Genotyping Campylobacter jejuni strains isolated from the gut and oviduct of laying hens

Campylobacter jejuni frequently colonizes the avian intestine. Recent evide nce suggests chat this organism can also colonize the oviduct of laying hen s. However, the source and role of this colonization are unknown. Isolates from the ceca, cloacae, and oviducts of 11 laying hens in three intensive e gg-producing flocks were genotyped by Fin typing with the restriction fragm ent length polymorphism of the polymerase chain reaction product of the fla A and flaB genes (fla typing) and pulsed-field gel electrophoresis (PFGE). A diversity in fla types and PFGE types was observed within and between flo cks. Individual birds could be colonized by different genotypes at various intestinal and oviduct sites. However, the oviduct of individual birds appe ared to be colonized by only one genotype at the time of sampling. In two b irds, matching isolates investigated from the intestinal and reproductive t racts were genotypically identical bur. different from those oviduct isolat es found in other birds in the same flock. Interestingly, not all ceca isol ates appeared to be equally able to colonize the oviduct. These results sug gest that oviduct colonization may result from ascending infection via the cloaca and that some strains of C. jejuni may be better adapted than others to oviduct colonization.