Abstract

Isolation of multidrug resistant Escherichia coli from diseased livestock is becoming rampart from samples submitted for disease diagnostic purposes in some Tertiary Veterinary Teaching Hospitals in Nigeria. In order to evaluate the possible roles of commensal E. coli from apparently healthy animals in the epidemiology of drug resistant pathogens, antibiotic resistance status of 240 E. coli isolated from 300 rectal swab from apparently healthy cattle from a major cattle market in Ibadan, Oyo State, South West Nigeria (a location very close to two of the Veterinary Teaching Hospitals), were grown aerobically at breakpoint concentration  for ciprofloxacin, cefepime, chloramphenicol, tetracycline, ampicillin, kanamycin, streptomycin and nalidixic acid (all obtained from SIGMA-ALDRICH) according to standard method by Clinical Laboratory Standards Institute. A very high level of resistance was observed in all the antibiotics studied, with the highest resistance of 97% for kanamycin and 96.7, 95.8, 73.8, 72.5, 61.7, 56.3 and 51.3% for ampicillin, chloramphenicol, tetracycline, cefepime, nalidixic acid, streptomycin and ciprofloxacin, respectively. The high resistance observed in the commensal E. coli could be attributed to antibiotic selective pressure due to often abuse/misuse of the drugs on the cattle. The findings in this work are of public health importance because these multidrug resistant E. coli can transmit resistance to other pathogenic bacteria of livestock and human pathogen.

Key words: Antimicrobial, resistance, healthy cattle, isolated.