Avian viral arthritis: antigenic types and immune response.

: Serums from broiler breeders of an integrated broiler operator were examined for precipitin antibodies using antigens prepared from preliminary reovirus serotypes represented by WVU-2937, Reo-25, Reo-59, and Fahey-Crawley virus. The precipitin antibodies were present in most of the flocks. Virus neutralization tests indicated that the reovirus responsible for viral arthritis represented by WVU-2937 was not present in the breeder flocks, but antibodies to Reo-25, Reo-59, and the Fahey-Crawley viruses were present.