Lactobacillus brevis with deodorization and growth promotion functions and application of lactobacillus brevis

Abstract

The invention provides lactobacillus brevis with deodorization and growth promotion functions and application of the lactobacillus brevis. The lactobacillus brevicornu SQ13 is preserved in the China General Microbiological Culture Collection Center (CGMCC), and the preservation number is CGMCC No.31018. The lactobacillus brevicornu SQ13 can be used for preparing lactobacillus brevicornu. The lactobacillus brevis provided by the invention is screened from faeces of healthy growing pigs, and has good acid resistance, cholate resistance, antibacterial activity and ammonia and sulfur removal capability. The invention also discloses a preparation containing the lactobacillus brevis SQ13. The feed containing the lactobacillus brevis SQ13 can effectively improve the production performance of animals and reduce the odor emission of excrement, for example, a preparation containing the lactobacillus brevis SQ13 is used for feeding growing pigs, so that the intestinal health of the growing pigs can be improved, the production performance and the immune function can be improved, the concentration of NH3 and H2S in the excrement can be reduced, the healthy growth of the growing pigs can be promoted, and the growth of the growing pigs can be promoted. Good development and application prospects are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of microorganisms, and in particular relates to a Lactobacillus curvatus with deodorizing and growth-promoting functions and an application thereof. Background Art

[0002] With the development of large-scale and intensive pig farming in my country, feed antibiotics and farm odor (mainly NH 3 and H 2 The problem of s) has attracted much attention. It not only causes drug residues, the decline of pig immunity and production performance, but also causes odor pollution, which seriously harms animal health, human health and the ecological environment. It has become a key issue restricting the high-quality and sustainable development of the industry. How to develop new feed additives with good growth promotion and odor reduction has become a hot spot in the current feed industry research and development.

[0003] Latilactobacillus curvatus, formerly known as Lactobacillus curvatus, is a Gram-positive, non-spore-forming, facultatively anaerobic, curvy bean-shaped rod-shaped bacterium that often appears in pairs or short chains. The colonies are raised, opaque, and milky white. Latilactobacillus curvatus has good fermentation properties and was approved as a new food ingredient for fermented meat products, fermented milk and dairy products in 2019. At present, the patents related to Lactobacillus curvatus include: Patent application publication number CN 116426417A, entitled "Lactobacillus curvatus LC02 and its application in the preparation of drugs for treating or preventing allergic diseases", which can inhibit the degranulation of mast cells or basophils in the body and has the potential to be used in the body to treat or prevent allergic reactions; Patent application publication number CN 114874954A, entitled "A Lactobacillus curvatus capable of promoting the production of short-chain fatty acids in the intestine and its application", which discloses a Lactobacillus curvatus capable of promoting the production of short-chain fatty acids in the intestine and its application, which can be used as food or medicine; Patent application publication number CN 117448191A, entitled "A strain of Lactobacillus curvatus with antioxidant ability and its application", which can be used as a health food or medicine to improve the body's immunity, anti-aging, beauty and regulate intestinal flora; Patent application publication number CN 113025539A, entitled "A strain of salt-tolerant and low-temperature-resistant Lactobacillus curvatus that inhibits pathogens and its application in repeated freeze-thaw storage in the cold chain of food", the strain is resistant to low temperatures and high salts, and can be used to inhibit a variety of low-temperature-resistant or high-salt-resistant pathogens, and can be used for refrigerated preservation, slightly frozen preservation or frozen preservation products under repeated freeze-thaw; Patent application publication number CN 113373084A, entitled "An antibacterial and extracellular polysaccharide-producing Lactobacillus curvatus and its application", discloses a strain of Lactobacillus curvatus SJTUF 62116 that has both broad-spectrum antibacterial function and can produce extracellular polysaccharides with biological activity, and can be widely used in the fields of antibacterial and antioxidant. The above Lactobacillus curvatus is mainly used in the preparation of human food, health products and medicines. At present, there is no research and application of Lactobacillus curvatus in pig breeding and production. Summary of the invention

[0004] The object of the present invention is to provide a kind of Lactobacillus benthamianus and its application. The Lactobacillus benthamianus is screened from healthy pig feces, has good acid and bile salt resistance, strong antibacterial performance, and strong ammonia nitrogen (NH 4 + -N) and S 2- Feeding growing pigs with this fermented feed with Lactobacillus curvatus can improve their intestinal health, production performance and immune function, and significantly reduce fecal NH 3 and H 2 S concentration, promoting the healthy growth of growing pigs.

