An animal feed prepared using a microbial fermentation product and a method of preparing the same

Abstract

This invention provides an animal feed prepared using microbial fermentation products and its preparation method. By constructing a symbiotic community of anaerobic ammonia-oxidizing bacteria and Clostridium butyricum, and combining it with livestock and poultry manure biochar as a fixation carrier and a complex enzyme system, the protein degradation and nitrogen emission control of ruminant feed are optimized. This method degrades crude protein into small peptides through anaerobic fermentation, while simultaneously converting ammonia nitrogen into nitrogen gas, effectively reducing ammonia emissions by 70%-80%. Furthermore, the use of high-temperature activated biochar as a fixation carrier improves the colonization rate and stability of the microbial community. This invention not only improves the nutrient utilization rate of feed but also solves the problems of high nitrogen emissions and low fiber utilization in traditional feeds, providing a novel solution for low-nitrogen, environmentally friendly ruminant feed.

Description

Technical Field

[0001] This invention belongs to the field of animal feed, specifically relating to an animal feed prepared using microbial fermentation products and its preparation method. Background Technology

[0002] In ruminant farming, low nitrogen utilization rate and high ammonia emissions are problems that the industry urgently needs to solve. Traditional ruminant feeds often improve nutrient conversion through single microbial agents or enzyme preparations. Although this can improve protein degradation, it is difficult to simultaneously achieve effective control of nitrogen emissions. Moreover, a large amount of unused nitrogen is released in the form of ammonia, which not only wastes resources but also causes the deterioration of the farming environment.

[0003] Currently, some technologies attempt to combine microbial-enzyme synergistic processes, but the compatibility of microbial communities is insufficient, and there is a lack of precise application targeting anaerobic denitrifying bacteria, resulting in limited ammonia nitrogen removal efficiency. Furthermore, conventional carriers such as straw charcoal and sawdust charcoal are often used in feed preparation, leading to low microbial colonization rates and poor stability, hindering the long-term effectiveness of microbial functions. In addition, livestock and poultry manure from large-scale farming is mostly treated as compost, resulting in low resource utilization and potential secondary pollution. Moreover, the insufficient degradation of fiber in traditional feed ingredients further limits the overall nutritional utilization rate of the feed. Therefore, developing a ruminant feed that balances efficient protein degradation, precise nitrogen emission control, and resource utilization of livestock waste, combining the synergistic effects of symbiotic microbial communities, complex enzyme systems, and environmentally friendly carriers, has become a development trend for low-nitrogen and environmentally friendly ruminant feeds, and is of great significance for promoting the green and efficient development of the livestock industry. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes an animal feed prepared using microbial fermentation products and its preparation method. This feed achieves efficient protein degradation, precise ammonia nitrogen removal, and resource utilization of livestock and poultry waste through the synergistic effect of symbiotic microbial communities, complex enzyme systems, and livestock and poultry manure biochar. It exhibits excellent performance in nutrient utilization, environmental protection and emission reduction, and microbial community stability, and can meet the application needs of large-scale green farming of ruminants.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An animal feed prepared using microbial fermentation products is composed of fermentation products obtained from symbiotic microbial fermentation materials and biochar from livestock and poultry manure. The feed is prepared from the following raw materials in parts by weight: 40-60 parts corn stalks, 10-20 parts soybean meal, and 0.1-0.3 parts compound enzyme system; The symbiotic microbial community is a combination of anaerobic ammonia-oxidizing bacteria and Clostridium butyricum, with an inoculation mass ratio of 1:(1.0-2.5), and the total inoculation amount is 5%-10% of the total mass of corn straw and soybean meal; The amount of biochar added from livestock and poultry manure is 5%-15% of the mass of the fermentation product; this feed can reduce ammonia emissions from ruminants by 70%-80%.

[0006] Optionally, the complex enzyme system is composed of microcrystalline cellulase, xylanase and pectinase, with a mass ratio of (1.5-2.5):(0.8-1.2):(0.4-0.6).

[0007] Optionally, the livestock and poultry manure biochar is obtained by high-temperature activation at 800-900℃, and its specific surface area is 300-400m2 / g.

[0008] Optionally, the feed contains 28%-35% small peptides and has an ammonia nitrogen removal rate of 88%-95%.

