Detection of eaeA, hlyA, stx1 and stx2 genes in pathogenic Escherichia coli isolated from broilers affected with colibacillosis

Foodborne outbreaks associated with shiga toxin-producing Escherichia coli (STEC) have been well documented worldwide. STECs are major causative agents of gastroenteritis in humans that may be complicated by hemorrhagic colitis (HC), hemolytic uremic syndrome (HUS), and thrombotic thrombocytopenia purpura (TTP).
The aim of this study was to investigate the presence of virulence-associated genes including eaeA, hlyA, stx1 and stx2 in Escherichia coli strains isolated from broiler’s Colibacillosis in the northeast of Iran.
From a total of 78 E.coli strains isolated from yolk sac infection, hepatitis and pericarditis, that were referred to educational veterinary clinic during 2011-2014, subculturing of the isolates was performed using selective media and a typical colony from each sample was subjected to multiplex PCR assay for identification of the presence of STEC important virulence-associated genes (eaeA, hlyA,stx1 and stx2) causing shiga toxin-mediated diseases.

Of 78 E.coli isolates, one isolate was positive for both eaeA and hlyA genes while negative for stx1 and stx2 genes.
The results showed low prevalence of STEC virulence genes associated with human infections in avian pathogenic E.coli (APEC) strains isolated from different flocks of broilers affected with colibacillosis.