畜禽及水环境大肠杆菌mcr-1基因的流行病学调查与耐药性分析OA北大核心CSTPCD

The purpose of the present study was to investigate the prevalence of mcr-1 gene in Escherichia coli from different sources,drug resistance of E.coli and drug resistance profile of mcr-1 positive E.coli to provide a reference for the control of mcr-1 prevalence and polymyxin resistance.The mcr-1 gene was screened by PCR for E.coli isolated from chickens,rabbits,pigs,slaughterhouses,urban sewage sources,rivers and wild fish.The carrying rates of 8 drug resistance genes was also screened in this study.E.coli strains from different sources were tested for their resistance to ampicillin,ciprofloxacin,fluorine benzene nicol,cefepime,nalidixic acid,tetracycline,ceftazidime,kanamycin,gentamycin,amikacin,streptomycin,amoxicillin,aztreonam and polymyxin to analyze the mcr-1 positive rate.A total of 326 E.coli samples were collected for testing mcr-1 gene,of which 45 were mcr-1 positive with an average carrying rate of 13.8%.The mcr-1 gene carrying rates of E.coli samples were 16.3%(16/98)in chickens,14.5%(8/55)in rabbits,8.9%(4/45)in pigs,10%(4/40)in slaughterhouses,26%(13/50)in urban sewages,and 0 in river and wild fish sources.E.coli was generally resistant to the tested antibiotics,among which the resistance rates to amoxicillin and ampicillin were generally high while the resistance rates to amikacin and polymyxin were relatively low.The carrying capacity of mcr-1 was consistent with polymyxin resistance.In general,the drug resistance ratio of other drugs was higher than the carrying rate of drug resistance genes,which was related to the multiple drug resistance mechanism of the same antibiotic.The mcr-1 positive E.coli had high multi-drug resistance.E.coli from livestock and poultry had high mcr-1 gene carrying rate and extensive drug resistance.Therefore,it is necessary to reduce the use of antibiotics and control the spread of drug resistance gene and drug resistance.