<i>In vitro</i> comparative activity of ciprofloxacin and enrofloxacin against clinical isolates from chickens in Benue State, Nigeria

This study compares the in vitro activities of enrofloxacin and its main metabolite ciprofloxacin against clinical Escherichia coli and non-lactose fermenting enterobacteria isolates from chickens. Ten (10) Escherichia coli and 8 non lactose fermenting enterobacteriaceae species isolated from a pool of clinical cases at the Microbiology Laboratory of the Veterinary Teaching Hospital, University of Agriculture Makurdi were used in this study. Ten-fold serial dilution of 10 varying concentrations (0.1-50μg/mL) of enrofloxacin and ciprofloxacin were tested against the isolates in vitro by Bauer’s disc-diffusion method to determine and compare their antimicrobial activities against the isolates. The 18 isolates tested were susceptible to both enrofloxacin and ciprofloxacin, and their mean values in the susceptibility of Escherichia coli and non-lactose fermenters were significantly different (p < 0.01). The study concluded that the clinical isolates are susceptible to both enrofloxacin and ciprofloxacin though ciprofloxacin exhibit higher activity. Comparatively, ciprofloxacin was found to be more potent than enrofloxacin and the difference statistically significant. Ciprofloxacin was recommended as a better choice in the treatment of bacterial infections of chicken in this area compared to enrofloxacin. It was also recommended that proper steps should be taken in the administration of antimicrobials so as to reduce the incidences of bacterial resistance.Keywords: Escherichia coli, Non-lactose fermenter, Antimicrobials, Ciprofloxacin. Enrofloxacin, Chicken