freeze-dried powder of Bacillus subtilis, dissolve it in LB medium at a ratio of 1g:10L, and shake culture at 20℃ and 200rpm for 10h; take the freeze-dried powder of Enterococcus faecalis, dissolve it in MRS medium at a ratio of 1g:10L, and culture it at 30℃ for 15h in anaerobically static manner; take the freeze-dried powder of Candida utilis, dissolve it in YPD medium at a ratio of 1g:10L, and shake culture it at 30℃ and 80rpm for 26h; after the culture is completed, use a continuous centrifuge to collect the bacterial sludge, wash it with PBS buffer after collection, and concentrate it to 2×10^ 12 CFU / mL bacterial suspension;

[0079] Preparation of S2 selenomethionine premix: Dissolve selenomethionine in 60℃ sterile water to prepare 45mg / mL selenomethionine mother solution, and sterilize with filter membrane;

[0080] S3 bacteria-selenium co-culture: the Bacillus subtilis suspension, Enterococcus faecalis suspension and Candida utilis suspension obtained in S1 were mixed in a volume ratio of 4:2:1 to obtain a mixed bacterial suspension, 8% selenomethionine mother solution, 1% maltodextrin and 0.8% xylo-oligosaccharide were added to the mixed bacterial suspension, and the mixture was cultured at a temperature of 45°C, pH 6 and microaerobic conditions for 4 hours;

[0081] S4 selenoprotein complex formation: add 0.6% chitosan solution by volume to the system after S3 culture, stir, and obtain selenoprotein complex;

[0082] Preparation of S5 coating material: 15% skim milk powder and 4% trehalose were dissolved in deionized water to prepare the water phase; 2% gum arabic and 1% glyceryl monostearate were dissolved in vegetable oil to prepare the oil phase;

[0083] S6 emulsion coating: The selenium-bacteria composite system was mixed with the water phase at a volume ratio of 1:2.5, and then mixed with the oil phase at a volume ratio of 1:4. After mixing, high-pressure homogenization was performed at 40 MPa; after homogenization, spray drying was performed, and the inlet air temperature of the spray drying was 75°C, the outlet air temperature was 40°C, the atomization pressure was 1 MPa, and the flow rate was 8 L / h to obtain microcapsule particles;

[0084] S7 acid-resistant layer coating: fluidized bed coating using 6% Eudragit L100-55 ethanol solution;

[0085] S8 enteric activation treatment: spray 0.4% pectinase and 0.5% xylanase dry powder on the outer coating layer of S7 to obtain a selenium-rich microecological preparation.

[0086] The application of selenium-rich proecological preparations in antibiotic-free breeding of meat geese, according to the different growth stages of meat geese in antibiotic-free breeding, targeted intervention diet formula: during the brooding period of meat geese, the selenium-rich proecological preparations are dry-mixed with the daily diet at a ratio of 300g / ton of feed and fed conventionally; during the growth period of meat geese, the selenium-rich proecological preparations are compounded with 0.1% lactic acid solution, prepared with water into a 0.14% solution, and the solution is fed to the meat geese in the form of drinking water; during the fattening period of meat geese, the premix containing selenium-rich proecological preparations is mixed with the daily diet, and the meat geese are fed with intensive feeding.

[0087] The premix is ​​a mixture of selenium-rich microecological preparation, selenium yeast powder and maltodextrin-stone powder carrier.

[0088] Comparative Example 1

[0089] It is basically the same as Example 1, except that Bacillus subtilis, Enterococcus faecalis and Candida utilis are not used in the selenium-enriched microecological preparation.

[0090] Comparative Example 2

[0091] It is basically the same as Example 1, except that, in the selenium-enriched microecological preparation, Enterococcus faecalis and Candida utilis are not used, but only Bacillus subtilis is used.

[0092] Comparative Example 3

[0093] It is basically the same as Example 1, except that in the selenium-enriched microecological preparation, Bacillus subtilis and Candida utilis are not used, but only Enterococcus faecalis is used.

[0094] Comparative Example 4

[0095] It is basically the same as Example 1, except that, in the selenium-enriched microecological preparation, Bacillus subtilis and Enterococcus faecalis are not used, but only Candida utilis is used.

[0096] Comparative Example 5

[0097] It is basically the same as Example 1, except that no inducer is added to S3 during the preparation of the selenium-rich microecological preparation.

[0098] Comparative Example 6

[0099] It is basically the same as Example 1, except that no activator is added to S3 during the preparation of the selenium-rich microecological preparation.