[0009] Optionally, the method for preparing animal feed using microbial fermentation products specifically includes the following preparation method: S1. Crush corn stalks to 40-80 mesh and soybean meal to 60-100 mesh. Mix them evenly in a mass ratio of (40-60):(10-20). Add deionized water to the mixture to adjust the moisture content to 55%-65%. Adjust the pH to 7.0-8.0 with a 5% sodium hydroxide solution or a 3% hydrochloric acid solution. Let it stand at room temperature for 1-2 hours for later use. S2. Spray the compound enzyme system evenly onto the pretreated raw materials and stir at 100-150 rpm for 10-15 minutes until the mixture is uniform. Then, inoculate the symbiotic community of anaerobic ammonia oxidizing bacteria and butyric acid clostridium, controlling the total inoculation amount to 5%-10% of the total mass of the raw materials. Transfer the mixture into a closed anaerobic fermenter, maintain the temperature inside the tank at 32-38℃ and the dissolved oxygen at 0.05-0.2 mg / L, and ferment for 24-36 hours. During this period, stir at 60-80 rpm once every 8 hours for 5-8 minutes each time. After the fermentation is completed, the fermentation product is obtained. S3. Cool the fermentation product to room temperature, add 5%-15% of the fermentation product mass of livestock and poultry manure biochar, stir at 120-180 rpm for 20-30 minutes until uniformly mixed, granulate using a low-temperature granulator, control the granulation temperature at 50-60℃ and the particle size at 3-5mm, and dry at a low temperature of 45-55℃ until the moisture content is 8%-12% to obtain the animal feed.

[0010] Optionally, in step S1, the corn stalks and soybean meal are crushed and then screened using a 100-mesh standard sieve, with the utilization rate of the undersize material being 90%-98%.

[0011] Optionally, in step S2, the internal pressure of the sealed anaerobic fermenter is controlled at 0.05-0.1 MPa.

[0012] Optionally, the low-temperature drying time in step S3 is 2-4 hours, and the water activity of the dried feed is 0.6-0.7.

[0013] The beneficial effects of this invention are as follows: The animal feed prepared by this invention has excellent environmental protection and emission reduction effects, reducing ammonia emissions from ruminants by 70%-80% and achieving an ammonia nitrogen removal rate of 88%-95%, effectively improving the breeding environment; the feed contains 28%-35% small peptides, and the compound enzyme system and symbiotic bacteria synergistically promote fiber degradation and protein conversion, significantly improving nutrient utilization; the porous structure of livestock and poultry manure biochar enhances the colonization rate and stability of the microbial community, realizing the resource utilization of breeding waste; at the same time, the feed has good formability, long shelf life, and excellent compatibility with the rumen environment of ruminants, which can take into account both breeding efficiency and environmental protection needs, solving the core problems of low nitrogen utilization, serious pollution, and insufficient resource utilization of waste in traditional feed. Attached Figure Description

[0014] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0015] Figure 1 This is a comparison chart of the core functional indicators of denitrification and nutrient conversion in different feed samples of the present invention. Figure 2 This is a comparison chart of the core indicators of microbial colonization stability in different feed samples according to the present invention. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0017] Example 1: An animal feed prepared using microbial fermentation products according to Example 1 is prepared from the following raw materials in parts by weight: 50 parts corn stalks, 15 parts soybean meal, and 0.2 parts compound enzyme system (microcrystalline cellulase: xylanase: pectinase = 2:1:0.5); This embodiment describes a method for preparing animal feed using microbial fermentation products. The specific preparation steps are as follows: S1. Crush corn stalks to 60 mesh and soybean meal to 80 mesh, mix them evenly at a mass ratio of 50:15, add deionized water to adjust the moisture content to 60%, adjust the pH to 7.5 with a 5% sodium hydroxide solution, and let stand at room temperature for 1.5 hours before use; after crushing, screen through a 100-mesh standard sieve, with a sieve-through rate of 95%; S2. Spray the compound enzyme system into the pretreated raw materials and stir at 120 rpm for 12 min until the mixture is uniform. Then inoculate anaerobic ammonia oxidizing bacteria and Clostridium butyricum at a mass ratio of 1:1.5. Control the total inoculation amount to 8% of the total mass of corn straw and soybean meal. Transfer the mixture into a closed anaerobic fermenter and maintain the temperature inside the tank at 35℃, pressure at 0.08 MPa, and dissolved oxygen at 0.1 mg / L. Ferment for 30 h, stirring at 70 rpm for 6 min every 8 h to obtain the fermentation product. S3. Take fresh manure from a large-scale beef cattle farm, air dry it naturally until the moisture content is ≤20%, crush it to 40 mesh, and then transfer it to a tube furnace. Under nitrogen protection, heat it to 850℃ at a heating rate of 10℃ / min, keep it at a constant temperature for 2 hours, cool it down, and crush it to 80 mesh to obtain livestock and poultry manure biochar. S4. Cool the fermentation product to room temperature, add 10% of the fermentation product mass of livestock and poultry manure biochar, stir at 150 rpm for 25 minutes until evenly mixed, granulate using a low-temperature granulator at 55℃ and a particle size of 4 mm, and dry at 50℃ for 3 hours until the moisture content is 10% to obtain the finished product.

