| The study was finished by two kind of probiotics selected from chicken, its aim is to detected the effect of adhesion in E.coli O78 in the digestive of chicken and properties of probiotics in vitro.In these experiments,the bearing capacity of acid and bile salt of probiotics were firstly detect by it's survival rate under the different pH values and bile concentration in MRS medium. Secondly, adhesion capacity of chicken intestinal epithelial cells was detected with probiotics through Gram stain, the adhesion inhibiting capacity of enteropathogenic E.coli in intestinal epithelial cells with probiotics was detected by indirect immunofluorescence method in vitro. Then the vivo study of chickens was made according to the results in vitro.Sensitive antibiotics was Selected cefoperazonly with intestinal flora of chicks by susceptibility test methods, to set up dysbacteriosis model induced by antibiotics, The effects of adhesion ability of probiotics on avian enteropathogenic E.coli O78 in the chicken digestive tract were tested, 1d 150 uninfected chicks were randomly divided into 6 groups of, treatment groups as follows:Group 1:Cefoperazone were drenched with Concentration of 40mg/kg/d succession for three days in order to cleansing intestinal bacteria, taking orally 0.5ml with 2×10~9cfu/ml concentration avian enteropathogenic E.coli O78 in fourth day.Group 2: Remove intestinal bacteria same with group 1, taking orally 0.5ml with 2×10~9cfu/ml concentration avian enteropathogenic E.coli O78 and simultaneous inoculation mixed liquid by equidensity of Lactobacillus acidophilus and Lactobacillus casei in fourth day.Group 3: Terile iso-osmia salines was drenched 0.5ml succession for three days and take orally 0.5ml with 2×10~9cfu/ml concentration of avian enteropathogenic E.coli O78.Group 4: Drenching succession same with group 3 for three days, then taking orally same with group 2 in fourth day.Group 5: The blank control of group1 and group 2.Group 6: The blank control of group3 and group 4.O78 on the enteron mucosa in craw, stomachus glandularis, duodenum, jejunum, ileum, caecum and rectum was identified and demeshed by the method of Gram stain, biochemical identification, and indirect immunofluorescence cultivation .and the effect of avian enteropathogenic E.coli in the chicken digestive tract determined by probiotics was analysed using statistical method of SPSS 16.0 .The test property of probiotics showed that two probiotics had a strong tolerance under different pH values and salt concentrations, and the tolerance of Lactobacillus acidophilus was better than Lactobacillus casei. In the experiment of adhesion ability in chick intestinal epithelial cells, both probiotics could adhere to epithelial cells, the number of Lactobacillus casei was higher than eosinophilic Lactobacillus'. The restrain of O78 adhesion by indirect immunofluorescence staining method results showed that the number of avian enteropathogenic E.coli reduced adhesion on epithelial cells compared with the control group, and the inhibiting on O78 by mixtured probiotics influences was most obvious, this is the same results with punch method in bacteriostasis trait.In vivo results showed, probiotics inhibited significantly the Avian enteropathogenic E.coli in the digestive tract colonization(P<0.05). Compared with both inhibited model of antibiotic group and group3, permanent planting bacterium of O78 of group 3 was significantly lower than antibiotic group. So infered that exogenous probiotic had the inhibition on the growth and reproduction of pathogenic, meanwhile promoting the growth of beneficial microorganisms in vivo, and conclude the probiotic enhancing the permanent planting of beneficia bacterium and preventing pathogenic microorganisms adhesion in digestive tract.
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