Characterization of Yersinia enterocolitica isolated from the oral cavity of swine in Slovakia.

Yersinia enterocolitica was detected in 160 of 2760 examined samples that were prepared from dental cavity of 920 pigs. From the isolates 49 strains were characterized with respect to their genetic and phenotypic markers of virulence. All strains were belonging to serogroup 0:3, biovar 4. Forty-one isolates (84%) harboured the virulence plasmid detected by DNA colony hybridization. Of the other assays of virulence--autoagglutination, binding of crystal violet, pyrazinamidase activity, calcium dependence and Congo red binding--the latter two exhibited the best correlation with the detected presence of plasmid DNA.