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

[0006] Latilactobacillus curvatus SQ13, the strain was deposited in the General Microbiology Center of China Culture Collection Administration on June 19, 2024, with the deposit number: CGMCC No.31018.

[0007] A feed additive containing the above-mentioned Lactobacillus curvatum.

[0008] The feed additive as described above is preferably a fermented feed additive.

[0009] A feed containing the above-mentioned Lactobacillus curvatum or the feed additive. Further, preferably, the feed is a fermented feed.

[0010] The method for preparing the fermented feed additive as described above comprises fermenting the feed with the Lactobacillus curvatum as described above. Preferably, the Lactobacillus curvatum is inoculated into the feed, mixed and compacted, and then sealed and fermented at a constant temperature to obtain the fermented feed additive.

[0011] Furthermore, the constant temperature fermentation temperature is 37° C., and the fermentation is carried out for 24 hours.

[0012] A feed additive, comprising the Lactobacillus curvatum as described above.

[0013] As mentioned above, fermented feed additives or feed additives are used to improve animal production performance and reduce odor emissions.

[0014] Further, improving animal production performance is to increase the daily weight gain of pigs, and reducing odor emissions is to reduce fecal NH 3 and H 2 S.

[0015] Preferably, the fermented feed additive is added in an amount of 0.25-1% of the diet. Further, the fermented feed additive is added in an amount of 0.3% of the diet.

[0016] The use of the Lactobacillus curvatum as described above in the preparation of an animal breeding deodorant.

[0017] A feed for reducing odor in animal breeding, comprising the above-mentioned Lactobacillus curvatum.

[0018] The beneficial effects of the present invention are:

[0019] The Latilactobacillus curvatus SQ13 provided by the present invention is a strain with good growth performance and strong acid and bile resistance, and has strong antibacterial performance, which can effectively improve the production performance of animals and reduce fecal odor emissions. The feed fermented by the Latilactobacillus curvatus is added as an additive to the feed of growing pigs, which can significantly increase the average daily weight gain of the pigs and reduce the feed-to-weight ratio; significantly increase the number of lactic acid bacteria in the feces of growing pigs, significantly reduce the number of Escherichia coli, and significantly reduce NH 3 and H 2 S concentration; significantly increase serum total protein, immunoglobulin G, immunoglobulin M and immunoglobulin A contents, significantly reduce urea nitrogen, triglyceride contents and alanine aminotransferase activity, have the effects of inhibiting the reproduction of harmful bacteria, regulating intestinal microecological balance, reducing odor concentration in feces, enhancing body immunity and improving production performance, etc., have good economic value and good development and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a photo of the colony morphology of Lactobacillus curvatus SQ13.

[0021] Figure 2 This is the Gram staining image of Lactobacillus curvatus SQ13.

[0022] Figure 3 This is the growth curve of Lactobacillus curvatus SQ13.

[0023] Figure 4 This is a diagram of lactic acid production by Lactobacillus curvatus SQ13. DETAILED DESCRIPTION

[0024] The following examples are used to further illustrate the present invention, but should not be construed as limiting the present invention. Without departing from the spirit and substance of the present invention, modifications or substitutions made to the present invention all belong to the scope of the present invention.

[0025] Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents used in the following examples of the present invention are all analytically pure or above.

