A kind of high-selenium-enriched eggs and feeding method of laying hens

Abstract

The present invention relates to the technical field of poultry breeding, and in particular to a method for feeding high-selenium-enriched eggs and laying hens, comprising the following steps: S1) pretreatment of materials, S2) preparation of culture medium, S3) screening of fermentation strains, and S4) feeding of laying hens. The feeding method for laying hens provided in the present invention effectively improves fermentation efficiency, shortens fermentation cycle, inhibits the growth of pathogenic bacteria in the fermentation environment, reduces the content of harmful microorganisms in the extract obtained by fermentation, and is beneficial to maintaining the health of animal bodies, improving the digestion and absorption utilization rate of animals, and is beneficial to the rapid and healthy growth of animals. It not only improves the immunity and lifespan of laying hens, increases egg production rate, but also is beneficial to the production of high-selenium-enriched eggs.

Description

Technical Field

[0001] The invention relates to the technical field of poultry breeding, and in particular to a feeding method for high-selenium-enriched eggs and laying hens. Background Art

[0002] Selenium is an essential trace element for the human body and has important physiological functions. It can prevent and inhibit tumors, resist aging, maintain the normal structure and function of the cardiovascular system, prevent arteriosclerosis and coronary heart disease, and has antioxidant, anti-tumor and immunity-enhancing effects. Therefore, selenium supplementation is very important for maintaining the health of selenium-deficient people. Eggs are rich in high-quality protein, vitamins and minerals, and are one of the best sources of nutrition for humans. Due to their rich nutrition, good quality, low price and convenient cooking, eggs are also the most common animal food on people's tables. Therefore, the development of selenium-enriched eggs is the simplest and most effective way to solve the problem of selenium deficiency in my country.

[0003] For example, the invention patent with announcement number CN104430145A discloses a method for producing selenium-enriched eggs, which comprises crushing selenium-enriched ryegrass, and then evenly mixing the ryegrass crushed grains into the laying hen feed according to a certain weight percentage to make the selenium concentration reach 0.4mg / kg-0.6mg / kg to obtain selenium-enriched ryegrass feed, and feeding the laying hen with the selenium-enriched ryegrass feed according to conventional feeding methods, and producing selenium-enriched eggs after 1-2 weeks; the production method comprises mixing the selenium-enriched ryegrass with the feed and feeding it to the laying hen. Although the feed is rich in selenium, the laying hen is not sensitive to the selenium-enriched ryegrass by directly feeding the selenium-enriched ryegrass. The digestion and absorption rate is low, so that a large amount of selenium will be excreted with the feces of laying hens, resulting in a low selenium content in the eggs laid by laying hens; for example, the invention patent with announcement number CN107772135A discloses a method for producing selenium-enriched chicken feed and selenium-enriched eggs, in which selenium-enriched chicken feed is obtained by fermenting the ingredients with selenium-enriched yeast. Although it is beneficial for laying hens to digest and utilize the selenium-enriched chicken feed, the fermentation efficiency of the selenium-enriched yeast itself and the growth of harmful microorganisms during the fermentation process will lead to low fermentation efficiency, resulting in low selenium concentration in selenium-enriched chicken feed, resulting in low selenium content in eggs, thereby affecting the nutritional value of eggs. Summary of the invention

[0004] The purpose of the present invention is to provide a method for feeding high-selenium-enriched eggs and laying hens in order to solve the problems existing in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for feeding high-selenium-enriched laying hens, specifically comprising the following steps:

[0007] S1) Pre-processing of materials

[0008] Selenium-enriched mulberry leaves, selenium-enriched corn, selenium-enriched soybeans, selenium-enriched salvia leaf powder, selenium-enriched peanut cakes, selenium-enriched wheat husks, and selenium-enriched rice husks are mixed and then water is added for low-temperature hot water hydrolysis to obtain a wet material, and then the low-temperature hot water is drained, the container is placed in a microwave environment, and after water is added, high-temperature hot water hydrolysis is performed under the assistance of ultrasound to obtain a pretreated material;

[0009] S2) Preparation of culture medium

[0010] The first culture medium is prepared by using yeast powder, peptone, sodium chloride and water; the inorganic culture medium is prepared by using potassium dihydrogen phosphate, magnesium sulfate and water, and the first culture medium and the inorganic culture medium are mixed to prepare an acclimation culture medium; the screening culture medium is prepared by using pretreated materials, potassium dihydrogen phosphate, yeast powder, peptone, magnesium sulfate, sodium chloride, agar and water;