[0100] Comparative Example 7

[0101] Normal antibiotic breeding methods are adopted, in which flavonoids is selected as the antibiotic, and the amount of flavonoids added to the daily diet is 5-10 mg / kg feed.

[0102] 1. Meat goose breeding experiment

[0103] 1.1 Detection of selenium content in goose

[0104] 70 healthy, 4-week-old grey geese from Hepu, Guangxi Zhuang Autonomous Region were selected and divided into 10 groups, with 30 geese in each group. The geese were fed with the goose feeds of Examples 1-4 and Comparative Examples 1-7, respectively, and raised until they were ready for market.

[0105] After the geese were fasted for 12 hours, they were weighed and slaughtered. The selenium content in the liver was determined by the AFS method. The records are shown in Table 1.

[0106] Table 1 Selenium content in goose liver

[0107]

[0108]

[0109] From Table 1 we can see that:

[0110] (1) In the present application, in Examples 1-4 using selenium-rich microecological preparations, the selenium content (μg / g) of goose livers reached 7.7, 7.2, 7.4, and 7.5, respectively, indicating that the use of the selenium-rich microecological preparations of the present application and their application in goose farming can result in high selenium content in goose livers, rich nutritional value, and good economic benefits.

[0111] Moreover, in Comparative Examples 1-4 in which the selenium-rich proecological preparation of the present application was not used or was not fully used, the selenium content (μg / g) in the liver of meat geese was 3.2, 4.7, 4.5, and 4.0, respectively, which were all lower than that in Examples 1-4 of the present application, indicating that the selenium-rich proecological preparation of the present application uses Bacillus subtilis, Enterococcus faecalis, and Candida utilis, which can work together to synergistically enhance the selenium content of meat geese.

[0112] This is because: the alkaline protease secreted by Bacillus subtilis and the proton pump of Enterococcus faecalis jointly buffer the gastric acid environment and improve the internal environment of the stomach, while the β-glucan cell wall of Candida utilis forms a nano-scale protective network through physical embedding. The three work together to reduce the degradation rate of selenomethionine in the stomach. After entering the intestine, the metabolites of the flora and the responsive release of the formulation coating material form a linkage. The lipase produced by Bacillus subtilis gradually decomposes the oil phase coating, triggering the targeted dissolution of the enteric material in the ileum. At this time, the mannoprotein of the yeast acts as a bioadhesive, guiding the selenium complex to bind to the intestinal epithelial M cells in a directional manner, greatly improving the transmembrane transport efficiency of selenomethionine.

[0113] At the molecular activation level, Enterococcus faecalis hydrolyzes selenomethionine into selenomethionyl-oligopeptides through specific peptidases, improving its ability to bind to intestinal transporters, while S-adenosylmethionine synthesized by Candida utilis activates the methylation cycle of intestinal cells, prompting selenomethionine to be more efficiently integrated into the selenoprotein synthesis pathway. At the same time, butyrate produced by Bacillus subtilis metabolism accelerates the endocytosis of selenomethionine by regulating ion channels, while glutathione secreted by yeast increases the expression of selenium-specific transporters, forming a dual-channel absorption enhancement effect.

[0114] In terms of intestinal microenvironment regulation, the surfactant secreted by Bacillus subtilis destroys the biofilm of pathogenic bacteria, and the bacteriocins produced by Enterococcus faecalis inhibit competitive microorganisms such as Salmonella, which together increase the abundance of selenium metabolism functional bacteria in the intestinal flora and significantly reduce the non-target consumption of selenomethionine. Candida utilis induces goblet cells to secrete mucin through exosomes, thickens the intestinal mucus layer, and prolongs the retention time of selenium complexes in the absorption site. In addition, the xylooligosaccharides produced by Bacillus subtilis decomposing feed fiber provide a carbon source for Enterococcus faecalis, promoting its synthesis of selenium-binding protein precursors; yeast maintains a low oxygen environment in the intestine, activates the activity of selenocysteine ​​lyase of Enterococcus faecalis, and forms a cascade amplification effect of selenium metabolism.

[0115] At the host system level, the three bacteria work together to achieve targeted enrichment of selenium through the immune-metabolic axis. The Bacillus subtilis activation pathway and yeast signaling synergistically enhance intestinal innate immunity, reduce inflammatory factors, and reduce the ineffective loss of selenium in the anti-inflammatory process. The peptidoglycan of the cell wall of Enterococcus faecalis promotes the gene expression of selenium transporters. The liver receptor pathway regulated by Bacillus subtilis promotes the specific enrichment of selenoprotein P in hepatocytes, achieving efficient distribution of selenium nutrition in key organs.

