Abstract
Anaerobic spirochetes of the genus Brachyspira are the cause of swine dysentery (SD) and other forms of colitis in swine and other species. These diseases have a worldwide distribution, and SD is one of the most economically significant endemic bacterial infections of swine. Losses mainly occur in the grower–finisher phase as a result of severe growth depression and medication costs. Increased resistance to antimicrobials and a lack of commercial vaccines exacerbate the problems veterinarians and producers face when trying to control disease caused by Brachyspira species. The recent emergence and recognition of atypical Brachyspira strains complicate surveillance and have made it more difficult to ascertain herd health status. This chapter presents current knowledge on the etiology, epidemiology, pathogenesis, and means to prevent and control SD and Brachyspira colitis. New information on Brachyspira interactions with the colonic microbiota and the host response to spirochete colonization is also provided.