[0011] S3) Screening of fermentation strains

[0012] Using an inoculation loop, take a loop of Lactobacillus plantarum and Aspergillus oryzae respectively, inoculate them into the acclimation medium for acclimation, apply the acclimated strains into the screening medium, inoculate them into the first medium after purification and culture for 24-30 hours to obtain a mixed strain liquid;

[0013] The pathogenic bacteria are inoculated into the first culture medium to obtain a bacterial suspension after cultivation, and then the first culture medium is injected into the culture dish, agar powder is added, and the bacterial suspension is inoculated after being allowed to stand horizontally to solidify to obtain an indicator bacteria plate, and the Oxford cup is placed vertically on the prepared indicator bacteria plate, and is lightly pressed with tweezers to make it in close contact with the surface of the culture medium, and the mixed bacterial strain liquid is added to the Oxford cup respectively, and after standing at room temperature for 1-3 hours, it is placed in a 36-38° C. biochemical incubator for 12-20 hours to obtain a fermentation strain;

[0014] S4) Feeding of laying hens

[0015] The pretreated material is inoculated with fermentation bacteria, warm water is added to prepare fermentation raw materials, and the fermentation material is fermented at 38-42°C for 4-6 days. The fermented material is subjected to oscillation extraction and centrifugation to obtain an extract, and the extract is concentrated to 0.8-1.2 mg / L, which is added to chicken feed to obtain high-selenium-rich feed. Then, from the beginning of hatching, the high-selenium-rich feed and the extract are used for feeding and drinking by chickens to obtain high-selenium-rich laying hens.

[0016] As a further preferred embodiment of the present invention, the temperature of the low-temperature thermal hydrolysis is 70-80°C, and the hydrolysis time is 30-60min;

[0017] The temperature of the high temperature thermal hydrolysis is 130-170°C, and the hydrolysis time is 20-40min;

[0018] In the microwave environment, the frequency is between 100-300 GHz and the wavelength is between 0.1-100 mm;

[0019] The power of the ultrasonic assistance is 800-1200W.

[0020] As a further preferred embodiment of the present invention, the preparation method of the first culture medium is as follows: add 5-10g yeast powder, 10-20g peptone, and 5-10g sodium chloride, make up to 1000-1500mL with water, adjust the pH to 7 with 5-8mol / L sodium hydroxide solution, and sterilize at 121-123°C for 10-20min.

[0021] As a further preferred embodiment of the present invention, the preparation method of the acclimated culture medium is as follows: 3-5g of potassium dihydrogen phosphate and 3-5g of magnesium sulfate are added with water to make the volume to 1000-1300mL, and sterilized at 121-123°C for 10-20min to obtain an inorganic culture medium, and 25-35mL of the first culture medium and 30-50mL of the inorganic culture medium are mixed, and sterilized at 121-123°C for 10-20min.

[0022] As a further preferred embodiment of the present invention, the preparation method of the screening medium is as follows: 10-20g of pretreated material, 1-3g of potassium dihydrogen phosphate, 1-2g of yeast powder, 2-5g of peptone, 0.3-0.8g of magnesium sulfate, 0.5-0.9g of sodium chloride, and 13-18g of agar are added with water to make up to 1000-1500mL, and sterilized at 121-123°C for 10-20min.

[0023] As a further preferred embodiment of the present invention, the acclimation needs to be performed 3-5 times, and each acclimation is performed in a shaker at 220-260 r / min and 30-35° C. for 6-8 days;

[0024] The purification needs to be performed 3-5 times.

[0025] As a further preferred embodiment of the present invention, the pathogenic bacteria are composed of equal amounts of Escherichia coli and Staphylococcus aureus;

[0026] The concentration of the bacterial suspension is (5-7)×10 7 CFU / mL;

[0027] The amount of agar powder added is equal to the mass of peptone in the first culture medium injected into the culture dish;

[0028] The ratio of the inoculation volume of the bacterial suspension to the volume of the first culture medium in the culture dish is (100-160) μL: (20-30) mL;

[0029] The ratio of the amount of the mixed bacterial liquid added to the amount of the first culture medium in the culture dish is (200-300) μL: (20-30) mL.

[0030] As a further preferred embodiment of the present invention, the inoculation amount of the fermentation bacteria accounts for 1-3‰ of the weight of the pretreated material;

[0031] The fermentation raw material has a moisture content of 40-46 wt %;

[0032] In the high-selenium-rich feed, the extract accounts for 1-5% of the weight of the chicken feed;

[0033] The chicken feed is composed of corn, soybean cake, fish meal, soybean lecithin and complex vitamins according to the mass ratio of (100-130): (13-18): (8-12): (0.3-0.7): (1-4).

