Lactobacillus acidophilus LAHuBR15 and application thereof
By providing Lactobacillus acidophilus LAHuBR15, the problems of low survival rate and insignificant antibacterial effect of Lactobacillus acidophilus in the digestive tract environment of livestock and poultry have been solved, resulting in a significant improvement in the health and production performance of livestock and poultry.
Patent Information
- Application Number
- CN202511489658.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-17
- Publication Date
- 2025-12-05
AI Technical Summary
Existing strains of Lactobacillus acidophilus have low survival rates in the digestive tract environment of livestock and poultry, making it difficult to effectively inhibit pathogens in livestock and poultry, and their effect on improving livestock and poultry production performance is not significant, resulting in unstable probiotic effects.
We offer Lactobacillus acidophilus LAHuBR15, which has broad-spectrum antibacterial activity, high temperature resistance, gastric acid resistance, bile salt resistance, and digestive enzyme resistance. It is used to prepare fermentation agents and feeds for livestock and poultry farming to improve health and production performance.
It significantly reduces the risk of pathogen infection in livestock and poultry, increases egg production in laying hens, reduces the feed conversion ratio, improves the chick survival rate, and promotes the health of livestock and poultry and the efficiency of breeding.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of microbial technology, specifically to Lactobacillus acidophilus LAHuBR15 and its applications. Background Technology
[0002] In livestock and poultry farming, diseases caused by bacterial pathogens such as Salmonella, Escherichia coli, and Staphylococcus aureus are a significant factor leading to economic losses. While traditional antibiotic prevention and treatment methods are effective, long-term use can easily lead to increased bacterial resistance, drug residues, and disruption of the intestinal microecological balance in animals, posing threats to food safety and public health. Therefore, developing safe, effective, and residue-free antibiotic alternatives, especially probiotic microbial preparations, has become a key research focus and an urgent industry need.
[0003] Lactobacillus acidophilus ( Lactobacillus agilis As an important type of probiotic, *Lactobacillus acidophilus* has attracted widespread attention due to its potential in regulating intestinal flora, enhancing immunity, and inhibiting pathogens. However, not all *Lactobacillus acidophilus* strains possess ideal probiotic properties. In practical applications, probiotic strains used in livestock and poultry need to possess several key characteristics: First, they must be able to survive and colonize effectively in the complex digestive environment of livestock and poultry (such as low-pH gastric juice, high concentrations of bile salts, and the action of digestive enzymes); second, they need to have a significant inhibitory ability against common livestock and poultry pathogens; and finally, ideal probiotics should also have a positive impact on the host's production performance (such as egg production rate, feed conversion efficiency, and hatching quality of fertilized eggs in laying hens).
[0004] Currently, there is a lack of systematic evaluation or insignificant efficacy of *Lactobacillus acidophilus* strains against specific livestock and poultry pathogens (such as *Haemophilus paragallinarum*, *Salmonella fowleri*, and *Actinobacillus pleuropneumoniae*). More importantly, there are relatively few reports on *Lactobacillus acidophilus* strains and their application technologies that can be clearly demonstrated to significantly promote key production performance indicators of laying hens (such as continuously increasing egg production rate, significantly reducing feed conversion ratio, and improving chick survival rate). Although some *Lactobacillus acidophilus* strains have been studied or applied, challenges remain in practical promotion. The survival rate of many strains in harsh digestive tract environments (such as low pH and high bile salts) is not ideal, resulting in insufficient number of live bacteria reaching the intestines and exerting their effects after oral administration, affecting the stability of the probiotic effect. Therefore, isolating and screening novel *Lactobacillus acidophilus* strains that possess both highly efficient antibacterial activity and can effectively improve the health and production performance of livestock and poultry is of great significance for promoting green and healthy farming. Summary of the Invention
[0005] The present application aims at overcoming the deficiencies of the prior art, and provides lactobacillus acidophilus LAHuBR15 and application thereof. The lactobacillus acidophilus LAHuBR15 of the present application has the ability of inhibiting a plurality of pathogenic bacteria of livestock and poultry in vitro, and has excellent anti-adverse characteristics such as high temperature resistance, gastric acid resistance, bile salt resistance and digestive enzyme resistance.
