title: Association between microbiological and serological prevalence of human pathogenic Yersinia spp. in pigs and pig batches.
abstract: Pigs are the main reservoir of human pathogenic Y. enterocolitica, and the microbiological and serological prevalence of this pathogen differs between pig farms. The infection status of pig batches at moment of slaughter is unknown while it is a possibility to classify batches. A relation between the presence of human pathogenic Yersinia spp. and the presence of antibodies could help to predict the infection of the pigs prior to slaughter. Pigs from 100 different batches were sampled. Tonsils and pieces of diaphragm were collected from 7047 pigs (on average 70 pigs per batch). The tonsils were analyzed using a direct plating method and the meat juice collected from the pieces of diaphragm was analyzed by Enzyme Linked ImmunoSorbent Assay. The microbiological and serological results were compared using a mixed-effects logistic regression at pig and batch level. Yersinia spp. were found in 2031 (28.8%) pigs, antibodies were present in 4692 (66.6%) pigs. According to the logistic regression, there was no relation at pig level between the presence of Yersinia spp. in tonsils and the presence of antibodies. Contrarily, at batch level, a mean activity value of 37 Optical Density (OD)% indicated a Yersinia spp. positive farm and the microbiological prevalence in pig batches could be estimated before shipment to the slaughterhouse. This offers the opportunity to classify batches based on their potential risk to contaminate carcasses with human pathogenic Yersinia spp.
authors.affiliation: Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium. Electronic address: gerty.vanantwerpen@ugent.be.
authors.forename: Gerty
authors.initials: G
authors.lastname: Vanantwerpen
authors.affiliation: Unit of Veterinary Biostatistics and Epidemiology, Department of Animal Health, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Berkvens
authors.affiliation: Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Lieven
authors.initials: L
authors.lastname: De Zutter
authors.affiliation: Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Kurt
authors.initials: K
authors.lastname: Houf
mesh_terms: D000818:Animals; D000906:Antibodies; D003964:Diaphragm / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D006801:Humans; D008460:Meat / Q000382:microbiology; D014066:Palatine Tonsil / Q000382:microbiology; D015995:Prevalence; D034421:Sus scrofa; D013552:Swine; D013553:Swine Diseases / Q000097:blood / Q000453:epidemiology* / Q000382:microbiology*; D015009:Yersinia Infections / Q000097:blood / Q000453:epidemiology / Q000662:veterinary*
chemical_list: D000906:Antibodies
keywords: Y. pseudotuberculosis; association; human pathogenic Y. enterocolitica; microbiology; pigs at slaughter; serology