[0034] As a further preferred embodiment of the present invention, the feeding method of the high-selenium-enriched laying hens is as follows:

[0035] From hatching to 6 weeks of age, feed high-selenium-rich feed, 20-30g per day, 3-7 times a day, drink the extract during this period, and expose to light for 7-8 hours a day, with a light intensity of 10-14 lux. From 7-15 weeks of age, feed high-selenium-rich feed, 115-135g per day, 3-5 times a day, drink the extract during this period, expose to light for 8-10 hours a day, with a light intensity of 5-9 lux. Finally, from 16-30 weeks of age, feed high-selenium-rich feed, 140-170g per day, 3-5 times a day, drink the extract during this period, expose to light for 15-17 hours a day, with a light intensity of 10-15 lux.

[0036] A high-selenium-enriched egg is produced by a high-selenium-enriched laying hen fed using a feeding method for a high-selenium-enriched laying hen.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] In order to promote the full release of selenium in the material, in the present invention, the selenium-rich material is pretreated. First, the selenium-rich material is treated by low-temperature thermal hydrolysis. On the one hand, the cells in the material are expanded by heat, and the membrane pore size of the cell membrane becomes larger, which is beneficial to the subsequent fermentation process. A large amount of organic matter in the cells is released into the liquid phase. On the other hand, low-temperature thermal hydrolysis is equivalent to preheating the material, improving the adaptability of the cells in the material to temperature changes, and avoiding the loss of organic matter due to a large number of ruptures of the cell membrane in the subsequent high-temperature thermal hydrolysis; secondly, the selenium-rich material is secondary treated by high-temperature thermal hydrolysis under ultrasonic assistance and microwave environment. While further increasing the membrane pore size of the cell membrane, it can destroy the cell structure and promote the breaking of the strong chemical bonds of the organic matter in the cell, so that the macromolecular organic matter is hydrolyzed into small molecular substances, which is beneficial to improve the subsequent fermentation efficiency and shorten the fermentation time.

[0039] In order to further improve the fermentation efficiency, the present invention screens the fermentation strains to obtain fermentation strains with high fermentation activity and antibacterial performance. First, plant lactobacillus and Aspergillus oryzae are domesticated to achieve the effect of enhanced screening, and screening and culturing are carried out in a screening culture medium containing a pretreated material, so that the strain diversity is richer and more uniform, and the abundance of carbohydrate metabolic pathways is improved, thereby improving its growth and fermentation ability in the pretreated material, thereby obtaining a mixed strain with high fermentation performance for the pretreated material, thereby achieving the effect of shortening the fermentation cycle and improving the fermentation ability; in order to inhibit the growth of pathogenic bacteria during the fermentation process, the present invention screens the fermentation strains to obtain a fermentation strain with high fermentation activity and antibacterial performance. The obtained mixed strains were subjected to secondary screening. The mixed strains were inoculated in a culture medium containing a pathogenic bacteria suspension for cultivation, thereby enhancing the competitive ability of the mixed strains with the pathogenic bacteria for nutrients, thereby inhibiting the growth and reproduction of the pathogenic bacteria, thereby obtaining a fermentation strain with high antibacterial properties. During the fermentation process, the fermentation strain can not only efficiently absorb nutrients and reproduce rapidly, thereby further improving the fermentation efficiency, but also inhibit the growth of pathogenic bacteria in the fermentation environment and reduce the content of harmful microorganisms in the extract obtained by fermentation, which is beneficial to maintaining the health of the animal body and improving the digestion and absorption utilization rate of the animal, thereby facilitating the rapid and healthy growth of the animal.

[0040] The feeding method for laying hens provided in the present invention pretreats selenium-rich materials and screens Lactobacillus plantarum and Aspergillus oryzae used for fermentation, thereby effectively improving the fermentation efficiency, shortening the fermentation cycle, and inhibiting the growth of pathogenic bacteria in the fermentation environment, reducing the content of harmful microorganisms in the extract obtained by fermentation, thereby being beneficial to maintaining the health of the animal body, improving the digestion and absorption utilization rate of the animal, and thus being beneficial to the rapid and healthy growth of the animal. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Example 1

[0043] A method for feeding high-selenium-enriched laying hens, specifically comprising the following steps:

[0044] S1) Pre-processing of materials

[0045] Add equal amounts of selenium-enriched mulberry leaves, selenium-enriched corn, selenium-enriched soybeans, selenium-enriched salvia miltiorrhiza leaf powder, selenium-enriched peanut cakes, selenium-enriched wheat husks, and selenium-enriched rice husks into a container in sequence, mix well to obtain a material, and according to a mass volume ratio of material to water of 1g:50mL, add water into the container, heat to 70°C, and perform low-temperature hot water hydrolysis for 30 minutes to obtain a wet material;

