Occurrence of beta-lactamase producing Escherichia coli in healthy and diarrhoeic dogs in Andhra Pradesh, India

Abstract

The present study was carried out to characterize beta-lactam resistance in Escherichia coli isolated from healthy and diarrhoeic dogs. A total of 93 E. coli were isolated from the rectal swabs of 136 dogs (60/92 of healthy dogs and 33/44 of diarrhoeic dogs). Predominant serotypes detected include rough (19 isolates), O141 (5), O9 (2), O126 (2), O128 (2), O15, O20, O35, O49, O63, O85, O101, O116, O117, O118, O119 (1 isolate each) and the rest of 52 isolates were untypable (UT). Disc diffusion method revealed resistance to cefotaxime (41.9%), ceftriaxone (34.4%), ceftazidime (30.1%) and aztreonam (18.2%). Overall frequency of extended spectrum beta-lactamase (ESBL) phenotype was found to be 29% (27/ 93). Beta-lactamase genes detected include bla AmpC (86.0%), bla SHV (30.1%), bla CTX-M group-1 (19.3%), bla TEM (17.2%), bla OXA (13.9%) and bla CTX-M group-2 (7.5%). The study revealed resistance to commonly prescribed beta-lactams, with ESBL phenotype in E. coli of canine origin in Andhra Pradesh, India.