[0006] To achieve the above-mentioned purpose, the technical scheme designed by the present application is as follows: The present application provides lactobacillus acidophilus LAHuBR15. Lactobacillus agilis The preservation number of the lactobacillus acidophilus LAHuBR15 is CCTCC NO: M 20241050.
[0007] The present application also provides application of the lactobacillus acidophilus LAHuBR15 in bacteriostasis.
[0008] Further, the bacteriostatic strain is chicken salmonella, mouse typhoid salmonella, paracolon hemophilus, porcine pleuropneumonia actinobacillus, klebsiella pneumoniae, staphylococcus aureus, escherichia coli, porcine pasteurella and duck epidemic rimer's bacillus. The present application also provides lactobacillus acidophilus fermentation agent, which comprises the lactobacillus acidophilus LAHuBR15. 8 ~6×10 8 CFU / mL.
[0009] The present application also provides a preparation method of the fermentation agent, comprising the following steps: (1) freeze-dried lactobacillus acidophilus LAHUBR15 is recovered on an MRS plate, and is continuously subcultured for 3 times; (2) single colonies of the lactobacillus acidophilus LAHUBR15 are picked in MRS broth, and are cultured at 37 DEG C in an anaerobic incubator for 12-16 h, so that the lactobacillus acidophilus fermentation agent is obtained.
[0010] The present application also provides application of the fermentation agent in preparation of a product for preventing chicken infection with chicken salmonella.
[0011] The present application also provides application of the lactobacillus acidophilus LAHuBR15 in preparation of feed.
[0012] The present application also provides feed, which comprises base feed and the lactobacillus acidophilus LAHUBR15. 8 ~6×10 8 CFU / kg.
[0013] The application also provides application of the feed in improving production performance of laying hens, wherein the production performance comprises improving egg production and average egg weight of the laying hens and reducing feed-egg ratio of the laying hens.
[0014] The application also provides application of the feed in improving healthy chick rate of laying hens.
[0015] The application has the following beneficial effects: The lactobacillus acidophilus LAHuBR15 provided by the application has broad-spectrum bacteriostatic activity, can effectively inhibit a plurality of common livestock and poultry pathogenic bacteria (such as salmonella) in vitro, and is helpful to reduce the risk of livestock and poultry infection. The strain has excellent high-temperature resistance, gastric acid resistance, bile salt resistance and digestive enzyme resistance and other stress resistance characteristics, which ensures its high survival rate and stability in feed processing and livestock and poultry digestive tract. Application of the strain in livestock and poultry breeding can significantly reduce the tissue bacterial load after pathogenic bacteria infection, thereby improving the health level of livestock and poultry. Adding the strain in the feed of laying hens can significantly improve the egg production rate, reduce the feed-egg ratio, and improve the breeding efficiency. Application of the strain can effectively improve the healthy chick rate and promote the health of livestock and poultry groups, and has good popularization and application prospect. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 Figure is a growth curve diagram of lactobacillus acidophilus LAHuBR15; Figure 2 Figure is a result diagram of tissue bacterial load of chicks after infection with salmonella; In the figure, A is the liver, B is the spleen, and C is the cecum. Figure 3 Figure is a result diagram of the effect of adding lactobacillus acidophilus LAHuBR15 on the egg production rate of laying hens; Figure 4 Figure is a result diagram of the effect of adding lactobacillus acidophilus LAHuBR15 on egg weight; Figure 5 Figure is a result diagram of the effect of adding lactobacillus acidophilus LAHuBR15 on feed-egg ratio; Figure 6 Figure is a result diagram of the effect of adding lactobacillus acidophilus LAHuBR15 on healthy chick rate. DETAILED DESCRIPTION
[0017] The application will be further described in detail below in combination with specific examples, so as to be understood by those skilled in the art.
[0018] Example 1 A lactobacillus acidophilus LAHuBR15 The example provides a lactobacillus acidophilus (Lactobacillus acidophilus) LAHuBR15. Lactobacillus agilis) LAHuBR15, which was preserved on May 23, 2024, and the preservation number is CCTCC NO: M 20241050, and the preservation unit is China Center for Type Culture Collection, and the preservation address is Wuhan University, Wuhan, China, and the postcode is 430072.