[0046] After draining the hot water in the container, water was added to the container and heated to 130°C according to the mass volume ratio of wet material to water of 1g:80mL, and high-temperature thermal hydrolysis was performed for 20 minutes under the assistance of 800W ultrasound. During the high-temperature thermal hydrolysis, the container was placed in a microwave environment with a frequency of 100GHz and a wavelength of 50mm. The product was taken out and the water was drained to obtain the pretreated material for standby use;

[0047] S2) Preparation of culture medium

[0048] 5 g of yeast powder, 10 g of peptone, and 5 g of sodium chloride were added with water to make the volume 1000 mL, the pH was adjusted to 7 with a 5 mol / L sodium hydroxide solution, and sterilized at 121° C. for 10 min to prepare a first culture medium;

[0049] 3 g of potassium dihydrogen phosphate and 3 g of magnesium sulfate were added with water to a volume of 1000 mL, and sterilized at 121° C. for 10 min to obtain an inorganic culture medium; 25 mL of the first culture medium and 30 mL of the inorganic culture medium were mixed, and sterilized at 121° C. for 10 min to prepare an acclimated culture medium;

[0050] 10 g of pretreated material, 1 g of potassium dihydrogen phosphate, 1 g of yeast powder, 2 g of peptone, 0.3 g of magnesium sulfate, 0.5 g of sodium chloride, and 13 g of agar were added with water to make the volume to 1000 mL, and sterilized at 121° C. for 10 min to prepare a screening medium;

[0051] S3) Screening of fermentation strains

[0052] Using an inoculation loop, take a loop of Lactobacillus plantarum and Aspergillus oryzae respectively, inoculate in the acclimation medium for acclimation 3 times, and culture in a shaker at 220 r / min and 30° C. for 6 days each time, spread the acclimated strains in the screening medium, purify 3 times, inoculate in the first medium and culture for 24 hours to obtain a mixed strain liquid;

[0053] Escherichia coli and Staphylococcus aureus were inoculated into the first culture medium, cultured overnight at 35°C for 12 h, and diluted to a concentration of 5×10 7 CFU / mL of bacterial suspension, then inject 20mL of the first culture medium into the culture dish, add agar powder with the same content as peptone, let it stand horizontally to solidify, inoculate 100μL of bacterial suspension of Escherichia coli and Staphylococcus aureus respectively, to obtain indicator bacteria plates, put the Oxford cup vertically on the two prepared indicator bacteria plates, press it lightly with tweezers to make it in close contact with the surface of the culture medium, add 200μL of mixed bacterial liquid to the Oxford cup respectively, let it stand at room temperature for 1h, and then put it in a 36℃ biochemical incubator for 12h to obtain fermentation strains;

[0054] S4) Feeding of laying hens

[0055] The pretreated material is inoculated with a fermentation strain accounting for 1‰ of the weight of the pretreated material, warm water is added to prepare a fermentation raw material with a moisture content of 40wt%, and the fermentation material is fermented at 38°C for 4 days, and the obtained fermentation material is shaken and extracted at 120 / min for 3 days, and centrifuged at 3000r / min for 10 minutes to obtain an extract, and the extract is concentrated to 0.8mg / L, and added to chicken feed, and the extract is controlled to account for 1% of the weight of the chicken feed to obtain a high-selenium-rich feed, wherein the chicken feed is composed of corn, soybean cake, fish meal, soybean lecithin, and complex vitamins according to a mass ratio of 100:13:8:0.3:1;

[0056] From hatching to 6 weeks of age, they are fed with high-selenium-rich feed, 20g per bird per day, 3 times a day, during which time they drink the extract, and are exposed to light for 7 hours a day, with a light intensity of 10 lux. From 7-15 weeks of age, they are fed with high-selenium-rich feed, 115g per bird per day, 3 times a day, during which time they drink the extract, and are exposed to light for 8 hours a day, with a light intensity of 5 lux. Finally, from 16-30 weeks of age, they are fed with high-selenium-rich feed, 140g per bird per day, 3 times a day, during which time they drink the extract, and are exposed to light for 15 hours a day, with a light intensity of 10 lux, thus obtaining high-selenium laying hens.

