Isolation,Identification and Related Pathogenicity Analysis of Duck Pathogenic E.coli

To analyze the pathogenicity and biological characteristics of duck E.coli,27 strains of duck pathogenic E.coli were isolated from dead ducks with the typical characterize of colibacillosis by isolation and culture,physical and chemical properties identification in Xichang city.O serotype identification,drug sensitivity test and virulence associated genes were detected in 27 strains of duck pathogenic E.coli.The result showed that the predominant serotypes were O119,O86,O126,O142 and O44,which accounted for 55.56%.O119 was the epidemic and pathogenic serotype in this farm,which accounted for 40.74%in 27 strains of duck pathogenic E.coli.Through the drug sensitivity test of 20 kinds of clinical commonly used drugs,we found that all strains were sensitive to amikacin,gentamicin and polymyxin B.Besides,10drugs(ceftriaxone,etc)were lightly sensitive.However,these strains were resistant to 5kinds of drugs(rifampicin,etc).The detection result of PCR about virulence associated genes indicated that the positive of iutA,hlyF,Iss,IroN,ompT,fyuA,irp2,Tsh and papA genes were 100.00%,fimCand K99 genes were59.26% and 7.40%,respectively.The results provided an important reference for effective prevention and control of duck colibacillosis,and laid the foundation for further study of E.coli.