[0019] The growth curve of Lactobacillus acidophilus LAHuBR15 was determined. Lactobacillus acidophilus LAHuBR15 was inoculated in MRS broth in a clean bench, and was cultured anaerobically overnight (12-16 h). The next day, it was transferred to fresh MRS broth at a ratio of 2% (volume ratio) at 0 h, 2 h, 4 h, 6 h, 8 h, 10 h and 12 h, and 100 μL was taken to a cuvette at each time point, and the OD 600nm value of the bacterial solution was determined by a spectrophotometer.
[0020] In order to understand the growth trend and regularity of Lactobacillus acidophilus LAHuBR15, the OD 600nm absorbance value of the strain at different times was determined, and the growth curve was drawn. As shown in Figure 1 , Lactobacillus acidophilus LAHuBR15 grew well in the culture medium, and the highest OD 600nm absorbance value could reach 3.17. The strain LAHuBR15 was in the lag phase at 0-2 h, in the logarithmic growth phase at 2-6 h, and in the stationary phase at 6-12 h.
[0021] Example 2 Evaluation of the in vitro bacteriostatic effect of Lactobacillus acidophilus The agar punching method was used to detect the bacteriostatic effect of Lactobacillus acidophilus LAHuBR15 on pathogenic bacteria.
[0022] 1. Preparation of indicator bacteria: Take chicken salmonella (SS medium), mouse typhoid salmonella (SS medium), parahemophilus (TSA medium added with 10% inactivated bovine serum, 10 μg / mL NAD solution), actinobacillus pleuropneumoniae (TSA medium added with 10% inactivated bovine serum, 10 μg / mL NAD solution), klebsiella pneumoniae (LB medium), staphylococcus aureus (LB medium), escherichia coli (LB medium), pasteurella multocida (TSA medium added with 10% inactivated bovine serum) and rimerella anatipestifer (TSA medium added with 10% inactivated bovine serum, anaerobic culture) from the ultra-low temperature freezer, respectively, and activate them on the corresponding agar plates. After three generations, well-conditioned single colonies were inoculated in the corresponding liquid medium, and were cultured overnight at 37°C on a shaker at 180 r / min. The concentration was adjusted to 10 8 CFU / mL; 2. Preparation of probiotic bacteria broth: pick Lactobacillus acidophilus LAHUBR15 single colony into MRS broth, anaerobic incubation, 180 r / min overnight, standby, the concentration of Lactobacillus acidophilus LAHUBR15 is 5×10 8 6×10 8 CFU / mL; 3. Bacterial coating, punching, liquid adding: take 100 μL indicator bacteria to the corresponding agar plate with a pipette, immerse a sterile cotton swab in the indicator bacteria broth and press off the excess indicator bacteria broth, then evenly smear the indicator bacteria on the agar plate with the cotton swab. Punch holes on the agar plate with a puncher, the distance between the holes is at least 2 cm, and the agar in the holes is picked off with a needle tip. Add 50 μL of the prepared probiotic bacteria broth to the sample hole with a pipette, and MRS medium as a blank control, with 3 repeats for each sample hole; 4. Measurement of inhibition zone: place all the plates in the incubator, incubate at 37℃ for 24 h, and then measure the diameter (mm) of the inhibition zone.
[0023] Table 1 In vitro antibacterial effect of Lactobacillus acidophilus The results are shown in Table 1. Lactobacillus acidophilus LAHUBR15 has inhibitory effect on chicken Salmonella, mouse typhoid Salmonella, avian Pasteurella multocida, porcine actinobacillus pleuropneumoniae, Klebsiella pneumoniae, Staphylococcus aureus, Escherichia coli, swine Pasteurella and duck Riemerella anatipestifer.
[0024] Example 3 Lactobacillus acidophilus resistance detection 1. High temperature resistance experiment (1) Transfer the Lactobacillus acidophilus LAHUBR15 overnight culture in Example 2 into MRS broth at a volume ratio of 1:10, take 100 μL of the bacterial solution into physiological saline for 10 -1 , 10 -2 , 10 -3 , 10 -4 , 10 -5 times dilution, and perform plate coating and counting for the bacterial solution with different dilutions. Then put the transferred bacterial solution into a 50℃ water bath for 20 min.
