Brachyspira in dogs: risk factors of shedding in central Germany and longitudinal study of an infected kennel

Brachyspira (B.) pilosicoli is a zoonotic pathogen, able to infect different animal species such as pigs, poultry, and rodents, causing intestinal spirochetosis. An association of gastrointestinal clinical signs, such as diarrhea, with the isolation of B. pilosicoli from fecal samples or rectal swabs has not been proven in dogs. Other Brachyspira species commonly isolated from dogs, such as “B. canis” and “B. pulli”, are considered commensals. This study investigated the occurrence of different Brachyspira species in rectal swabs and fecal samples in an independent canine cohort in central Germany. These included samples from shelter dogs, hunting dogs, and dogs presenting at regional small animal practices with various clinical signs. Data about the dogs, including potential risk factors for Brachyspira isolation, were obtained using a standardized questionnaire. The study also longitudinally investigated a colony of Beagle dogs for Brachyspira over 5 years. The rate of Brachyspira spp. isolation was 11