Characterization of shiga-toxin producing E.coli (STEC) and Enteropathogenic E. coli (EPEC) from domestic animals for virulence and colonisation factors and their antimicrobial resistance

Abstract

Aim: To determine the occurrence and molecular characterization of Shiga toxin-producing E. coli (STEC) and Enteropathogenic E. coli (EPEC) from different domestic animals for serogrouping, virulence factors and their antibiotic resistance from Jammu region. Methodology: Faecal samples were collected from 200 different animals including calves (39), rabbits (24), dogs (38), slaughtered pigs (22), poultry (41), sheep and goat (36). All the 200 strains were screened for the presence of stx1, stx2 and eae genes by m-PCR and screening of confirmed EPEC isolates with respect to their serogroup, virulence factors (bfpA, astA and ecpA genes) by PCR and antibiotic resistance. Results: Of total 200 E. coli isolates, 38 (19.00%) were detected as EPEC and 28 (14.00%) as STEC. 5 (12.82%), 17 (43.58%) isolates from calves and 12 (33.33%), 11 (30.55%) isolates from sheep were found as EPEC and STEC, respectively. In rabbits, pigs and dogs, 6 (25.0%), 10 (45.45%) and 5 (13.15%) isolates were detected as EPEC, respectively. The most predominant EPEC serogroups were O88 (36.84%), O118 (18.42%). All 38 EPEC (100%) isolates carried ecpA gene and 18 (47.36%) isolates carried astA gene. Of 38 EPEC, only 5 (13.15%) isolates from dog carried bfpA gene, therefore considered as typical EPEC and 33 (86.84%) isolates were designated as atypical EPEC. Antimicrobial sensitivity test (AST) of 38 EPEC isolates showed resistance to nalidixic acid (55.26%), kanamycin (42.10%) followed by streptomycin (42.10%), doxycycline hydrochloride (28.94%), ciprofloxacin (13.15%), tetracycline (13.15%). Surprisingly, all the 38 isolates were sensitive to ampicillin.