[0025] (2) Dilute, plate coat and count according to the same steps as step (1). Finally, count the colonies and calculate the survival rate: strain survival rate = number of viable bacteria after 20 min of different treatments / number of viable bacteria at the beginning of different treatments × 100%. The results are shown in Table 2.
[0026] 2. Acid resistance test (1) The pH value of MRS broth was adjusted to 3.5 using 20% hydrochloric acid, and then sterilized in a high-pressure steam sterilization pot at 121.5°C for 15 min. The overnight cultured Lactobacillus acidophilus LAHUBR15 was transferred into the culture medium with a volume ratio of 1:10, and 100 μL of the bacterial solution was diluted in physiological saline by 10 -1 , 10 -2 , 10 -3 , 10 -4 , 10 -5 times, and the bacterial solution with different dilutions was plated and counted.
[0027] (2) Then the transferred bacterial solution was placed in an incubator for 3 h of incubation, and then the same steps of dilution, plating, and counting were performed. Finally, the colony count was performed and the survival rate was calculated, and the strain survival rate = the number of viable bacteria after different treatments for 3 h / the number of viable bacteria at the beginning of different treatments x 100%. The results are shown in Table 2.
[0028] 3. Cholate salt tolerance test (1) 0.1 g of No. 3 cholate salt was weighed on an electronic balance and dissolved in 100 mL of MRS broth, and the MRS broth was adjusted to a cholate salt concentration of 0.1%, and then sterilized in a high-pressure steam sterilization pot at 121.5°C for 15 min. The overnight cultured Lactobacillus acidophilus LAHUBR15 was transferred into the prepared culture medium with a volume ratio of 1:10, and 100 μL of the bacterial solution was diluted in physiological saline by 10 -1 , 10 -2 , 10 -3 , 10 -4 , 10 -5 times, and the bacterial solution with different dilutions was plated and counted.
[0029] (2) Then the transferred bacterial solution was placed in an incubator for 3 h of incubation, and then the same steps of dilution, plating, and counting were performed. Finally, the colony count was performed and the survival rate was calculated, and the strain survival rate = the number of viable bacteria after different treatments for 3 h / the number of viable bacteria at the beginning of different treatments x 100%. The results are shown in Table 2.
[0030] 4. Artificial gastric juice and artificial intestinal juice test (1) Preparation of artificial gastric juice and artificial intestinal juice ① Artificial gastric juice formula: adjust the pH of sterile water to 3.0 with dilute hydrochloric acid, add pepsin (Shanghai Yuan Ye Biological Technology Co., Ltd.) at a solid-liquid ratio of 1:100 g / mL, filter sterilize with a 0.22 μm pore size microfiltration membrane, and prepare for use.
[0031] ② Artificial intestinal fluid formulation: Weigh 6.8 g of potassium dihydrogen phosphate and dissolve it in 500 ml of sterile water to obtain a potassium dihydrogen phosphate solution. Adjust the pH of the potassium dihydrogen phosphate solution to 6.8 with 0.1 mol / L NaOH solution, and bring the volume to 1000 mL. Add trypsin (Shanghai Yuanye Biotechnology Co., Ltd.) at a solid-liquid ratio of 1:100 g / mL. Filter the solution through a 0.22 μm microporous membrane for sterilization and set aside.
[0032] (2) The overnight cultured Lactobacillus acidophilus LAHUBR15 was transferred to pre-prepared artificial gastric fluid and artificial intestinal fluid at a volume ratio of 1:10. 100 μL of the mixed solution was then serially diluted in physiological saline (10 μL / mL). -1 10 -2 10 -3 10 -4 10 -5 Different dilutions of bacterial solutions were plate-coated for counting.
[0033] (3) Then, place the transferred bacterial culture into an incubator and incubate for 3 hours. Next, follow the same steps as the previous step to dilute, plate, and count the bacteria. Finally, count the colonies and calculate the survival rate. The survival rate of the strain is calculated as: (Number of viable bacteria after 3 hours of different treatments / Number of viable bacteria at the beginning of different treatments) × 100%.
