Study On The Adhesion Of Lactobacillus To Broiler Intestinal Mucus

Oxford cup test was used in this study to determine the antibacterial effect of 5 Lactobacillus (Lactobacillus zeae, Lactobacillus agilis, Lactobacillus gasseri, Lactobacillus graminis and Lactobacillus acidophilis) on Escherichia coli. The size of the inhibitory zone was between 16.20 mm～23.70 mm. The best antibacterial effect was observed from Lactobacillus gasser with the largest inhibitory zone was 23.70 mm.γ-32P-ATP Adenosine triphosphate ([γ-32P]ATP) was used to label bacteria and to determine the adhesion rate of five Lactobacillus and one Escherichia coli. to immobilized mucus of duodenum, jejunum, ileum, cecum and colon of broiler in vitro. All tested strains were found to adhere in different gut compartments in different values. The adhesion values of five Lactobacillus were significantly higher (p<0.05) than Escherichia coli. The most adhesive strain was Lactobacillus gasseri (14.34%～25.95%) while the least adhesive strain was E.coli(3.18%～3.80%).To study the adhesion mechanism of Lactobacillus and Escherichia coli, Lactobacillus were pretreated with Trypsin or Sodium iodate before the adhesion experiment. Both Trypsin and Sodium iodatet treatment reduced (p<0.05) the level of adhesion of Lactobacillus whereas only Sodium iodate treatment reduced (p<0.05) the adhesion of Escherichia coli. The results indicated that carbohydrate and glycoprotein on the surface of Lactobacillus joined in the adhesion process and adhesion in the surface of Escherichia coli might have the characterization of glycoprotein. Mucoprotein treated by trypsin did not affect the adhesion of Lactobacillus and Escherichia coli, reduced significantly (p<0.05) the adhesion of Escherichia coli when treated by Sodium iodate. Results showed that adhesion receptors of Lactobacillus were not sensitive to both Trypsin and Sodium iodate, and the adhesion receptors of Escherichia coli had carbohydrate structure, which might be glycoprotein. The bacteria and mucoprotein were treated by heat to determine the adhesion rate of Lactobacillus and Escherichia coli. The result showed that the adhesion rate of Lactobacillus was reduced when the Lactobacillus were treated by 100℃for 10min (p>0.05), but the adhesion rate of Lactobacillus and Escherichia coli were both reduced significantly when they were treated by 65℃for 30min (p<0.05); the adhesion rate of Lactobacillus were reduced whereas the adhesion rate of Escherichia coli were increased.At the same time, the inhibition ability of two canine originated Lactobacillus on E.coli were determined by rejection, competition and replacement. The results showed that the five Lactobacillus and E.coli added in the mucus glycoprotein in certain order, compared with the control, the adhesion of E.coli was reduced significantly (p<0.05) by the rejection, competition and replacement, but there were no difference on the adhesion of Lactobacillus.