[0057] Example 2

[0058] A method for feeding high-selenium-enriched laying hens, specifically comprising the following steps:

[0059] S1) Pre-processing of materials

[0060] Add equal amounts of selenium-enriched mulberry leaves, selenium-enriched corn, selenium-enriched soybeans, selenium-enriched salvia miltiorrhiza leaf powder, selenium-enriched peanut cakes, selenium-enriched wheat husks, and selenium-enriched rice husks into a container in sequence, mix well to obtain a material, and according to the mass volume ratio of the material to water of 1g:80mL, add water into the container, heat to 75°C, and perform low-temperature hot water hydrolysis for 50min to obtain a wet material;

[0061] After draining the hot water in the container, water was added to the container and heated to 150°C according to the mass volume ratio of wet material to water of 1g:120mL, and high-temperature thermal hydrolysis was performed for 30 minutes under the assistance of 1000W ultrasound. During the high-temperature thermal hydrolysis, the container was placed in a microwave environment with a frequency of 200GHz and a wavelength of 80mm. The product was taken out and the water was drained to obtain the pretreated material for standby use;

[0062] S2) Preparation of culture medium

[0063] 7 g of yeast powder, 15 g of peptone, and 7 g of sodium chloride were added with water to make the volume 1200 mL, the pH was adjusted to 7 with a 6 mol / L sodium hydroxide solution, and sterilized at 122° C. for 15 min to prepare a first culture medium;

[0064] 4 g of potassium dihydrogen phosphate and 4 g of magnesium sulfate were added with water to a volume of 1200 mL, and sterilized at 122° C. for 15 min to obtain an inorganic culture medium; 30 mL of the first culture medium and 40 mL of the inorganic culture medium were mixed, and sterilized at 122° C. for 15 min to prepare an acclimated culture medium;

[0065] 15 g of pretreated material, 2 g of potassium dihydrogen phosphate, 1.5 g of yeast powder, 4 g of peptone, 0.5 g of magnesium sulfate, 0.8 g of sodium chloride, and 15 g of agar were added with water to make the volume to 1200 mL, and sterilized at 122° C. for 15 min to prepare a screening medium;

[0066] S3) Screening of fermentation strains

[0067] Using an inoculation loop, take a loop of Lactobacillus plantarum and Aspergillus oryzae respectively, inoculate in the acclimation medium for 4 times, and culture in a shaker at 240 r / min and 32° C. for 7 days each time, spread the acclimated strains in the screening medium, purify 4 times, inoculate in the first medium and culture for 28 hours to obtain a mixed strain liquid;

[0068] Escherichia coli and Staphylococcus aureus were inoculated into the first culture medium, cultured overnight at 36°C for 15 h, and diluted to a concentration of 6×10 7CFU / mL of bacterial suspension, then inject 25mL of the first culture medium into the culture dish, add agar powder with the same content as peptone, let it stand horizontally to solidify, inoculate 140μL of bacterial suspension of Escherichia coli and Staphylococcus aureus respectively, to obtain indicator bacteria plates, vertically place the Oxford cup on the two prepared indicator bacteria plates, press it lightly with tweezers to make it in close contact with the surface of the culture medium, add 280μL of mixed bacterial liquid to the Oxford cup respectively, let it stand at room temperature for 2h, and then culture it in a 37℃ biochemical incubator for 16h to obtain fermentation strains;

[0069] S4) Feeding of laying hens

[0070] The pretreated material is inoculated with a fermentation strain accounting for 2‰ of the weight of the pretreated material, warm water is added to prepare a fermentation raw material with a moisture content of 45wt%, and the fermentation material is fermented at 40°C for 5 days. The obtained fermentation material is shaken and extracted at 160 / min for 4 days, and centrifuged at 4000r / min for 15 minutes to obtain an extract, and the extract is concentrated to 1mg / L, and added to chicken feed, and the extract is controlled to account for 3% of the weight of the chicken feed to obtain a high-selenium-rich feed, wherein the chicken feed is composed of corn, soybean cake, fish meal, soybean lecithin, and complex vitamins in a mass ratio of 115:15:10:0.6:3;

[0071] From hatching to 6 weeks of age, they are fed with high-selenium-rich feed, 25g per bird per day, 5 times a day, during which they drink the extract, and are exposed to light for 7 hours a day, with a light intensity of 12 lux. From 7-15 weeks of age, they are fed with high-selenium-rich feed, 120g per bird per day, 4 times a day, during which they drink the extract, and are exposed to light for 9 hours a day, with a light intensity of 8 lux. Finally, from 16-30 weeks of age, they are fed with high-selenium-rich feed, 160g per bird per day, 4 times a day, during which they drink the extract, and are exposed to light for 16 hours a day, with a light intensity of 12 lux, thus obtaining high-selenium laying hens.