[0034] The experimental results are shown in Table 2. The high-temperature resistance results showed that the survival rate of *Lactobacillus acidophilus* LAHUBR15 was 67.6% at 50℃. The acid resistance results showed that the survival rate of *Lactobacillus acidophilus* LAHUBR15 was 89.4% at pH 3.5. The bile salt resistance results showed that the survival rate of *Lactobacillus acidophilus* LAHUBR15 was 81.8% at a bile salt concentration of 0.1%. The resistance results to artificial gastric and intestinal fluids showed that the survival rate of *Lactobacillus acidophilus* LAHUBR15 was 65.0% in artificial gastric fluid and 96.6% in artificial intestinal fluid.
[0035] Table 2 Stress resistance of Lactobacillus acidophilus Example 4 Preparation of Lactobacillus acidophilus fermentation inoculum 1. Take the lyophilized Lactobacillus acidophilus LAHUBR15 from the -80℃ freezer, use an inoculation loop to take Lactobacillus acidophilus LAHUBR15 on an MRS plate for revival, and passage it three times to ensure the viability of the probiotics.
[0036] 2. Select a single colony of Lactobacillus acidophilus LAHUBR15 and incubate it anaerobically at 37℃ for 12 hours to obtain the Lactobacillus acidophilus fermentation agent, in which the concentration of Lactobacillus acidophilus LAHUBR15 is 5×10⁻⁶.8 6 x 10 8 CFU / mL.
[0037] Example 5 Detection of Lactobacillus acidophilus on the tissue load of Salmonella in infected chickens 1. 70 one-day-old white leihang chickens were randomly divided into four groups, the first group was the blank group (NC), the second group was the infection group (PC), and the third group was the Lactobacillus acidophilus group (LAC). There were 10 chickens in the blank group, and 30 chickens in each of the infection group and the Lactobacillus acidophilus group.
[0038] 2. Each group was treated as follows: At one day old, the white leihang chickens were gavaged with the Lactobacillus acidophilus fermentation inoculum of Example 4, and the Lactobacillus acidophilus group was gavaged with a dose of 1 x 10 8 CFU of Lactobacillus acidophilus per 1 mL, and the blank group and the infection group were gavaged with 1 mL of normal saline, until the end of the test. At 3 days old, the infection group (PC) and the Lactobacillus acidophilus group (LAC) were infected with chicken Salmonella by gavage using a gavage needle, and the infection dose was 2 x 10 9 CFU per 1 mL. The blank group was gavaged with the same volume of normal saline, and the chickens were fasted and deprived of water for 12 h before gavage.
[0039] 3. One day, 3 days, and 5 days after the white leihang chickens were infected with chicken Salmonella, 8 chickens were randomly selected from each group and sacrificed, and the liver, spleen, and cecum were taken after dissection, weighed, and then placed in 3-5 times the volume of normal saline. The tissues were ground into homogenate in a tissue grinder. 30 μL of tissue homogenate was taken from the cecum tissue for ten-fold gradient dilution to 10 -1 -10 -6 , and 10 μL of each dilution was taken for viable cell counting. 30 μL of tissue homogenate was taken from the liver and spleen tissue for ten-fold gradient dilution to 10 -1 -10 -4 , and 10 μL of each dilution was taken for viable cell counting. Then, after 12 h of incubation in a 37°C constant temperature incubator, the single colonies growing on the plates were counted.
