The Separation And Identification Of A Strains Bacillus Subtilis From Intestinal Of Laying Hens And Probiotic Application Effect To The Chicken

Our country is a big breeding animal husbandry country, livestock bacterial diseases are basically treated with antibiotics in the breeding process, with extensive use of antibiotics, a series of problems arises: Antibiotics can solve and kill pathogens, but also to produce pathogenic microorganisms resistant to antibiotics, according to the Ministry of Agriculture reported that, at present, many antibiotic drug exist resistance phenomenon, the formation of resistant strains of pathogens has become a global discussion problem and problems too difficult to solve, not only to reduce the efficacy of antibiotic, increase dose of drug, increase the relapse rate of the disease, extend the treatment cycle, but also cause complicationus of the disease, leading to animals mortality increased. Looking for an alternative to antibiotics has become a more pressing issue, which probiotics was first pushed to the forefront, then,whether probiotics can achieve expected effect? Therefore, the author made relevant experiments carried out to test for broiler and layer production performance indicators of fecal excretion and intestinal bacteria after use aspects separation and identification of significant differences analyzed.This experiment carried on the layers of intestinal bacteria separation, staining microscopy, biochemical test, the 16 s rRNA sequencing and do sequence homology analysis by NCBI Blast retrieval system, then with the bacillus subtilis 16 s rRNA sequence obtained from GenBank database do multiple sequence matching,then adjacency method was used to construct phylogenetic trees. The experiments also measured poultry feed conversion ratio,laying hens egg, egg weight, the antibody titer and manure index of crude protein, ash,calcium, phosphorus and other indicators by kay type nitrogen determination method,potassium permanganate method and so on.The experimental results showed that:Beneficial bacteria strains by laying hens intestinal separation, after 16 s rRNA gene sequences of sequencing and bacillus subtilis D53 strain homology more than 99%, Show that bacteria can exist in chicken intestines and separation, can maintain the role of the intestinal flora balance and other benefit to chicken;Probiotic on the chicken, after using probiotics can reduce the feed conversion ratio ofchicken, can keep the balance of intestinal flora, increase the absorption of protein, calcium,phosphorus in feed and reduce the emissions of nutrients, reduce the production cost, improve the economic benefits of farming;Laying hens test results that egg weight of experimental group 2 and group 3 with significant difference compared with control group(P < 0.05) after using of probiotic, the experimental groups each eggs bigger 0.96-2.5 g than the control group;In the aspect of time(broken, soft) egg rate,experiment 2 and group 3 significant difference compared with control group(P < 0.05), experimental group is lower than the control group by 23.9%- 28.4%; In the aspect of feed-egg ratio, experiment 1 and group 3 significant difference compared with control group(P < 0.05), the experimental group is lower than the control group by 4.65%,the shell thickness and egg length-width ratio difference was not significant;Manure index testing results show that the test group of ash content, Ca and the control group exist significant difference(P < 0.05), the experimental group ash percentage was 4.4% higher than the control group; the percentage of the experimental group calcium content is less than the control group,lower 1% than the control group; the phosphorus content of no significant difference(P >0.05),Statistically, the percentage of experimental group is less than the control group; the test antibody titer including the H5,H9,ND higher than control group;Experimental group on the number of lymphocyte and the control group significant difference(P < 0.05), the total number of white blood cells, intermediate cells and granulocyte count no significant difference with control group, but the experimental group bigger than the control group on numerical number. From the above test results show that the laying hens after using probiotics can increase egg quality and quality, reduce feed egg ratio, reduce the time(broken, soft) egg rate, increase absorption of feed, improve the disease resistance of the chicken body and the immune protection.