Bovine digital dermatitis (DD) is a leading cause of lameness in dairy cattle throughout the world. Despite more than 40 years of research, the definitive etio- logic agent associated with the disease pro- cess is still unknown. Previous studies have demonstrated that multiple bacterial species are associated with lesions, with spirochetes being the most reliably identified organism.

According to the most recent National Animal Health Monitoring System survey of U.S. dairy farms, lameness is the second most common health problem identified in dairy cattle. DD was found to be the primary cause of lameness within the study herds, account- ing for 61.8% of the lameness in bred heifers and 49.1% of the lameness in cows. Recently, the condition has become increasingly com- mon in feedyard cattle as well, particularly in heavy cattle nearing slaughter weights, although it can be seen in cow–calf opera- tions as well.