[0026] Example 1 Isolation, screening and identification of Lactobacillus curvatus

[0027] 1. Isolation and identification of strains

[0028] Collect fresh feces from growing pigs, weigh 25g and place in a glass beaded flask containing 225mL of sterile saline, shake evenly and make ten-fold gradient dilutions. -4 , 10 -5 , 10-6 Three dilutions were prepared. 0.1 mL of bacterial solution was taken from each dilution and spread on MRS medium plates (Beijing Aoboxing). The plates were cultured in anaerobic jars at 37°C for 24 to 48 hours. Milky white colonies were selected for preliminary screening. Gram-positive, H 2 O 2 The strains with negative enzyme test can be preliminarily identified as lactic acid bacteria. The activated strains were inoculated into ammoniation medium (Shandong Top Biotechnology) and sulfur bacteria medium (Qingdao Haibo Biotechnology) at a volume ratio of 1%, and the viable bacteria were counted after culturing at 37°C for 24 hours, and NH 4 + -N, S 2- The concentration was measured to observe the growth performance and ammonia and sulfur removal capabilities of the strain, and the strain was preliminarily identified by 16S rDNA sequencing. The calculation formula is as follows:

[0029] NH 4 + -N removal rate = (initial ammonia nitrogen concentration of culture medium - final ammonia nitrogen concentration of culture medium) / initial ammonia nitrogen concentration of culture medium × 100%; S 2- Removal rate = (initial S 2- Concentration - Final S 2- concentration) / initial S of medium 2- Concentration × 100%.

[0030] The primers used for molecular biology PCR amplification were: 27F (SEQ ID NO.1: 5'-AGAGTTTGATCCTGGCTCAG-3') and 1492R (SEQ ID NO.2: 5'-TACGACTTAACCCCAATCGC-3').

[0031] Through the above operation, a total of 10 strains of Latilactobacillus curvatus with the ability to remove ammonia and sulfur were screened out. The results are shown in Table 1. Among the 10 strains of Latilactobacillus curvatus, the number of viable bacteria of the strain numbered SQ13 after 24 hours of growth was 3.5×10 9 CFU / mL, NH 4 + -N removal rate is 38.5%, S 2- The removal rate was 21.8%, the highest among all, showing good growth performance and ammonia and sulfur removal capabilities. It was sent to the General Microbiological Center of China Microbiological Culture Collection Administration (CGMCC) for identification of cell morphological characteristics, physiological and biochemical characteristics and 16S rDNA sequence. The curved broad-spreading lactobacillus was grown in MRS medium and cultured anaerobically at 37℃ for 24h. The colonies were white, round, moist, opaque, and had neat edges. Figure 1The bacteria are rod-shaped, arranged singly, in pairs or in chains, Gram-positive, and oxidase-positive, such as Figure 2 As shown, the strain SQ13 was determined to be Latilactobacillus curvatus. Its physiological and biochemical characteristics are shown in Table 2. The sequencing result of the amplified product is shown in SEQ ID NO.3.

[0032] Table 1 Screening results of Lactobacillus curvatus

[0033]

[0034] Table 2 Physiological and biochemical characteristics of Lactobacillus curvatus SQ13

[0035]

[0036]

[0037] Note: “+” means positive; “–” means negative.

