Prevalence and molecular characterization of verotoxin-producing Escherichia coli O۱۵۷:H۷ in cattle and sheep in Shiraz-Iran

Shiga toxin producing Escherichia coli have been associated with HUS, HC and TTP in human. We found recto-anal mucosal sample in sheep as well in cattle is the main site for E. coli O۱۵۷ localization. ۱۲۴۶ E. coli isolates from ۸۷۲ both healthy and diarrheic animals were analyzed, by screening for the presence of Shiga toxin-producing (VT ۱ and VT ۲) and intimin (eae) genes used Multiplex PCR. ۸۷(۹.۷۵%) VTEC from ۵۲ cattle and ۲۸(۷.۹۰%) from ۲۸ sheep were isolated. VT۲ gene was found to be more frequent than VT۱ in cattle (۵۴.۰۲% vs ۲۶.۴۳%), in contrast the same genes in sheep (۲۱.۴۲%vs۲۵%). There was observed significant difference in the origin of VT positive sheep in close contact with farms of cattle origin. Having cattle and sheep with each other was a possible risk factor. The animal was kept in pen was more localized than tethered. Young cattle were documented strongly significant high prevalence rate in E. coli O۱۵۷:H۷ than older, but no effect of age was observed on the occurrence of E. coli O۱۵۷ in sheep. Both diarrheic and healthy animals were shed E. coli O۱۵۷:H۷ in their feces. Sheep and dairy cow were not illustrated any significance differences geographical region and seasonal variation with E. coli O۱۵۷:H۷ prevalence rate.

کلیدواژه ها:

E. coli O۱۵۷ ، Cattle ، Sheep ، Iran