Submitted to: Food Safety Consortium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/14/1997
Publication Date: N/A
Technical Abstract: Yersinia enterocolitica is the causative agent of human yersiniosis. Swine have been implicated as the principal reservoir for human pathogenic Y. enterocolitica. The purpose of this study was to optimize enrichments and to develop and evaluate a PCR-based ELISA to detect Y. enterocolitica in pigs. Of the three enrichments evaluated, ITC provided optimal growth of Y. enterocolitica. All serotypes currently identified in the U.S. grew on this media. The ail gene is a chromosomally-encoded virulence factor unique to Y. enterocolitica and was used as the target in the PCR ELISA assay. The PCR ELISA for the ail gene amplified only Y. enterocolitica and not other Yersinia or enteric bacterial reference strains. The assay was used to screen pigs obtained from three premises in Iowa. Swine fecal samples and tonsils were enriched in ITC and plated to selective agar supplemented with cefsulodin, irgasan, and novobiovin (CIN). Typical "bull's eye" colonies were picked and verified as Y. enterocolitica with PCR ELISA. Y. enterocolitica was detected in 67% of tonsil samples obtained from farm I (n=30 pigs). It was not detected in tonsillar samples from farm II (n=58 pigs) or from swine raised in confinement at NADC (n=19 pigs). This study demonstrates the utility of the PCR ELISA in confirming pathogenic Y. enterocolitica in livestock after ITC enrichment.