title: Sheep carrying pathogenic Yersinia enterocolitica bioserotypes 2/O:9 and 5/O:3 in the feces at slaughter.
abstract: 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 (<1year of age) and 139 older sheep at slaughter in Finland. When using PCR, the detection rate was 11% (45/406) in young sheep originating from 11 (18%) farms. Surprisingly, Y. enterocolitica belonging to bioserotypes 2/O:9 and 5/O:3, carrying both chromosomal and plasmid-borne virulence genes, were isolated from the fecal samples of 10 (2%) and 23 (4%) sheep, respectively. All isolates of bioserotypes 2/O:9 (19 isolates) and 5/O:3 (53 isolates) carried the chromosomal virulence genes ail, inv, ystA, and myfA, and almost all isolates (71/72) also carried the virulence genes virF and yadA located on the virulence plasmid. The isolates showed high susceptibility to tested antimicrobials and low genetic diversity by PFGE. Y. enterocolitica bioserotype 5/O:3 is a very rare bioserotype, and has earlier only sporadically been reported in European wildlife and in sheep in Australia and New Zealand. Bioserotype 2/O:9 is a common bioserotype found in humans with yersiniosis, and has sporadically been isolated in wild and domestic animals.
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, P.O. Box 66, Agnes Sjöbergin katu 2, 00014 University of Helsinki, Finland.
authors.forename: Suvi
authors.initials: S
authors.lastname: Joutsen
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, P.O. Box 66, Agnes Sjöbergin katu 2, 00014 University of Helsinki, Finland.
authors.forename: Kirsi-Maria
authors.initials: KM
authors.lastname: Eklund
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, P.O. Box 66, Agnes Sjöbergin katu 2, 00014 University of Helsinki, Finland.
authors.forename: Riikka
authors.initials: R
authors.lastname: Laukkanen-Ninios
authors.affiliation: Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272 CH-8057 Zürich, Switzerland.
authors.forename: Roger
authors.initials: R
authors.lastname: Stephan
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, P.O. Box 66, Agnes Sjöbergin katu 2, 00014 University of Helsinki, Finland. Electronic address: maria.fredriksson-ahomaa@helsinki.fi.
authors.forename: Maria
authors.initials: M
authors.lastname: Fredriksson-Ahomaa
mesh_terms: D000818:Animals; D002353:Carrier State; D005243:Feces / Q000382:microbiology*; D065288:Serogroup; D012756:Sheep; D012757:Sheep Diseases / Q000382:microbiology*; D015009:Yersinia Infections / Q000382:microbiology / Q000662:veterinary*; D015008:Yersinia enterocolitica / Q000235:genetics
keywords: Biotype; Feces; Sheep; Yersinia enterocolitica