Original scientific paper

Frequency of antimicrobial resistance of E. coli isolates from dairy farms in Trinidad by source and presence of virulence markers

Rohini Roopnarine ; School of Veterinary Medicine, Faculty of Medical Sciences, University of the West Indies, St. Augustine, Trinidad and Tobago
David Ammons ; School of Veterinary Medicine, Faculty of Medical Sciences, University of the West Indies, St. Augustine, Trinidad and Tobago
Abiodun Adewale Adesiyun ; School of Veterinary Medicine, Faculty of Medical Sciences, University of the West Indies, St. Augustine, Trinidad and Tobago

Abstract

A cross-sectional study was conducted on 50 dairy farms in Trinidad. Faecal samples were collected from cows, calves and humans; rectal swabs from pet dogs as well as bulk milk and milking parlour effluent. The disc diffusion method was used to detect resistance to eight antimicrobial agents amongst 500 isolates of Escherichia coli. The vero cell assay was used for verocytotoxin (VT) and heat-labile (LT) detection while the polymerase chain reaction (PCR) was used to detect VT genes amongst selected isolates. In Waller Field, 70.0% (168 of
240) of the E. coli isolates exhibited resistance to one or more antimicrobial agents compared with 83.5% (217 of 260) of the isolates from Carlsen Field (P <0.001; χ2). Overall, the frequency of resistance of isolates was highest to streptomycin (72.7%) and lowest to the fluoroquinolones (0.2%). Of a total of 130 E. coli isolates positive for O157 strain, VT gene, VT and or LT production, 104 (80.0%) were resistant. Resistance amongst E. coli strains with virulence markers could pose therapeutic problems on dairy farms in Trinidad.

Keywords

antibiograms; E. coli; dairy farms; Trinidad

Hrčak ID:

45254

URI

https://hrcak.srce.hr/45254

Publication date:

16.6.2009.

Article data in other languages: croatian

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