a1 Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
a2 Research and Development Department, National Food Administration, Uppsala, Sweden
Rodents are a potential source of pathogenic Yersinia enterocolitica and Y. pseudotuberculosis. In order to study this, 190 rodents were captured and sampled on seven pig farms (n=110), five chicken farms (n=55) and six other locations (n=25) in Sweden. Pigs from three of the pig farms were also sampled (n=60). Pathogenic Y. enterocolitica was detected by TaqMan PCR in about 5% of rodent samples and 18% of pig samples. Only rodents caught on pig farms tested positive for the pathogen. Y. enterocolitica bioserotype 4/O:3 strains isolated from the rodent and pig samples were compared by pulsed-field gel electrophoresis and revealed a high degree of similarity, which was confirmed by random amplified polymorphic DNA. Y. pseudotuberculosis was only detected in one rodent sample. Thus, rodents may be vectors for the transmission of pathogenic Y. enterocolitica to pigs, acting as carriers rather than a reservoir, and should therefore remain an important issue in hygiene control measures on farms.
(Accepted October 04 2010)
(Online publication November 15 2010)
c1 Author for correspondence: Dr A. Backhans, Department of Clinical Sciences, Division of Diagnostics and Large Animal Clinical Sciences, Swedish University of Agricultural Sciences (SLU), Box 7054, SE-75007 Uppsala, Sweden. (Email: Annette.Backhans@kv.slu.se)