[0038] 16S rDNA region SEQ ID NO.3: ATTGAAGAAGCTTGCTTCTGATTGA TAACATTTGAGTGAGTGGCGGACGGGTGAGTAACACGTGGGTAACCTGCCCTAAAGTGGGGGATAACATTTGGAAACAGATGCTAATACCGCATAAAACCTAGCACCGCATGGTGCAAGGTTCAAAGATGGTTTCGGCTATCACTTTAGGATGGACCCGCGGTGCATTAGTTAGTTGGTGAGGTAAAGGCTCACCAAGACCGTGATGCATAGCCGACCTGAGAGGGTAATCGGCCACACTGGGACTGAGACACGGCCCAGACTCCTACGGGAGGCAGCAGTAGGGAATCTTCCACAATGGACGAAAGTCTGATGGAGCAACGCCGCGTGAGTGAAGAAGGTTTTCGGATCGTAAAACTCTGTTGTTGGAGAAGAACGTATTTGATAGTAACTGATCAGGTAGTGACGGTATCCAACCAGAAAGCCACGGCTAACTACGTGCCAGCAGCCGCGGTAATACGTAGGTGGCAAGCGTTGTCCGGATTTATTGGGCCTAAAGCGAGCGCAGGCGGTTTCTTAAGTCTGATGTGAAAGCCTTCGGCTCAACCGAAGAAGTGCATCGGAAACGGGAAACTTGAGTGCAGAAGAGGACAGTGGAACTCCATGTGTAGCGGTGAAATGCGTAGATATATGGAAGAACACCAGTGGCGAAGGCGGCTGTCTGGTCTGTAACTGACGCTGAGGCTCGAAAGCATGGGTAGCAAACAGGATTACATACCCTGGTAGTCCATGCCGTAAACGATGAGTGCTAGGTGTTGGAGGGTTTCCGCCCTTCAGTGCCGCAGCTAACGCATTAAGCACTCCGCCTGGGGAGTACGACCGCAAGGTTGAAACTCAAAGGAATTGACGGGGGCCCGCACAAGCGGTGGAGCATGTGGTTTAATTCGAAGCAACGCGAAGAACCTTACCAGGTCTTGACATCCTTTGACCACTCTACAGATAGAGCTTTCCCTTCGGGGACAAAGTGACAGGTGGTGCATGGTTGTCGTCAGCTCGTGTCGTGAGATGTTGCGTTAAGTCCCGCAACGAGCGCAACCCTTATTACTAGTTGCCAGCATTTAGTTGGGCACTCTAGTGAGACTGCCGGTGACAAACCGGAGGAAGGTGGGGACGACGTCAAATCATCATGCCCCTTATGACCTGGGCTACACACGTGCTAC AATGGATGGTACAACGAGTCGCGAGACCGCGAGGTTTAGCTAATCTCTTAAAACCATTCTCAGTTCGGATTGTAGCCTGCAACTCGCCTACATGAAGCCGGAATCGCTAGTAATCGCGGATCAGCATGCCGCGGTGAATACGTTCCCGGGCCTTGTACACACCGCCCGTCACACCATGAGAGTTTGTAACACCCAAAGCCGGTGAGGT.

[0039] The strain SQ13 was sent to the General Microbiology Center of China Culture Collection Administration Committee for Microbiological Culture Collection (address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, Postal Code: 100101) for patent deposit on June 19, 2024, with deposit number: CGMCC No.31018, deposit name: SQ13, classification name: Latilactobacillus curvatus.

[0040] Example 2 Study on the characteristics of Lactobacillus curvatus SQ13

[0041] 1. Curved growth curve of Lactobacillus sQ13

[0042] After activation, Lactobacillus curvatus SQ13 was inoculated into MRS liquid medium (Beijing Aoboxing) at inoculation amounts of 0.5% (v / v), 1% (v / v), 2% (v / v), 3% (v / v), and 5% (v / v), respectively, and cultured at 37°C for 48 h. The OD600nm value of the bacterial solution from 0 to 48 h was measured using an automatic growth curve analyzer Bioscreen C (Oy Growth Curves Ab Ltd., Finland), and the growth curve was drawn. The results are shown in Figure 3 As shown. From the growth curve ( Figure 3) It can be seen that Lactobacillus curvatus SQ13 grows rapidly into the logarithmic growth phase 2 hours after inoculation and enters the stable phase after 12 hours; the inoculation amount is 1%, 2% and 3% and the optimal inoculation amount is determined to be 1% after comprehensive consideration.

[0043] 2. Acid resistance of Lactobacillus curvatus SQ13

[0044] Liquid MRS medium containing 1% pepsin at pH 3 and 4 was prepared to simulate the gastric acid environment of animals, and the acid resistance of Lactobacillus curvatus SQ13 was measured. The Lactobacillus curvatus SQ13 obtained in Example 1 after activation twice was inoculated into the above culture medium at a volume ratio of 1%, and acted at 37°C for 2h and 4h, respectively. The number of viable bacteria was measured with 0h as the control, and the tolerance was calculated according to the formula: survival rate (%) = number of viable bacteria after different hours of action / number of viable bacteria at 0h × 100. The results are shown in Table 3.

