Antimicrobial resistance and molecular characterisation of E. coli from poultry in Eastern India.

In this study 252 poultry samples comprised of poultry meat (n = 228) and poultry eggs (n = 24) were screened for the isolation of Escherichia coli (E. coli). A total of 62 E. coli isolates were recovered from poultry meat. The E. coli isolates belonged to different serogroups based on ‘O’ serotyping of the isolates viz O29 (10.8%), O8 (7.7%), O40 (6.15%), O2 (4.61%), O60 (3.08%), O106 (3.08%), 42 (1.54%), O 87 (1.54%), and 01 serotypes of O1, O7, O30, O45, O59, O66, O105, O1116, O136, O141, O147, O148, O166, and O172. Sixteen (24.62%) of the isolates were UT (untypable) and 6 (9.23 %) were rough types. Molecular characterisation of the isolates was performed, targeting stx1 and stx2 virulence gene fragment. Out of 62 E. coli isolates, 10 (16.12%) were carrying virulence gene stx2, whereas none of the isolate was carrying stx1 gene. The E. coli isolates showed wide variation in resistance pattern against the antimicrobial agents that we used (9-90%). Among E. coli isolates, maximum resistance was observed against cefuroxime (89.1%) and penicillin (89.4%), followed by ampicillin (80.43%), vancomycin (74.1%), co-trimoxazole (73.1%), cephalothin (60.8%), ceftriaxone (28.2%), tetracycline (17.4%), gentamicin (13%), amikacin (13.04%), ofloxacin (13%), and ciprofloxacin (6.5%). A high degree of susceptibility was observed against amikacin (84.7%) and ciprofloxacin (76%) followed by gentamicin (71.73) and ofloxacin (60.86%). High multiple antibiotic resistances were observed and a total of 34 resistance patterns were identified.