[0018] Comparative Example 1: The feed for Comparative Example 1 was prepared from the following parts by weight of raw materials: 50 parts corn stalks, 15 parts soybean meal, and 0.2 parts compound enzyme system (microcrystalline cellulase: xylanase: pectinase = 2:1:0.5); The feed preparation method in this comparative example is the same as in Example 1, except that only Clostridium butyricum is used and anaerobic ammonia-oxidizing bacteria are removed. The total inoculum amount is 8% of the total mass of corn stalks and soybean meal.

[0019] Comparative Example 2: The feed for Comparative Example 2 was prepared from the following parts by weight of raw materials: 50 parts corn stalks, 15 parts soybean meal; The feed preparation method in this comparative example is the same as in Example 1, without the addition of compound enzymes.

[0020] Comparative Example 3: The feed for Comparative Example 3 was prepared from the following parts by weight of raw materials: 50 parts corn stalks, 15 parts soybean meal, and 0.2 parts compound enzyme system (microcrystalline cellulase: xylanase: pectinase = 2:1:0.5); The feed preparation method in this comparative example is the same as in Example 1, except that straw biochar is used instead of livestock and poultry manure biochar. The preparation method of straw biochar is as follows: take corn straw, dry it naturally until the moisture content is ≤20%, crush it to 40 mesh, and then transfer it to a tube furnace. Under nitrogen protection, the temperature is raised to 850°C at a heating rate of 10°C / min, and activated at a constant temperature for 2 hours. After cooling, crush it to 80 mesh to obtain straw biochar.

[0021] Performance testing 1. Tests on ammonia nitrogen removal rate and reduction rate of ammonia emissions from ruminants Take 5g each of the raw material mixture before fermentation and the product after fermentation in Examples 1 and Comparative Examples 1-3, add deionized water at a material-to-liquid ratio of 1:10, shake and extract for 30 min, centrifuge at 4000 rpm for 10 min, and collect the supernatant. Refer to HJ 535-2009 "Determination of Ammonia Nitrogen in Water - Nessler's Reagent Spectrophotometric Method", first remove turbidity and color interference in the sample by flocculation and sedimentation, then add Nessler's reagent for color development, and measure the absorbance at 420 nm wavelength using a 20 mm cuvette with water as a reference. Convert the ammonia nitrogen concentration using the standard curve, and finally calculate the ammonia nitrogen removal rate of each group according to the formula "Removal rate = (Ammonia nitrogen concentration before fermentation - Ammonia nitrogen concentration after fermentation) / Ammonia nitrogen concentration before fermentation × 100%". Set up 3 parallel samples for each group, and take the average value of the results to ensure data reliability.

[0022] Table 1. Test data on nitrogen removal rate and reduction rate of ammonia emissions from ruminants for different samples.

[0023] Example 1 showed an ammonia nitrogen removal rate of 92% and a 75% reduction in ammonia emissions from ruminants, significantly higher than the comparative examples (ammonia nitrogen removal rate 55%-80%, ammonia emission reduction rate 42%-63%). This result fully validates the synergistic effect of anaerobic ammonia-oxidizing bacteria and Clostridium butyricum, the auxiliary degradation effect of the complex enzyme system, and the synergistic denitrification system formed by the efficient adsorption and fixation function of livestock and poultry manure biochar, which fundamentally solves the industry pain point of severe ammonia pollution in traditional feed.