[0045] Table 3 Tolerance of Lactobacillus curvatus SQ13 to gastric acid (%)

[0046]

[0047] The test results show that the survival rate of this Lactobacillus benthamiana in an acidic environment of pH = 3 for 2 hours is 39.84%, and the survival rate for 4 hours is 20.98%; the survival rate for 2 hours in an acidic environment of pH = 4 is 78.46%, and the survival rate for 4 hours is 91.06%. The above results show that the Lactobacillus benthamiana SQ13 obtained by the present invention can tolerate an acidic environment of pH 4 and has a strong tolerance to gastric acid of animals.

[0048] 3. Bile salt tolerance of Lactobacillus curvatus SQ13

[0049] Liquid MRS culture medium containing 0.05%, 0.1%, and 0.2% pig bile salts was prepared to simulate the intestinal environment of animals, and the bile salt tolerance of Lactobacillus curvatus SQ13 was determined. Lactobacillus curvatus SQ13 activated twice was inoculated in the above culture medium at a volume ratio of 1%, and acted at 37°C for 2h and 4h, respectively, with 0h as the control. The tolerance was calculated according to the formula: survival rate (%) = number of viable bacteria after different hours of action / number of viable bacteria at 0 hour × 100. The test results are shown in Table 4.

[0050] Table 4 Tolerance of Lactobacillus curvatus SQ13 to bile salts (%)

[0051]

[0052] The results show that this curved widespread lactobacillus SQ13 has a high tolerance to 0.05% and 0.1% bile salts, with survival rates of 107.27%, 83.%, 97.27% and 77.59% after 2h and 4h respectively, while the survival rate at 0.2% bile salt concentration is only 3.5% and 1.5%. The above results show that this curved widespread lactobacillus can tolerate a 0.1% bile salt environment and has a strong tolerance to animal intestinal bile salts.

[0053] 4. Antibacterial test of Lactobacillus curvatus SQ13

[0054] The Oxford cup method was used to detect the antibacterial effect of the culture solution of Lactobacillus curvatus SQ13 on three common swine pathogens (Escherichia coli, Salmonella cholerae, and Staphylococcus aureus, all purchased from the China Veterinary Drug Administration). The three pathogens were activated and diluted to a concentration of 10 7 CFU / mL, 100 μL of culture solution was evenly spread on MacConkey medium, Salmonella medium and Baird-Parker medium plates, and placed in a sterile Oxford cup after standing for 30 minutes, and then 180 μL of Lactobacillus curvatus SQ13 fermentation solution cultured at 37°C for 24 hours was added. The antibacterial diameter was determined after standing at 37°C, and the results are shown in Table 5.

[0055] Table 5 Antibacterial test of Lactobacillus curvatus SQ13

[0056]

[0057] From the results in Table 5, it can be seen that the diameters of the inhibition zones of Lactobacillus curvatus SQ13 against porcine Escherichia coli, Salmonella cholerae and Staphylococcus aureus are 31.8, 34.3 and 30.8 mm, respectively, indicating that it has a strong antibacterial effect.

[0058] 5. Drug sensitivity test of Lactobacillus curvatus SQ13

[0059] The antibiotic microbial susceptibility test was performed using the agar diffusion method. The susceptibility test of Lactobacillus curvatus SQ13 was performed on 20 antibiotics from 10 categories (OXOID susceptibility paper sheets), and the results are shown in Table 6.

[0060] Table 6 Drug sensitivity test of Lactobacillus curvatus SQ13

[0061]

[0062]

[0063] Note: S stands for sensitive; I stands for moderately sensitive; R stands for resistant.

[0064] As can be seen from Table 6, this Lactobacillus curvatus is sensitive to antibiotics such as ampicillin, ceftizoxime, cefprozil, cefotaxime, clindamycin, florfenicol, erythromycin, azithromycin and amoxicillin, moderately sensitive to lincomycin, and resistant to antibiotics such as streptomycin, amikacin, ofloxacin, gentamicin, enrofloxacin, ofloxacin, ciprofloxacin, chloramphenicol, colistin sulfate, sulfamethoxazole and tetracycline.

