Identification And Analysis Of Drug Resistance Of Avian Escherichia Coli Isolated From Zhangqiu Area

Pathogenic Escherichia coli(E.coli)is one of the pathogens which would make the most serious harm to aquaculture,with a wide variety of serotype and extensive distribution.In recent decades,a large number of antibacterial drugs have been used for intensive production to prevent and treat disease and promote growth.Then,resistant strains of E.coli showed continuously increase,resistance spectrum to expand,for the reason of a long,widely and unreasonable use of the antibacterial drugs,it makes the antibiotic resistance mechanisms more complex and some of the strains are resistant to the new antibacterial drugs which have been not in clinical use.Detection and identification of epidemiology for the resistance gene of E.coli and illustrate the resistant phenotype and genotype is helpful to learn more about the occurrence and development of E.coli resistance and to optimize the reasonable application of antibiotics and to instruct clinical medication.Our study focused on the following aspects:Isolation and identification of E.coli and epidemic detection of drug resistance genes of different types of drug.In order to understand the popularity of avian pathogenic E.coli and the distribution of drug resistance genes of different antibiotic in Zhangqiu,Jinan,samples from infected poultry was collected followed by bacterial isolation and purification.Clinical bacteria were identified by bacterial culture characteristic test and biochemical test.Paper disc method was used for drug sensitive test,results indicated 7 strains of E.Coli showed drug resistance to alsomst all the antibiotics tested in this study including cephalosporins,tobramycin,ofloxacin,gentamicin,streptomycin,amikacin,kanamycin,piperacillin and ampicillin.Furthermore,general multiresistant could be observed to ?-lactam penicillins and cephalosporins.The isolates of 7 strains of Escherichia coli generally carry-lactam resistance and aminoglycoside resistance genes.The positive rates of TEM,CTX-M-1,ant(3")-Ia and OXA-2 genes were 100%,100%,42.86%and 42.86%,respectively.In this study,6 strains of Escherichia coli carry three kinds of drug resistance genes,one carries two kinds of resistance genes.The avian Escherichia coli carrying the lactam resistance gene has been widely prevalent in Zhangqiu area,and TEM and CTX-M-1 are the dominant genotypes,the detection rate of this resistant gene is 100%.The result of antibiotic resistance test of E.coli was consistent with the results of drug susceptibility test,which explained the extremely broad drug resistance spectrum of 7 strains of Escherichia coli isolated in Zhangqiu area at the molecular level,so as to provide effective control for Escherichia coli infection scientific basis.