Detection of pathogenic Escherichia coli and Staphylococcus aureus from cattle and pigs slaughtered in abattoirs in Vhembe District, South Africa

Abstract

Pathogenic food-borne bacteria have been associated with severe morbidity and mortality in humans and animals. This study was aimed at determining the prevalence of Staphylococcus aureus, Salmonella spp., and Escherichia coli present in cattle and pigs slaughtered in selected abattoirs in Vhembe District and at determining the susceptibility of the isolates to antibiotics. A total of 176 swab samples (28 cattle and 16 pigs) of the rump, flank, brisket, and neck of the animals were analyzed using standard microbiological methods. E. coli isolates were genotyped to detect pathogenic strains. Of the 176 samples, 104 (67.5%) were positive for E. coli and 50 (32.5%) for S. aureus. There was no statistically significant difference (P > 0.05) in the isolation rate from the different animal parts or abattoirs. Overall, 14/104 (13.46%) of the E. coli isolates were pathogenic strains which included enteropathogenic E. coli (EPEC) (bfpA) 1.9%, enterotoxigenic E. coli (ETEC) (LT) 3.8%, and enteroaggregative E. coli (EAEC) (aaiC) 7.6%. E. coli isolates were resistant (100%) to vancomycin and bacitracin. S. aureus (100%) were resistant to oxacillin and nalidixic acid. The presence of resistant strains of these bacteria in food of animal origin could serve as important vehicles transmitting these bacteria to humans. This finding is of epidemiological significance.