title: Contamination of freshly slaughtered pig carcasses with enteropathogenic Yersinia spp.: Distribution, quantification and identification of risk factors.
abstract: A cross-sectional survey was undertaken to determine the overall prevalence of enteropathogenic Yersinia spp. in the tonsils, feces and on carcasses of pigs at slaughter. Moreover, factors associated with Yersinia contamination of freshly eviscerated pig carcasses were studied. Yersinia enterocolitica serotype O:3 was isolated from the tonsils and feces of 55.3% and 25.6% of pigs, and Y. pseudotuberculosis from 1.4% and 0.6%, respectively. The pathogens were also recovered from 39.7% of carcass surfaces post-evisceration. The highest prevalence was found at the mandibular region (28.9%), followed by the sternal region (16.4%), pelvic duct (7.8%), and split surface near the sacral vertebrae (6.9%). Regarding the quantification of the pathogen, the median concentration of pathogenic Y. enterocolitica was 4.14l og10 CFU/g in tonsils with countable numbers (n=143) and 2.80 log10 CFU/g for fecal samples with countable numbers (n=26). The quantitative load on the carcass surface was generally low as the majority of the carcass samples (97.0%) had Yersinia concentrations below the detection limit of enumeration (<1.30 log10 CFU/100 cm(2)). The initial presence of Y. enterocolitica in the tonsils and/or feces was significantly associated with carcass contamination at all sampled areas. Other risk factors for carcass contamination are the splitting of the head together with the carcass, and incision of the tonsils during removal of the pluck. Small adaptations in slaughter practices and the training of slaughterhouse personnel to respect basic hygienic instructions may diminish carcass contamination with enteropathogenic Yersinia.
authors.affiliation: Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Merelbeke, Belgium. Electronic address: inge.vandamme@ugent.be.
authors.forename: I
authors.initials: I
authors.lastname: Van Damme
authors.affiliation: Prince Leopold Institute of Tropical Medicine, Department of Biomedical Sciences, Antwerp, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Berkvens
authors.affiliation: Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Merelbeke, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Vanantwerpen
authors.affiliation: Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Merelbeke, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Baré
authors.affiliation: Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Merelbeke, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Houf
authors.affiliation: University of Louvain, Faculty of Medicine, Microbiology Unit, Brussels, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Wauters
authors.affiliation: Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Merelbeke, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: De Zutter
mesh_terms: D000003:Abattoirs; D000818:Animals; D003430:Cross-Sectional Studies; D005243:Feces / Q000382:microbiology; D008460:Meat / Q000382:microbiology*; D014066:Palatine Tonsil / Q000382:microbiology; D015995:Prevalence; D012307:Risk Factors; D013552:Swine / Q000382:microbiology*; D013553:Swine Diseases / Q000453:epidemiology; D015009:Yersinia Infections / Q000453:epidemiology; D015008:Yersinia enterocolitica / Q000145:classification / Q000302:isolation & purification*; D015011:Yersinia pseudotuberculosis / Q000145:classification / Q000302:isolation & purification*
keywords: Carcass contamination; Enteropathogenic Yersinia spp.; Pig; Pork; Slaughterhouse