[0040] The results are shown in Table 1. Figure 2 Compared with the infection group (PC), the spleen tissue load of the Lactobacillus acidophilus group (LAC) was significantly reduced (P < 0.001) one day after infection with chicken Salmonella, the cecum tissue load of the Lactobacillus acidophilus group (LAC) was significantly reduced (P < 0.0001), and there was no significant difference in the liver tissue load of the Lactobacillus acidophilus group (LAC). p <0.001), the cecum tissue load of the Lactobacillus acidophilus group (LAC) was significantly reduced (P < 0.0001), and there was no significant difference in the liver tissue load of the Lactobacillus acidophilus group (LAC). p <0.0001), the cecum tissue load of the Lactobacillus acidophilus group (LAC) was significantly reduced (P < 0.0001), and there was no significant difference in the liver tissue load of the Lactobacillus acidophilus group (LAC). p<0.001) ; on the 5th day after infection, the liver tissue bacterial load of the Lactobacillus acidophilus group was significantly lower than that of the infection group (PC) (P < 0.001) ; the spleen and cecal tissue bacterial loads (P < 0.0001) were also significantly reduced. The results show that the Lactobacillus acidophilus LAHUBR15 of the present application can effectively inhibit the colonization of chicken Salmonella in the liver, spleen and cecum. p <0.001), spleen and cecal tissue bacterial loads (P < 0.0001) were also significantly reduced. The results show that the Lactobacillus acidophilus LAHUBR15 of the present application can effectively inhibit the colonization of chicken Salmonella in the liver, spleen and cecum. p <0.0001), spleen and cecal tissue bacterial loads (P < 0.0001) were also significantly reduced. The results show that the Lactobacillus acidophilus LAHUBR15 of the present application can effectively inhibit the colonization of chicken Salmonella in the liver, spleen and cecum.
[0041] Example 6 Feed LAHUBR15 The present embodiment provides a feed LAHUBR15, which comprises a basic feed and Lactobacillus acidophilus LAHUBR15, and the added amount of Lactobacillus acidophilus LAHUBR15 in the feed LAHUBR15 is 5 x 10 8 ~6 x 10 8 CFU / kg.
[0042] Example 7 Effect of Lactobacillus acidophilus on the production performance of laying hens 1. 240 260-day-old Sugu laying hens were selected and divided into two groups: Lactobacillus acidophilus group (LAC) and control group (Con), with 3 replicates in each group, 40 chickens in each replicate, and the temperature, humidity and light of the chickens in each group were kept consistent.
[0043] 2. From the 8th day, the daily diet (antibiotic-free feed) of the Lactobacillus acidophilus group was replaced with the feed LAHUBR15 of Example 6 every day, and the control group was fed with antibiotic-free feed as the daily diet (i.e. the basic feed of Example 6) every day until the end of the test. All chickens were raised in cages and had free access to food and water every day. The environmental conditions of temperature, humidity and light were consistent with the environment of the farm.
[0044] 3. The effect of adding Lactobacillus acidophilus during feeding on the production performance of laying hens was evaluated by monitoring and collecting data on the egg production, average egg weight and feed to egg ratio of 240 Sugu laying hens within 28 days.
[0045] The results are shown in Table 1. Figure 3 As shown in Table 1, before replacing the daily diet, the average egg production rates of the control group (Con) and the Lactobacillus acidophilus group (LAC) were 84.48% and 84.90%, respectively, with no statistically significant difference. In the first week after replacing the daily diet, the egg production rates of the two groups were 84.17% and 87.8%, respectively, and the egg production rate of the Lactobacillus acidophilus group was higher than that of the control group, but the difference was not significant (p > 0.5). In the second and third weeks of continuous feeding after replacing the daily diet, the egg production rates of the Lactobacillus acidophilus group were 88.96% and 88.65%, respectively, which were significantly higher than the egg production rates of the control group, 83.96% and 84.48% (p < 0.05). It is shown that adding Lactobacillus acidophilus LAHUBR15 in the feed can improve the egg production rate of laying hens.
[0046] Results as shown in Figure 4 the average egg weight of the control group (Con) and Lactobacillus acidophilus group (LAC) were 55.92 g and 56.15 g, respectively, with no statistical difference (p>0.5). In the first week after changing the diet, the egg weight of the two groups was 56.03 g and 55.96 g, respectively, with no significant difference (p>0.5). In the second and third weeks of continuous feeding after changing the diet, the egg weight of the Lactobacillus acidophilus group was 57.24 g and 56.78 g, respectively, slightly higher than the egg rate of the control group 55.55 g and 56.49 g, with no significant difference (p>0.5).