[0072] Example 3

[0073] A method for feeding high-selenium-enriched laying hens, specifically comprising the following steps:

[0074] S1) Pre-processing of materials

[0075] Add equal amounts of selenium-enriched mulberry leaves, selenium-enriched corn, selenium-enriched soybeans, selenium-enriched salvia miltiorrhiza leaf powder, selenium-enriched peanut cakes, selenium-enriched wheat husks, and selenium-enriched rice husks into a container in sequence, mix well to obtain a material, and according to a mass volume ratio of material to water of 1 g:100 mL, add water into the container, heat to 80°C, and perform low-temperature hot water hydrolysis for 60 min to obtain a wet material;

[0076] After draining the hot water in the container, water was added to the container and heated to 170°C according to the mass volume ratio of wet material to water of 1g:130mL, and high-temperature thermal hydrolysis was performed for 40 minutes under the assistance of 1200W ultrasound. During the high-temperature thermal hydrolysis, the container was placed in a microwave environment with a frequency of 300GHz and a wavelength of 100mm. The product was taken out and the water was drained to obtain the pretreated material for standby use;

[0077] S2) Preparation of culture medium

[0078] 10 g of yeast powder, 20 g of peptone, and 10 g of sodium chloride were added with water to make the volume 1500 mL, and the pH was adjusted to 7 with 8 mol / L sodium hydroxide solution, and sterilized at 123° C. for 20 min to prepare a first culture medium;

[0079] 5 g of potassium dihydrogen phosphate and 5 g of magnesium sulfate were added with water to a volume of 1300 mL, and sterilized at 123° C. for 20 min to obtain an inorganic culture medium; 35 mL of the first culture medium and 50 mL of the inorganic culture medium were mixed, and sterilized at 123° C. for 20 min to prepare an acclimation culture medium;

[0080] 20 g of pretreated material, 3 g of potassium dihydrogen phosphate, 2 g of yeast powder, 5 g of peptone, 0.8 g of magnesium sulfate, 0.9 g of sodium chloride, and 18 g of agar were added with water to make the volume to 1500 mL, and sterilized at 123° C. for 20 min to prepare a screening medium;

[0081] S3) Screening of fermentation strains

[0082] Using an inoculation loop, take a loop of Lactobacillus plantarum and Aspergillus oryzae respectively, inoculate in the acclimation medium for acclimation 5 times, and culture in a shaker at 260 r / min and 35° C. for 8 days each time, spread the acclimated strains in the screening medium, purify 5 times, inoculate in the first medium and culture for 30 hours to obtain a mixed strain liquid;

[0083] Escherichia coli and Staphylococcus aureus were inoculated into the first culture medium, cultured overnight at 38°C for 16 h, and diluted to a concentration of 7×10 7 CFU / mL of bacterial suspension, then inject 30mL of the first culture medium into the culture dish, add agar powder with the same content as peptone, let it stand horizontally to solidify, inoculate 160μL of bacterial suspension of Escherichia coli and Staphylococcus aureus respectively, to obtain indicator bacteria plates, put the Oxford cup vertically on the two prepared indicator bacteria plates, press it lightly with tweezers to make it in close contact with the surface of the culture medium, add 300μL of mixed bacterial liquid to the Oxford cup respectively, let it stand at room temperature for 3h, and then put it in a 38℃ biochemical incubator for 20h to obtain fermentation strains;

[0084] S4) Feeding of laying hens

[0085] The pretreated material is inoculated with a fermentation strain accounting for 3‰ of the weight of the pretreated material, warm water is added to prepare a fermentation raw material with a moisture content of 46wt%, and the fermentation material is fermented at 42°C for 6 days. The obtained fermentation material is shaken and extracted at 180 / min for 4 days, and centrifuged at 5000r / min for 20 minutes to obtain an extract, and the extract is concentrated to 1.2mg / L, and added to chicken feed, and the extract is controlled to account for 5% of the weight of the chicken feed to obtain a high-selenium-rich feed, wherein the chicken feed is composed of corn, soybean cake, fish meal, soybean lecithin, and complex vitamins in a mass ratio of 130:18:8:0.7:4;

[0086] From hatching to 6 weeks of age, they are fed with high-selenium-rich feed, 30g per bird per day, 7 times a day, during which time they drink the extract, and are exposed to light for 8 hours a day, with a light intensity of 14 lux. From 7-15 weeks of age, they are fed with high-selenium-rich feed, 135g per bird per day, 5 times a day, during which time they drink the extract, and are exposed to light for 10 hours a day, with a light intensity of 9 lux. Finally, from 16-30 weeks of age, they are fed with high-selenium-rich feed, 170g per bird per day, 5 times a day, during which time they drink the extract, and are exposed to light for 17 hours a day, with a light intensity of 15 lux, thus obtaining high-selenium laying hens.

