Subtyping of Campylobacter spp. strains and their incidence in piglets

Campylobacter spp. are common cause of enteritis in humans, but the routes of transmission and the subtypes of these bacteria responsible for infection are not clearly known, Pigs, which are infected early in life, are known to be symptomless carriers of Campylobacter spp. We evaluated and subtyped 225 samples of rectal swabs from piglets with and without disease by polymerase chain reaction (PCR) and restriction fragment length polymorphism. Little difference was found in the presence of Campylobacter spp. in healthy and diseased piglets: Campylobacter sp. was found in 49% of 225 samples of rectal swabs from piglets with enteric disease, C. coli, C. jejuni and atypical strains representing 81%, 17% and 2%, respectively, and in 41% of rectal swabs from healthy, piglets, C. coli and C. jejuni representing 85% and 15%, respectively. C. coli strains were subtyped from the PCR product with the Hinf1 restriction enzyme, and four subtypes were found and confirmed by sequencing. The most frequent were types III (46%) and I (31%), whereas type II was found in 6% of strains only, and 17% of strains had no cutting site (type IV). Thus, both healthy and sick piglets had a high incidence of Campylobacter spp., which might result in contamination of pork during slaughter. No link was demonstrated between the incidence of individual subtypes of C. coli and the frequency or severity of disease on pig farms.