This study aimed to evaluate prevalence, characteristics, genotypic diversity and antibacterial susceptibility of Escherichia coli encoding Shiga toxin 2f in domestic pigeons in different provinces of Iran. A total of 117 faecal samples were collected from pigeons and were subjected to molecular detection of stx2f. In total, 20, 258, 214 and 9% of pigeons from Tehran, Ferdows, Garmsar and Babol cities carried stx2f+ isolates, respectively. Of the 460 E. coli isolates examined, 43 were stx2f+ and most also carried eae (953%) and astA (977%) genes. Some of the stx2f+ isolates harboured cnf (93%), but all were negative for stx1, stx2 (other subtypes) and ehly. Most Strains (90%) were assigned to B1 phylogroup and possessed Intimin-b. Fingerprinting of the stx2f+ isolates using either enterobacterial repetitive intergenic consensus sequences (ERIC) or random amplified polymorphic DNA (RAPD) – polymerase chain reaction revealed seven distinct profiles by each method, with one prevailing (651 and 465%, respectively). By the combination of methods, 10 profiles were recognized. Ten isolates from different profiles were shown to belong to O20, O78 and O115 serogroups, and eight were 100% identical in the stx2f gene sequence. The strains were consistently resistant to amoxicillin and lincospectin and commonly resistant to tetracycline (884%) and doxycycline (744%). Overall, the results indicate a limited degree of genetic diversity in stx2fharbouring E. coli from pigeons.

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