[0024] 2. Small peptide content and crude fiber degradation rate test Take 5g of each of the feed products from Example 1 and Comparative Examples 1-3. Following the spectrophotometric method in GB / T 22492-2008 "Soybean Peptide Powder," after defatting and protein removal pretreatment, precipitate large molecular weight proteins using trichloroacetic acid. Separate the small peptide components (molecular weight <3000Da) from the supernatant using gel filtration chromatography. Add Folin-phenol reagent for color development and measure the absorbance at 680nm. Calculate the small peptide content using the tyrosine standard curve. Simultaneously, take 2g each of the pre-fermentation raw material mixture and the finished feed product from each group, and follow GB / T... According to 6434-2006 "Determination of Crude Fiber in Feed - Filtration Method", the feed is defatted with petroleum ether, boiled in 1.25% sulfuric acid solution for 30 min, and boiled in 1.25% sodium hydroxide solution for 30 min. After filtration in a Gooch crucible, the feed is dried at 130℃ to constant weight. The crude fiber residue is calculated. The degradation rate is calculated according to the formula "Crude fiber degradation rate = (Crude fiber content before fermentation - Crude fiber content after fermentation) / Crude fiber content before fermentation × 100%". Three parallel samples are set up for each group. The relative deviation of the parallel samples is ≤3%. The average value of the results is taken to ensure the reliability of the data.

[0025] Table 2. Test data on small peptide content and crude fiber degradation rate of different samples.

[0026] Example 1 showed a crude fiber degradation rate of 65% and a small peptide content of 32% in the finished feed, both superior to the comparative examples (crude fiber degradation rate 37%-56%, small peptide content 21%-29%). The experiment confirmed that the synergistic effect of the complex enzyme system and symbiotic bacteria can efficiently break down the crude fiber structure and promote the conversion of crude protein into small molecule active peptides. Livestock and poultry manure biochar provided a stable microenvironment for the synergistic effect of bacteria and enzymes, significantly improving the utilization rate of feed nutrients.

[0027] 3. Microbial colonization stability test 10g of each of the finished feed products from Example 1 and Comparative Examples 1-3 were taken, and the viable bacterial count was detected using the serial dilution plate count method. Anaerobic ammonia oxidizing bacteria were cultured on AMO-specific anaerobic medium, and Clostridium butyricum on RS-specific anaerobic medium. After 7 days of incubation in an anaerobic incubator at 37℃, the viable bacterial count was recorded. At the same time, 8 healthy beef cattle with rumen fistulas were randomly divided into 4 groups corresponding to each experimental group, with 2 cattle in each group. After feeding the corresponding feed, 50mL of rumen fluid was collected on the 7th and 14th days, and after serial dilution, plate counts were performed using the same culture medium and incubation conditions as described above to calculate the colonization rate of rumen flora. In addition, the finished feed products of each experimental group were stored in a sealed environment at 25℃ and 60% relative humidity for 30 days, and samples were taken to detect the viable bacterial count and calculate the viable bacterial retention rate. This was used to comprehensively evaluate the stability of flora colonization. All tests were conducted with 3 parallel samples, and the relative deviation of parallel samples was ≤5%. The average value of the results was used to ensure the reliability of the data.

[0028] Table 3. Data on the colonization stability of different bacterial communities in different samples.

[0029] In Example 1, the viable bacterial retention rate reached 82% after 60 days of storage, and the rumen microbiota colonization rate remained at 85% on day 14, significantly higher than the comparative studies (53%-68% viable bacterial retention rate at 60 days and 58%-75% rumen colonization rate at 14 days). This indicates that livestock manure biochar, with its unique porous structure, can effectively immobilize microbiota, reduce inactivation losses during storage, and promote microbial colonization and reproduction in the rumen. Its carrier advantages are significantly superior to straw biochar and single-microbiota systems.

[0030] 4. Basic physical properties and storage stability tests Take 20g of each of the finished feed products from Example 1 and Comparative Examples 1-3, and sieve them using a three-layer standard test sieve (4mm, 3mm, and 2mm). After shaking for 10 minutes, weigh the mass of particles remaining in each sieve layer and calculate the proportion of particles of different sizes to determine the particle size distribution. Randomly select 50 pellets of shaped feed from each group and measure the single-particle crushing resistance using a pellet hardness tester, taking the average value as the pellet hardness value. Take 5g of each finished feed product and dry it to constant weight at 105℃ using a constant temperature drying method, calculate the moisture content, and simultaneously measure the feed water activity directly with a water activity meter to complete the baseline analysis. Basic physical property tests were conducted. Additionally, the finished feed products from each experimental group were sealed and placed in an environment of 25℃ and 60% relative humidity for storage stability tests. Samples were taken after 30 and 60 days of storage, and the above methods for testing moisture content and water activity were repeated. The feed was visually inspected for mold growth and clumping. Storage stability was comprehensively evaluated by combining the changes in viable bacterial count and small peptide content after 30 and 60 days of storage. All tests were performed with three parallel samples. The relative deviation of the parallel samples for physical property testing was ≤3%, and the average value was used to ensure data reliability.

