Detection of inhibitor-resistant β-lactamase (IRBLs) and analysis of drug-resistance of avian pathogenic E. coli in duck.

Based on the drug-resistance characters of IRBLs,we studied the prevalence of IRBLs among 40 clinical isolates in duck E.coli was studied by K-B test and the drug-resistance of IRBLs-producer to antibacterial drugs was analyzed.The results showed that 4 isolates produced IRBLs,with resistance to amoxi-cillin,amoxicillin/clavulanic acid,ampicillin,ampicillin/sulbactam,ticarcillin/clavulanicacid,florfenicol,gentamycin,neomycin,sulfadiazine and doxycycline,which suggested that IRBLs-producing isolates had emerged in China,and were characterized by multidrug-resistance.Besides,two IRBLs-producing strains were susceptible to piperacillin/tazobactam,resulting from the protection of tazobactam to piperacillin.What's more,there was one IRBLs-producing strain which was resistant to the third generation cephalosporins,which explained it may also produced ESBLs or AmpC,and it implyed the further development trend about IRBLs.