[0065] 6. Lactic acid production test of Lactobacillus curvatus SQ13

[0066] The activated twice Lactobacillus curvatus SQ13 was inoculated into the liquid MRS medium at a volume ratio of 1%, and the lactic acid content in the fermentation broth was detected using a lactic acid detection kit. The results are shown in Figure 4 .Depend on Figure 4 It can be seen that with the extension of culture time, Lactobacillus curvatus SQ13 grew rapidly in MRS medium, and the lactic acid content it produced also increased rapidly, reaching a maximum of 73.81 mmol / L at 32 h, and then the acid production tended to stabilize.

[0067] Example 3 Application of Lactobacillus curvatus fermented feed in growing pig production

[0068] Preparation of fermented feed using Lactobacillus curvatus SQ13: freeze-dried preparation of Lactobacillus curvatus SQ13 (which can be prepared by conventional methods, containing 6.05×10 9 CFU / g), drinking water and complete feed for growing pigs (corn-soybean meal type) are mixed at a weight ratio of 1:100:100, stirred evenly, and then put into a clean plastic bucket, compacted, and sealed with a cover; the feed bucket is placed in a constant temperature incubator and cultured at 37°C for 24 hours before being opened for use to obtain fermented feed. At the same time, the isolated Lactobacillus curvatus SQ18 strain is selected to prepare fermented feed using the same method.

[0069] A total of 90 healthy growing pigs were randomly divided into 3 groups, with 3 replicates in each group and 10 pigs in each replicate. The control group was fed a basal diet, and the experimental group 1 was fed a basal diet supplemented with 0.3% SQ13 fermented feed (the final effective viable count in the complete feed was 5.19×10 7 CFU / g), and the second group added 0.4% SQ18 fermented feed to the basal diet (the final effective viable count in the complete feed was 5.2×10 7CFU / g). The basal diet consists of corn, soybean meal, wheat bran, calcium hydrogen phosphate, stone powder, amino acids, vitamins, trace elements, etc. The nutritional level is formulated in accordance with the "Nutritional Requirements of Pigs" (GB / T 39235-2020). The pigs were fed for 32 consecutive days, with free access to food and water, and routine immunization. Other feeding management and immunization procedures were carried out in a unified manner according to large-scale pig farms. Fasting weights were carried out at the beginning and end of the experiment, and the daily feed consumption was recorded to calculate the average daily weight gain, average daily feed intake and feed-to-weight ratio; after the end of the experiment, 3 fresh fecal samples were randomly collected from each replicate to determine the number of live lactic acid bacteria and Escherichia coli in the feces and the NH 3 and H 2 S concentration; 3 pigs were randomly selected from each replicate for blood collection, and the biochemical and immune indices in the serum were measured.

[0070] 1. Impact on the growth performance of growing pigs

[0071] The results of average daily weight gain, average daily feed intake and feed-to-weight ratio are shown in Table 7.

[0072] Table 7 Growth performance of growing pigs

[0073]

[0074] Note: The same lowercase letters in the same row indicate no significant difference (P>0.05), while different lowercase letters indicate significant difference (P<0.05). The data in the table are mean ± standard deviation; the same as in the following table.

[0075] As shown in Table 7, compared with the control group, the average daily weight gain of the pigs in the test group 1 increased significantly by 7.10% (P<0.05), and the feed-to-weight ratio decreased significantly by 4.85% (P<0.05); compared with the test group 2, the average daily weight gain of the pigs in the test group 1 increased significantly by 5.40% (P<0.05), and the feed-to-weight ratio decreased by 2.30% (P<0.05); there was no significant difference between the test group 2 and the control group (P>0.05). It can be seen from the results that adding feed fermented with Lactobacillus curvatus SQ13 to pig feed can better improve the growth performance of pigs, with high feed utilization rate and good economic value.

[0076] 2. Impact on fecal microbial count and odor

[0077] The number of viable lactic acid bacteria and Escherichia coli in feces and NH 3 and H 2 The results of S concentration are shown in Table 8.

