Critical Review: Future Control of Blackhead Disease (Histomoniasis) in Poultry.

Blackhead disease (histomoniasis) currently has no efficacious drug approved for use in poultry in the United States. Both chickens and turkeys can get the disease, but mortality is most often associated with turkeys. The lack of any approved therapies for blackhead is of concern, especially in the case of valuable turkey breeder candidate flocks. Due to the availability of efficacious drugs for many years, research focused on blackhead was minimal. However, without any drugs or reliable additives, blackhead will continue to be an issue in turkeys and broiler breeder chickens. The American Association of Avian Pathologists annual meeting in San Antonio, Texas, August 6-9, 2016, held a mini-symposium on blackhead. The mini-symposium included university researchers and industry veterinarians discussing blackhead in the United States and Europe including insights on the disease pathogenesis and epidemiology, as well as an update on the current state of blackhead in the United States since the removal of nitarsone from the market in January 2016. This review summarizes the information presented at the mini-symposium and discusses current control measures in an era without efficacious drugs.