[0116] Therefore, the combined use of Bacillus subtilis, Enterococcus faecalis and Candida utilis in the present application significantly improves the absorption efficiency of selenomethionine by meat geese through multi-dimensional synergistic effects.

[0117] (3) In comparative example 5 in which the inducer of the present application was not used, the selenium content (μg / g) in the liver of meat geese was 6.2, which was lower than that in Examples 1-4 of the present application. This indicates that the addition of inducers maltodextrin and oligoxylose during the preparation process of the present application can improve the effect of the selenium-enriched microecological preparation and increase the selenium content in meat geese.

[0118] This is because: maltodextrin is a short-chain glucose polymer connected by α-1,4 glycosidic bonds. Its hydrolysis product quickly enters the bacterial glycolysis pathway through the phosphotransferase system. While providing basic energy, it can activate the transcriptional regulatory factors of Bacillus subtilis, induce the expression of amylase gene clusters, and increase the activity of extracellular amylase. This enzymatic reaction not only accelerates its own decomposition, but also can generate oligosaccharide signal molecules such as maltotriose, bind to the membrane receptors of Enterococcus faecalis, and trigger the transport system to preferentially uptake selenomethionine.

[0119] As the hydrolysis product of xylan, the β-1,4-linked xylose units of xylooligosaccharides are recognized as prebiotics by the transcription activator of Candida utilis, activating the expression of xylose reductase and xylitol dehydrogenase genes, coupling the xylose metabolic pathway with the pentose phosphate pathway, and providing key reducing power for the methylation of selenomethionine. On the other hand, the 4-5 degree of polymerization fragments of xylooligosaccharides act as quorum sensing inhibitors, competitively binding with the receptor kinase of Bacillus subtilis, delaying the transmission of biofilm formation signals, prolonging the time that the bacteria maintain the logarithmic growth phase, and significantly improving the selenium integration efficiency.

[0120] (4) In Comparative Example 6 in which the activator of the present application was not used, the selenium content (μg / g) of the liver of meat geese was 6.2, which was lower than that of Examples 1-4 of the present application. This indicates that the addition of activators pectinase and xylanase during the preparation process of the present application can improve the effect of the selenium-enriched microecological preparation and increase the selenium content of meat geese.

[0121] This is because: the cell walls of plant materials in the diet of goose will form a physical barrier to wrap the selenium complex, which is not conducive to the release of organic selenium. Pectinase degrades pectin in plant materials into galacturonic acid oligosaccharides by hydrolyzing α-1,4-galacturonic acid bonds, while xylanase cuts β-1,4-xylosidic bonds to generate xylobiose to xylopentose, increasing the porosity of feed particles, releasing the bound selenomethionine-bacteria complex, and improving the absorption of organic selenium by goose.

[0122] 1.2 Determination of Antibiotic-free Breeding Indexes for Meat Geese

[0123] After the geese were fasted for 12 hours, their daily weight gain, feed-to-weight ratio, diarrhea rate, and mortality rate were calculated. After they were slaughtered, the serum IgB and the proportion of intestinal lactic acid bacteria were determined by ELISA. The records are shown in Table 2.

[0124] Table 2 Comparison of antibiotic-free breeding indicators for meat geese

[0125]

[0126] As can be seen from Table 2, when the selenium-rich microecological preparation of the present application is applied to the antibiotic-free breeding of meat geese, the various indicators are not much different from those of the meat geese raised with conventional antibiotics, and some of the indicators are higher than those of Comparative Example 7, indicating that the selenium-rich microecological preparation of the present application can well replace antibiotics and be applied to the breeding of meat geese.

