Colonic infection by Bilophila wadsworthia in pigs

Bilophila wadsworthia is a common inhabitant of the human colon and has bee n associated with appendicitis and other local sites of inflammation in hum ans. Challenge-exposure or prevalence studies in laboratory and other anima ls have not been reported. B, wadsworthia is closely related phylogenetical ly to Desulfovibrio sp, and Lawsonia intracelluaris, which are considered c olon pathogens, We developed a PCR specific for B. wadsworthia DNA, Samples of bacterial DNA extracted from the feces of pigs on sin farms in Australi a and four farms in Venezuela were examined, Specific DNA of B. wadsworthia was detected in the feces of 58 of 161 Australian and 2 of 45 Venezuelan p igs, results comprising 100% of the neonatal pigs, 15% of the weaned grower pigs, and 27% of the adult sows tested, Single-stranded conformational pol ymorphism analysis of PCR product DNA derived from pigs or front known huma n strains showed an identical pattern. Histologic examination of the intest ines of weaned B, wadsworthia-positive pigs found no or minor specific lesi ons in the small and large intestines, respectively. B. wadworthia is appar ently a common infection in neonatal pigs, but its prevalence decreases aft er weaning. The possible rule of B. wadsworthia as an infection in animals and in human colons requires further study.