Surveillance of Susceptibility to Antibiotics of Escherichia coli from Chicken

37 strains of Escherichia coli were isolated from chickens that died of diseases in Shanxi Province.Surveillance on the antibiotic resistance of E.coli strains was conducted.Antibiotic resistance of 37 strains to 14 antimicrobial drugs was detected by disk diffusion susceptibility test.The results indicated that the isolates showed a greater or lesser degree resistance to all the antimicrobial drugs except for amikacin.Most isolates displayed a highest level resistance to phosphonomycin,followed by sulfamethazine,and most isolates showed cross-drug-resistance to quinolones.The minimum inhibited concentration(MIC) of six antimicrobial drugs against 37 isolates was detected by vitro microdilution method.The results showed that there were great differences among the MIC of the same antimicrobial drug to the isolates.The most of them was enorofloxacin.