†Sónia Ramos and Nuno Silva contributed equally to this study and should be considered as joint first authors.
High prevalence of antimicrobial-resistant Escherichia coli from animals at slaughter: a food safety risk
Article first published online: 27 JUL 2012
Copyright © 2012 Society of Chemical Industry
Journal of the Science of Food and Agriculture
Volume 93, Issue 3, pages 517–526, February 2013
How to Cite
Ramos, S., Silva, N., Caniça, M., Capelo-Martinez, J. L., Brito, F., Igrejas, G. and Poeta, P. (2013), High prevalence of antimicrobial-resistant Escherichia coli from animals at slaughter: a food safety risk. J. Sci. Food Agric., 93: 517–526. doi: 10.1002/jsfa.5814
- Issue published online: 28 JAN 2013
- Article first published online: 27 JUL 2012
- Manuscript Accepted: 20 JUN 2012
- Manuscript Revised: 18 APR 2012
- Manuscript Received: 7 NOV 2011
- antimicrobial resistance;
- Escherichia coli;
- food-producing animals;
- resistance genes
BACKGROUND: There has been concern about the increase of antimicrobial resistant bacteria and protection of animal and public health, along with food safety. In the present study, we evaluate the incidence of antimicrobial resistance among 192 strains of Escherichia coli isolated from faecal samples of healthy food-producing animals at slaughter in Portugal.
RESULTS: Ninety-seven % of the pig isolates, 74% from sheep and 55% from cattle were resistant to one or more antimicrobial agents, with the resistances to ampicillin, streptomycin, tetracycline and trimethoprim–sulfamethoxazole the most common phenotype detected. Genes encoding resistance to antimicrobial agents were detected in most of the resistant isolates. Ninety-three % of the resistant isolates were included in the A or B1 phylogenetic groups, and the virulence gene fimA (alone or in association with papC or aer genes) was detected in 137 of the resistant isolates. Five isolates from pigs belonging to phylogroup B2 and D were resistant to five different antimicrobial agents.
CONCLUSION: Our data shows a high percentage of antibiotic resistance in E. coli isolates from food animals, and raises important questions in the potential impact of antibiotic use in animals and the possible transmission of resistant bacteria to humans through the food chain. © 2012 Society of Chemical Industry