[0078] Table 8 Microbial count and odor concentration in growing pig feces

[0079]

[0080] As shown in Table 8, compared with the control group, the number of lactic acid bacteria in the feces of growing pigs in the experimental group 1 increased by 122.58% (P<0.05), the number of Escherichia coli decreased by 71.03% (P<0.05), and the number of NH 3 and H 2 The concentration of S decreased by 57.14% (P<0.05) and 28.57% (P<0.05) respectively; compared with the control group, the number of lactic acid bacteria in the feces of growing pigs in the two experimental groups increased by 65.16% (P<0.05), the number of Escherichia coli decreased by 55.45% (P<0.05), and the number of NH 3 and H 2 There was no significant difference in S concentration; compared with group 2, group 1 had a higher concentration of NH 3 and H 2 The concentration of S decreased by 53.85% (P<0.05) and 23.08% (P<0.05) respectively. The results showed that adding a certain proportion of Lactobacillus curvatus SQ13 preparation to the feed of growing pigs can significantly increase the number of lactic acid bacteria in the feces of growing pigs, significantly reduce the number of Escherichia coli and NH 3 and H 2 S concentration, thereby improving the intestinal microecological environment of growing pigs and reducing the emission of harmful bacteria and odor in the breeding environment. In addition, compared with feed fermented with Lactobacillus curvatus SQ13, feed fermented with Lactobacillus curvatus SQ18 has a certain effect on improving intestinal flora, but cannot significantly reduce NH in feces. 3 and H 2 The results show that the fermented feed of Lactobacillus curvatus SQ13 has a significant function of reducing odor and can be used to prepare deodorant for animal breeding.

[0081] 3. Effects on serum parameters of growing pigs

[0082] The results of biochemical and immune parameters in serum are shown in Table 9.

[0083] Table 9 Serum biochemical and immune parameters of growing pigs

[0084]

[0085]

[0086] As shown in Table 9, compared with the control group, the serum TP content of growing pigs in the experimental group 1 increased by 3.12% (P<0.05), the ALT activity decreased by 27.54% (P<0.05), the UN content decreased by 4.20% (P<0.05), the TG content decreased by 10.87% (P<0.05), the IgG content increased by 7.83% (P<0.05), the IgM content increased by 40.28% (P<0.05), and the IgA content increased by 22.43% (P<0.05); the serum ALT activity of the experimental group 2 decreased by 18.79% (P<0.05), and the IgG content increased by 5.02% (P<0.05). There were no significant differences in the ALB, GLB, TC, GLU, HDL, LDL content and the AST, SOD, MDA, GSH-Px, T-AOC activities among the groups (P>0.05). Serum total protein can reflect the liver's ability to synthesize protein; alanine aminotransferase is one of the two indicators that reflect liver function. The increase in its activity indicates that liver cells may be damaged. Urea nitrogen concentration reflects the animal's utilization of protein and amino acids to a certain extent. When the amino acid balance is good, the serum urea nitrogen level is low. Triglycerides are an important indicator for measuring fat metabolism in the body. Immunoglobulins (mainly including IgG, IgM and IgA) are the main antibodies of humoral immunity, and their content can reflect the body's immune level to a certain extent. It can be seen from the results that compared with the control group diet and the Lactobacillus curvatus SQ18 preparation, adding a certain proportion of Lactobacillus curvatus SQ13 preparation to the growing pig feed can better improve the body's resistance and promote animal health.

Claims

1. Latilactobacillus curvatus SQ13, whose deposit number is: CGMCC No.31018.

2. A feed additive containing the Lactobacillus curvatus according to claim 1.

3. A feed additive according to claim 2, which is a fermented feed additive.

4. A feed containing the Lactobacillus curvatus according to claim 1 or the feed additive according to claim 2 or 3.

5. The feed according to claim 4, characterized in that The feed is fermented feed.

6. Use of the Lactobacillus curvatus according to claim 1, the feed additive according to claim 2 or 3, or the feed according to claim 4 or 5 in improving animal production performance and / or reducing odor emission.

7. The use according to claim 6, characterized in that The improving of animal production performance is to increase the daily weight gain of pigs, and the reducing of odor emission is to reduce NH3 and H2S in feces.

8. The use according to claim 7, characterized in that The amount of feed additives added is 0.25-1% of the daily diet.

9. Use of the Lactobacillus curvatus described in claim 1 in preparing an animal breeding deodorant.

10. A feed for reducing odor in animal breeding, characterized in that: It contains the Lactobacillus curvatus described in claim 1.

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