EN
The purpose of the study was to evaluate changes in the antimicrobial susceptibility of Yersinia (Y.) enterocolitica strains to various chemotherapeutic groups. In total, 103 Y. enterocolitica strains were used. They belonged to biotypes 1A, 3, 4 and serotypes O:3, O:5, O:6, O:7,13, O:8, O:9, and were isolated in the years 2000 and 2007 from pigs in farms located in north-eastern Poland. Twenty-six chemotherapeutics of various groups were applied: quinolones, β-lactams, aminoglycosides, tetracyclines, chloramphenicol, colistin, tiamulin, nitrofurantoin, sulphonamides, and sulphamethoxazole/trimethoprim. Strain sensitivity was evaluated in vitro by the standardized disc-diffusion method according to CLSI recommendations. The study showed that the sensitivity profile of Y. enterocolitica strains isolated from pigs in Poland in the years 2000 and 2007 underwent significant changes during this interval, that reveal a tendency for increasing resistance to some chemotherapeutics used in veterinary treatment. Considering the hazard to public health caused by the wide prevalence of these bacteria in pig population, as well as the need to ensure the efficacy of yersiniosis treatment, the phenomenon of Y. enterocolitica acquiring drug resistance to chemotherapeutics should be systematically monitored.