Isolation and characterization of stx1 and stx2 toxin-producing Escherichia coli in neonatal lambs with diarrhea in Nineveh governorate, Iraq

Escherichia coli causes many health problems in lambs, the most prominent of which is diarrhea, the study aimed to detect the shiga toxins genes in E.coli isolated from the suckling lambs affected with diarrhea in Nineveh governorate. 91 fecal samples were collected from suckling lambs from different areas of Nineveh governorate during February 2022.Fecal sampling was performed directly from the rectum and placed in sterile containers, then transferred directly to the research unit of the veterinary medicine faculty at university of Mosul. Standard microbiological methods including culture in EMB, MacConkey and brilliance agars along with biochemical analyzes were performed. Molecular confirmations were done using specific primer sets targeting uidA gene for E.coli and Stx1 and Stx2  for shiga toxin respectively. The result of the present study showed that the prevalence rate of E.coli was 58.24%(53/91). Based on the PCR assay, the uidA, Stx1 and Stx2 were found in all the E.coli isolates 100% (53/53). It was concluded that the high isolation rate of E.coli from the lambs indicates lack of housing and hygienic procedures both for lactating ewes’ health and the environment.