Investigation on the presence of Escherichia coli producing extended-spectrum β-lactamase isolated from healthy chicken in Vinh Long province

Abstract

This study was carried out to determine the presence of E. coli producing extended-spectrum β-lactamase (ESBL) and ESBL encoded gene from 120 fecal samples of the healthy chickens, which were collected from 24 chicken raising households in Vinh Long province. The studied result showed that 34.16% (41/120) of the samples contained E. coli producing ESBL. 101 E. coli strains producing ESBL were selected for the investigation of their susceptibility to 13 antibiotics by the disc diffusion method. The resistance of the E. coli strains producing ESBL was most frequently observed to cefaclor (96.04%), ampicillin (92.08%), cefuroxime (86.14%), trimethoprim+sulfamethoxazole (71.29%), streptomycin (69.31%), ofloxacin (58.4%), gentamicin(54.45%) and norfloxacin (52.48%). However, these E. coli strains were highly sensitivewith amikacin (99.01%), doxycyline (90.09%) and fosfomycin (82.18%). 30 multi-resistant isolates were selected for determination of bla CTX-M, bla TEM and bla SHV genes by polymerasechain reaction (PCR) with the specific primers. The tested result showed that 22 isolates contained at least one ESBL encoded gene and these genes were not detected in 8 isolates. The Bla CTX-M and bla TEM genes were frequently detected in the tested E. coli isolates (70% and 46.67% respectively). Only 6.67% E. coli containing the bla SHV gene was detected. This is the first report for the E. coli strains producing ESBL from the healthy chickensin Vinh Long province.