Antibiotic resistance among ETEC, VTEC and non-toxigenic Escherichia coli strains isolated from piglets

Antimicrobials are used in animals as growth promoters (in subterapeutic doses), for disease prevention (after commingling of animals from differnt farms) or therapeuticaly (for treatment of infection). Extensive studies over the years have shown that imprudent use of antimicrobials resulted with an increase of prevalence and distribution of multiple antimicrobial resistant infection in animals, with possible impact on human health. The aim of our study was to determine the extent in which enterotoxigenic Escherichia coli (ETEC) and verotoxigenic Escherichia coli (VTEC) isolates are resistant to a different range of antimicrobial agents, in comparison to the resistance among non-toxigenic Escherichia coli strains. The 115 E. coli strains isolated from piglets were tested for their ability to produce enterotoxins (termolabile -LT or/and termostabile - ST) and vero toxin (VT) by the OXOID test kits, and for their sensitivity to 17 antimicrobials agents by disc diffusion method. Of the 115 E. coli strains used in this study, 99 (86.1 %) were enterotoxigenic or/and verotoxigenic, and 16 (13.9 %) were non-toxigenic. All of tested strains demonstrated multiple resistance, and there was no significant difference in the antimicrobial sensitivity between toxigenic and non-toxigenic isolates.