Studies of multi-drug resistant (MDR) E.coli in Australia indicate a high probability of strain and plasmid diversity.
The outcome reflects various selection pressures at the individual farm level rather than emergence and lateral spread of MDR resistant/virulent clones.
This was the conclusion of research at the School of Veterinary Science, University of Queensland, Brisbane, Australia.
This study aimed to characterise antimicrobial resistance and virulence genes in multi-drug resistant enterotoxigenic Escherichia coli isolates collected from porcine post-weaning diarrhoea cases in Australia, between 1999 and 2005.
A total of 117 isolates were serotyped, antibiogram-phenotyped for 12 antimicrobial agents and genotyped by PCR for 30 plasmid-mediated antimicrobial resistance genes (ARGs), 22 intestinal and 38 extraintestinal E. coli virulence genes (VGs).
Nine serogroups were identified.
The study was carried out by M.G. Smith, D. Jordan, T.A. Chapman, J.J. Chin, M.D. Barton, T.N. Do, V.A. Fahy, J.M. Fairbrother, D.J. Trott DJ and was called Antimicrobial resistance and virulence gene profiles in multi-drug resistant enterotoxigenic Escherichia coli isolated from pigs with post-weaning diarrhea.
It was published in Veterinary Microbiology, October 2010.