Sheep carrying pathogenic Yersinia enterocolitica bioserotypes 2/O:9 and 5/O:3 in the feces at slaughter

•Sheep shed Y. enterocolitica bioserotypes 2/O:9 and 5/O:3 in the feces.•ail-positive Y. enterocolitica bioserotype 1A strains found in sheep.•Isolation and identification of bioserotype 5/O:3 is very challenging.•Genetic diversity of bioserotypes 2/O:9 and 5/O:3 was very limited.•Susceptibility to antimicrobial agents was very high. Yersinia enterocolitica is a heterogeneous species including non-pathogenic strains belonging to biotype 1A and pathogenic strains belonging to biotypes 1B and 2–5. Pathogenic strains of biotypes 2–4 carrying the ail virulence gene have frequently been isolated from domestic pigs at slaughter. In sheep, mostly non-pathogenic biotype 1A strains have been reported. In our study, the prevalence of ail-positive Y. enterocolitica was studied by PCR and culturing in 406 young sheep (