[0087] Comparative Example 1: This comparative example is substantially the same as Example 1, except that the material is not subjected to low-temperature thermal hydrolysis.

[0088] Comparative Example 2: This comparative example is basically the same as Example 1, except that during the high-temperature thermal hydrolysis process, ultrasonic assistance was not applied and the container was not placed in a microwave environment.

[0089] Comparative Example 3: This comparative example is basically the same as Example 1, except that during the culture of the mixed bacterial liquid, Lactobacillus plantarum and Aspergillus oryzae were not domesticated.

[0090] Comparative Example 4: This comparative example is basically the same as Example 1, except that equal amounts of Lactobacillus plantarum and Aspergillus oryzae are used to replace the fermentation bacteria.

[0091] Comparative Example 5: This comparative example is basically the same as Example 1, except that a mixed bacterial liquid is used instead of the fermentation bacteria.

[0092] Test Trial:

[0093] The feeding methods provided in Examples 1-3 and Comparative Examples 1-5 were used to obtain high-selenium-enriched laying hens, and selenium-enriched eggs were obtained by the high-selenium-enriched laying hens. The high-selenium-enriched laying hens and selenium-enriched eggs were tested, and the data results obtained were as follows:

[0094] Feed to meat ratio Feed to Egg Ratio Egg production rate% Selenium content in eggs μg / g Average egg weight g Example 1 1.39 2.05 82.6 0.82 67.5 Example 2 1.35 2.01 84.3 0.87 68.7 Example 3 1.38 2.03 83.7 0.84 68.2 Comparative Example 1 1.59 2.33 72.3 0.69 62.5 Comparative Example 2 1.62 2.37 70.2 0.65 60.8 Comparative Example 3 1.67 2.45 65.4 0.56 56.2 Comparative Example 4 1.73 2.49 63.2 0.51 53.1 Comparative Example 5 1.63 2.41 68.1 0.60 58.3

[0095] It can be seen from the above table that the feeding method of the present invention effectively reduces the feed-to-meat ratio and the feed-to-egg ratio, significantly improves the egg production rate, and significantly increases the selenium content in eggs, with a stable content and better nutritional health.

[0096] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for feeding high-selenium laying hens, characterized in that: The specific steps include: S1) Pre-processing of materials Selenium-enriched mulberry leaves, selenium-enriched corn, selenium-enriched soybeans, selenium-enriched salvia leaf powder, selenium-enriched peanut cakes, selenium-enriched wheat husks, and selenium-enriched rice husks are mixed and then water is added for low-temperature hot water hydrolysis to obtain a wet material, and then the low-temperature hot water is drained, the container is placed in a microwave environment, and after water is added, high-temperature hot water hydrolysis is performed under the assistance of ultrasound to obtain a pretreated material; S2) Preparation of culture medium The first culture medium is prepared by using yeast powder, peptone, sodium chloride and water; the inorganic culture medium is prepared by using potassium dihydrogen phosphate, magnesium sulfate and water, and the first culture medium and the inorganic culture medium are mixed to prepare an acclimation culture medium; the screening culture medium is prepared by using pretreated materials, potassium dihydrogen phosphate, yeast powder, peptone, magnesium sulfate, sodium chloride, agar and water; S3) Screening of fermentation strains Using an inoculation loop, take a loop of Lactobacillus plantarum and Aspergillus oryzae respectively, inoculate them into the acclimation medium for acclimation, apply the acclimated strains into the screening medium, inoculate them into the first medium after purification and culture for 24-30 hours to obtain a mixed strain liquid; The pathogenic bacteria are inoculated into the first culture medium to obtain a bacterial suspension after cultivation, and then the first culture medium is injected into the culture dish, agar powder is added, and the bacterial suspension is inoculated after being allowed to stand horizontally to solidify to obtain an indicator bacteria plate, and the Oxford cup is placed vertically on the prepared indicator bacteria plate, and is lightly pressed with tweezers to make it in close contact with the surface of the culture medium, and the mixed bacterial strain liquid is added to the Oxford cup respectively, and after standing at room temperature for 1-3 hours, it is placed in a 36-38° C. biochemical incubator for 12-20 hours to obtain a fermentation strain; S4) Feeding of laying hens The pretreated material is inoculated with fermentation bacteria, warm water is added to prepare fermentation raw materials, and the fermentation material is fermented at 38-42°C for 4-6 days. The fermented material is subjected to oscillation extraction and centrifugation to obtain an extract, and the extract is concentrated to 0.8-1.2 mg / L, which is added to chicken feed to obtain high-selenium-rich feed. Then, from the beginning of hatching, the high-selenium-rich feed and the extract are used for feeding and drinking by chickens to obtain high-selenium-rich laying hens.