[0031] Table 4. Test data of basic physical properties of different samples

[0032] Table 5. Data on storage stability of different samples

[0033] Example 1 showed a core particle size ratio of 96.2%, a particle hardness of 42N, excellent physical formability, no mold growth after 60 days of storage, and a small peptide retention rate of 95%, exhibiting superior overall stability compared to the comparative examples. Experiments confirm that the addition of livestock and poultry manure biochar not only optimizes the physical properties of the feed, making it suitable for large-scale mechanical feeding, but also regulates feed moisture, inhibits mold growth, and ensures stable nutrient composition during storage, demonstrating significant industrial application value.

[0034] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An animal feed prepared using microbial fermentation products, characterized in that, The feed is prepared by combining the fermentation product obtained from the fermentation of symbiotic microbial communities with livestock and poultry manure biochar. The feed is prepared from the following raw materials in parts by weight: 40-60 parts corn stalks, 10-20 parts soybean meal, and 0.1-0.3 parts compound enzyme system; The symbiotic microbial community is a combination of anaerobic ammonia-oxidizing bacteria and Clostridium butyricum, with an inoculation mass ratio of 1:(1.0-2.5), and the total inoculation amount is 5%-10% of the total mass of corn straw and soybean meal; The amount of biochar added from livestock and poultry manure is 5%-15% of the mass of the fermentation product; this feed can reduce ammonia emissions from ruminants by 70%-80%.

2. The animal feed prepared using microbial fermentation products according to claim 1, characterized in that, The complex enzyme system consists of microcrystalline cellulase, xylanase, and pectinase, with a mass ratio of (1.5-2.5):(0.8-1.2):(0.4-0.6).

3. The animal feed prepared using microbial fermentation products according to claim 1, characterized in that, The biochar made from livestock and poultry manure is obtained by high-temperature activation at 800-900℃, and its specific surface area is 300-400m2 / g.

4. The animal feed prepared using microbial fermentation products according to claim 1, characterized in that, The feed contains 28%-35% small peptides and has an ammonia nitrogen removal rate of 88%-95%.

5. A method for preparing animal feed using microbial fermentation products, used to prepare the animal feed using microbial fermentation products according to any one of claims 1-4, characterized in that, The specific preparation method is as follows: S1. Crush corn stalks to 40-80 mesh and soybean meal to 60-100 mesh. Mix them evenly in a mass ratio of (40-60):(10-20). Add deionized water to the mixture to adjust the moisture content to 55%-65%. Adjust the pH to 7.0-8.0 with a 5% sodium hydroxide solution or a 3% hydrochloric acid solution. Let it stand at room temperature for 1-2 hours for later use. S2. Spray the compound enzyme system evenly onto the pretreated raw materials and stir at 100-150 rpm for 10-15 minutes until the mixture is uniform. Then, inoculate the symbiotic community of anaerobic ammonia oxidizing bacteria and butyric acid clostridium, controlling the total inoculation amount to 5%-10% of the total mass of the raw materials. Transfer the mixture into a closed anaerobic fermenter, maintain the temperature inside the tank at 32-38℃ and the dissolved oxygen at 0.05-0.2 mg / L, and ferment for 24-36 hours. During this period, stir at 60-80 rpm once every 8 hours for 5-8 minutes each time. After the fermentation is completed, the fermentation product is obtained. S3. Cool the fermentation product to room temperature, add 5%-15% of the fermentation product mass of livestock and poultry manure biochar, stir at 120-180 rpm for 20-30 minutes until uniformly mixed, granulate using a low-temperature granulator, control the granulation temperature at 50-60℃ and the particle size at 3-5mm, and dry at a low temperature of 45-55℃ until the moisture content is 8%-12% to obtain the animal feed.

6. The method for preparing animal feed using microbial fermentation products according to claim 5, characterized in that, In step S1, the corn stalks and soybean meal are crushed and then screened using a 100-mesh standard sieve, with the utilization rate of the undersize material being 90%-98%.

7. The method for preparing animal feed using microbial fermentation products according to claim 5, characterized in that, In step S2, the pressure inside the sealed anaerobic fermenter is controlled at 0.05-0.1 MPa.

8. The method for preparing animal feed using microbial fermentation products according to claim 5, characterized in that, The low-temperature drying time in step S3 is 2-4 hours, and the water activity of the dried feed is 0.6-0.7.

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