[0127] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A selenium-rich microecological preparation, characterized in that: The method comprises the following steps: S1. Activation of bacterial strains: freeze-dried powder of Bacillus subtilis, freeze-dried powder of Enterococcus faecalis, and freeze-dried powder of Candida utilis were taken, cultured and activated, and prepared into bacterial suspensions respectively; Preparation of S2 selenomethionine premix: dissolve selenomethionine in 40-60℃ sterile water to prepare 40-60mg / mL selenomethionine mother solution, and sterilize with filter membrane; S3 bacteria-selenium co-culture: the Bacillus subtilis suspension, Enterococcus faecalis suspension and Candida utilis suspension obtained in S1 are mixed according to the volume ratio to obtain a mixed bacterial suspension, 8-12% selenomethionine mother solution is added to the mixed bacterial suspension, and then an inducer is added, and the mixture is statically cultured at a temperature of 30-50°C, pH 6-6.5 and microaerobic conditions for 4-8 hours; S4 selenoprotein complex formation: adding 0.2-0.8% chitosan solution by volume to the system after S3 culture, stirring, and obtaining selenoprotein complex; S5 coating material preparation: preparation of water phase and oil phase; S6 emulsion coating: the selenium-bacteria composite system is mixed with the water phase at a volume ratio of 1:2-4, and then mixed with the oil phase at a volume ratio of 1:3-5. After mixing, high pressure homogenization is performed at 30-60 MPa; after homogenization, spray drying is performed, and the inlet air temperature of the spray drying is 70-85°C, the outlet air temperature is 40-50°C, the atomization pressure is 0.4-1 MPa, and the flow rate is 5-10 L / h to obtain microcapsule particles; S7 acid-resistant layer coating: fluidized bed coating using coating materials; S8 enteric activation treatment: spray the activator on the outer coating layer of S7 to obtain a selenium-rich microecological preparation.

2. The selenium-rich microecological preparation according to claim 1, characterized in that: In S1, the freeze-dried powder of Bacillus subtilis was dissolved in LB medium at a ratio of 1 g: 10 L, and cultured at 20-40°C and 100-200 rpm for 10-18 hours; the freeze-dried powder of Enterococcus faecalis was dissolved in MRS medium at a ratio of 1 g: 10 L, and cultured at 30-40°C for 12-20 hours in an anaerobic static manner; the freeze-dried powder of Candida utilis was dissolved in YDP medium at a ratio of 1 g: 10 L, and cultured at 20-30°C and 80-150 rpm for 20-28 hours; after the culture was completed, the bacterial sludge was collected by a continuous centrifuge, washed with PBS buffer, and concentrated to 1-2×10^ 12 CFU / mL bacterial suspension.

3. The selenium-rich microecological preparation according to claim 1, characterized in that: In S3, the Bacillus subtilis suspension: the Enterococcus faecalis suspension: the Candida utilis suspension are mixed in a volume ratio of 2-4: 1-3: 0.5-1.

5.

4. The selenium-rich microecological preparation according to claim 1, characterized in that: In S3, the synergist is 1-3% maltodextrin and 0.5-2% xylooligosaccharide in the volume of the mixed bacterial suspension.

5. The selenium-rich microecological preparation according to claim 4, characterized in that: In the S5, the aqueous phase is prepared by dissolving 10-18% skimmed milk powder and 2-8% trehalose in deionized water; the oil phase is prepared by dissolving 1-5% gum arabic and 1-3% glyceryl monostearate in vegetable oil.

6. The selenium-rich microecological preparation according to claim 1, characterized in that: In S7, the coating material is 4-6% Eudragit L100-55.

7. The selenium-rich microecological preparation according to claim 1, characterized in that: In S8, the activator is 0.2-0.8% pectinase and 0.1-0.5% xylanase dry powder.

8. The use of the selenium-rich microecological preparation according to claim 1 in antibiotic-free breeding of meat geese, characterized in that: According to the different growth stages of meat geese in antibiotic-free breeding, targeted intervention dietary formula is adopted: during the brooding period, selenium-rich proecological preparations are dry-mixed with daily feed at a ratio of 200-300g / ton of feed and fed conventionally; during the growth period, the selenium-rich proecological preparations are acidified and prepared into a solution, and the solution is fed to the meat geese in the form of drinking water; during the fattening period, the premix containing selenium-rich proecological preparations is mixed with the daily diet, and the meat geese are fed with intensive feeding.

9. The use of the selenium-rich microecological preparation according to claim 8 in antibiotic-free breeding of meat geese, characterized in that: The acidification method of the selenium-rich microecological preparation is: compound the selenium-rich microecological preparation with 0.1% lactic acid solution, and prepare it with water into a 0.1-0.15% solution.

10. The use of the selenium-rich microecological preparation according to claim 8 in antibiotic-free breeding of meat geese, characterized in that: The premix is ​​a mixture of selenium-rich microecological preparation, selenium yeast powder and maltodextrin-stone powder carrier.

Images