Spatial distribution of the emerging foodborne pathogen Arcobacter in the gastrointestinal tract of pigs

Pigs are important reservoirs for Arcobacter. Since 1978, Arcobacter species have been associated with reproduction disorders, but excretion by clinically healthy pigs has been frequently reported as well. Information on Arcobacter colonization of the porcine gastrointestinal tract is lacking. In the present study, gastrointestinal tracts of 12 pigs were collected, and the content and mucus of eight sections were examined. Arcobacters were enumerated and isolated by a selective quantitative and qualitative method, respectively, and identified by multiplex-polymerase chain reaction (PCR). Their genetic diversity was examined by enterobacterial repetitive intergenic consensus PCR and pulsed-field gel electrophoresis. Arcobacter species were isolated from at least two gastrointestinal sections of all pigs in levels up to 10(5) colony-forming units (CFU) g(-1) in content and 10(4) CFU g(-1) in mucus. Characterization of the isolates revealed a high degree of genotypic diversity. In general, the highest counts, and greatest species and strain diversity was obtained from the large intestine, and especially from the rectum. Though Arcobacter strains were mostly detected in one gastrointestinal section, several unique strains were also recovered from the content and/or mucus of various gastrointestinal sections of individual pigs. In the gastrointestinal tract, Arcobacter is present with species distributions, numbers, and strain heterogeneity comparable to those reported on porcine carcasses post slaughter, thus confirming the potential route of transmission to carcasses by fecal contamination during processing.