Boes, J., Nersting, L., Nielsen, E.M., Kranker, S., Enøe, C., Wachmann, H.C., and Baggesen, D.L.
The prevalence and diversity of Campylobacter jejuniwas investigated in pig herds on farms with and without cattle or poultry production. A bacteriological screening of pig cecal samples from 247 finisher herds was carried out at the slaughterhouse. Subsequently, a follow-up study was conducted in 24 herds (either with or without prior C. jejuniisolation from pigs) in which fecal samples were collected from pigs and, if present, cattle and poultry. Samples were analyzed for presence of Campylobacter, and subsequent analysis included species identification, serotyping, and, for selected strains, pulsed-field gel electrophoresis typing. In the slaughterhouse screening, C. jejuniwas isolated from pigs in 21 (8.5%) herds, but no significant difference in prevalence was found between herd types (pigs, pigs and cattle, pigs and poultry). At the slaughterhouse, C. jejuniand Campylobacter coliprevalence in pigs was 2.3 and 90.1%, respectively. In the follow-up study, herd prevalence of C. jejuniwas 8.3%, whereas C. jejuniand C. coliwere isolated from 0.8 and 92.0% of pigs, respectively. In mixed production herds, C. jejunipredominated in cattle (42.7%) and poultry (31.6%), whereas C. jejuniwas only isolated from 1.3 to 2.5% of pigs in these herds. There were no significant differences in C. jejunior C. coliprevalence in pigs, cattle, and poultry between herds with and without prior C. jejuniisolation at the slaughterhouse. Pulsed-field gel electrophoresis typing did not yield evidence of C. jejunitransmission between cattle or poultry and pigs in mixed production herds. In contrast, pulsed-field gel electrophoresis analysis showed indistinguishable serotypes of C. coliin pigs and cattle in two herds. Verification of C. jejuni–positive pig samples showed that individual pigs can excrete high levels of C. jejuniand that mixed infection with C. jejuniand C. coliwas common in C. jejuni–positive pigs. The results of our study suggest that transmission of C. jejunibetween pigs and cattle or poultry in mixed production herds occurs infrequently. Detection of indistinguishable C. coliisolates in two herds, however, might indicate the existence of low-level transmission between pigs and cattle in herds of mixed production.