[0047] Results as shown in Figure 5 the average feed-egg ratio of the control group (Con) and Lactobacillus acidophilus group (LAC) were 2.34 and 2.33, respectively, with no statistical difference. In the first week after changing the diet, the feed-egg ratio of the two groups was 2.38 and 2.37, respectively, and the feed-egg ratio of the Lactobacillus acidophilus group was lower than that of the control group, but the difference was not significant (p>0.5). In the second and third weeks of continuous feeding after changing the diet, the feed-egg ratio of the Lactobacillus acidophilus group was 2.3 and 2.23, respectively, significantly lower than the feed-egg ratio of the control group 2.38 and 2.32 (p<0.05). It is proved that adding Lactobacillus acidophilus LAHUBR15 in feed can reduce the feed-egg ratio of laying hens and improve the feed conversion rate.
[0048] 4、Lactobacillus acidophilus on the effect of healthy chick rate The above Suqin laying hens were fed to the 20th day and the 24th day, and artificial insemination was carried out twice, and 360 fertilized eggs were collected in each group, of which 120 were collected in each repeat, and hatching was carried out. After the birth of the chicks, the healthy chick rate was calculated. The judgment standard of healthy chicks is: chicks with bright down, good umbilical healing and strong vitality are healthy chicks, and the healthy chick rate = healthy chick number / hatch number x 100%.
[0049] Results as shown in Figure 6 The total number of hatched chicks in the control group was 327, of which 317 were healthy chicks, and the healthy chick rate was 96.94%; the total number of hatched chicks in the Lactobacillus acidophilus group was 330, of which 324 were healthy chicks, and the healthy chick rate was 98.18%. The healthy chick rate of the Lactobacillus acidophilus group was higher than that of the control group, but there was no significant difference (p>0.5). It is proved that adding Lactobacillus acidophilus LAHUBR15 in feed can improve the healthy chick rate of laying hens to a certain extent.
[0050] Other parts not described in detail are prior art. Although the above embodiment has made a detailed description of the present application, it is only a part of the embodiment of the present application, not all the embodiments, and people can also obtain other embodiments according to the present embodiment without creativity, which all belong to the protection scope of the present application.
Claims
1. Lactobacillus acidophilus LA HuBR 15, characterized in that: The Lactobacillus acidophilus (Lactobacillus acidophilus) Lactobacillus agilis The preservation number of LAHuBR15 is CCTCC NO: M 20241050.
2. Use of Lactobacillus acidophilus LAHuBR15 of claim 1 in bacteriostasis.
3. Use according to claim 2, characterized in that: The bacteriostatic strains are chicken salmonella, mouse typhoid salmonella, parahemophilus, porcine pleuropneumonia actinobacillus, klebsiella pneumoniae, staphylococcus aureus, escherichia coli, porcine pasteurella and duck epidemic rimer's bacillus.
4. A Lactobacillus acidophilus fermentation inoculant, characterized by: The fermentation agent comprises the Lactobacillus acidophilus LAHuBR15 according to claim 1, and the concentration of the Lactobacillus acidophilus LAHuBR15 in the fermentation agent is 5x10 8 6x10 8 CFU / mL.
5. A method of producing the fermentation inoculant of claim 4, characterized by: The method comprises the following steps: (1) freeze-dried Lactobacillus acidophilus LAHuBR15 is recovered on MRS plate and continuously subcultured for 3 times; (2) Lactobacillus acidophilus LAHuBR15 single colony is picked and cultured in MRS broth at 37 DEG C in an anaerobic incubator for 12-16 h, and Lactobacillus acidophilus fermentation inoculum is obtained.
6. Use of the fermentation inoculum of claim 4 in preparing a product for preventing chicken from being infected with chicken salmonella.
7. Use of Lactobacillus acidophilus LAHuBR15 of claim 1 in preparing feed.
8. A feed, characterized in that: The feed includes a basal feed and the Lactobacillus acidophilus LAHUBR15 according to claim 1, and the Lactobacillus acidophilus LAHUBR15 is added in an amount of 5 x 10 8 6 x 10 8 CFU / kg in the feed.
9. Use of the feed of claim 8 for improving the performance of laying hens. The production performance includes increasing egg laying rate and average egg weight of laying hens and reducing feed to egg ratio of laying hens.
10. Use of the feed of claim 8 in increasing healthy chick rate of laying hens.