Antibiotic resistance of Escherichia coli, Listeria and Salmonella isolates from retail meat tables in Ibadan municipal abattoir, Nigeria

Abstract

Antibiotics sensitivity test was assayed on thirty (30) isolates (10 each for Escherichia coli, Listeria and Salmonella) from retail meat (beef) tables in Ibadan municipal abattoir, Nigeria. The isolates were tested for sensitivity for eight (Listeria) and ten (Escherichia coli and Salmonella) commonly used antibiotics using Bauer-Kirby disc diffusion assay. Antibiotics sensitivity profile expressed in mean zone of inhibition (mm) ± standard error of mean showed that all the isolates were resistant to three or more antibiotics. All the isolates were resistant to tetracycline. The incidence of antibiotic resistance in virulent strains: E. coli O157:H7 (60%) and Salmonella typhi (60%) was higher than the non virulent strains: E. coli (40%) and Salmonella spp, (50%), respectively. The overall incidence of antibiotics resistance in Listeria strains was relatively lower (37.5%) than the other pathogens. The high rate of resistance revealed abuse of antibiotic usage in cattle. The public health significance of these findings is that the resistant strains from meat tables may find their way into human population through food chain and occupational exposure.

Key words: Meat table, Escherichia coli, Listeria, Salmonella, antibiotics  sensitivity, abattoir.