2. The feeding method of a high-selenium-enriched laying hen according to claim 1, characterized in that: The temperature of the low-temperature hot water hydrolysis is 70-80°C, and the hydrolysis time is 30-60min; The temperature of the high temperature thermal hydrolysis is 130-170°C, and the hydrolysis time is 20-40min; In the microwave environment, the frequency is between 100-300 GHz and the wavelength is between 0.1-100 mm; The power of the ultrasonic assistance is 800-1200W.

3. The feeding method of a high-selenium-enriched laying hen according to claim 1, characterized in that: The preparation method of the first culture medium is as follows: add 5-10g yeast powder, 10-20g peptone, and 5-10g sodium chloride, and make up the volume to 1000-1500mL with water, adjust the pH to 7 with 5-8mol / L sodium hydroxide solution, and sterilize at 121-123°C for 10-20min.

4. The feeding method of a high-selenium-enriched laying hen according to claim 1, characterized in that: The preparation method of the acclimation medium is as follows: 3-5g potassium dihydrogen phosphate and 3-5g magnesium sulfate are added with water to make the volume to 1000-1300mL, and sterilized at 121-123°C for 10-20min to obtain an inorganic medium, and 25-35mL of the first medium and 30-50mL of the inorganic medium are mixed, and sterilized at 121-123°C for 10-20min.

5. The feeding method of a high-selenium-enriched laying hen according to claim 1, characterized in that: The preparation method of the screening medium is as follows: 10-20g of pretreated material, 1-3g of potassium dihydrogen phosphate, 1-2g of yeast powder, 2-5g of peptone, 0.3-0.8g of magnesium sulfate, 0.5-0.9g of sodium chloride, and 13-18g of agar are added with water to make the volume to 1000-1500mL, and sterilized at 121-123°C for 10-20min.

6. The feeding method of a high-selenium-enriched laying hen according to claim 1, characterized in that: The acclimation needs to be performed 3-5 times, and each acclimation is performed in a shaker at 220-260 r / min and 30-35° C. for 6-8 days; The purification needs to be performed 3-5 times.

7. The feeding method of a high-selenium-enriched laying hen according to claim 1, characterized in that: The pathogenic bacteria consist of equal amounts of Escherichia coli and Staphylococcus aureus; The concentration of the bacterial suspension is (5-7)×10 7 CFU / mL; The amount of agar powder added is equal to the mass of peptone in the first culture medium injected into the culture dish; The ratio of the inoculation volume of the bacterial suspension to the volume of the first culture medium in the culture dish is (100-160) μL: (20-30) mL; The ratio of the amount of the mixed bacterial liquid added to the amount of the first culture medium in the culture dish is (200-300) μL: (20-30) mL.

8. The method for feeding high-selenium-enriched laying hens according to claim 1, characterized in that: The inoculation amount of the fermentation bacteria accounts for 1-3‰ of the weight of the pretreated material; The fermentation raw material has a moisture content of 40-46 wt %; In the high-selenium-rich feed, the extract accounts for 1-5% of the weight of the chicken feed; The chicken feed is composed of corn, soybean cake, fish meal, soybean lecithin and complex vitamins according to the mass ratio of (100-130): (13-18): (8-12): (0.3-0.7): (1-4).

9. The method for feeding high-selenium-enriched laying hens according to claim 1, characterized in that: The feeding method of the high-selenium-enriched laying hens is as follows: From hatching to 6 weeks of age, feed high-selenium-rich feed, 20-30g per day, 3-7 times a day, during which time they drink extract, 7-8 hours of light per day, light intensity of 10-14 lux. From 7-15 weeks of age, feed high-selenium-rich feed, 115-135g per day, 3-5 times a day, during which time they drink extract, 8-10 hours of light per day, light intensity of 5-9 lux. Finally, from 16-30 weeks of age, feed high-selenium-rich feed, 140-170g per day, 3-5 times a day, during which time they drink extract, 15-17 hours of light per day, light intensity of 10-15 lux.

10. A high-selenium-enriched egg, characterized in that: Produced by high-selenium-enriched laying hens fed using the feeding method for high-selenium-enriched laying hens described in any one of claims 1-9.