Abstract
Neutralization kinetic rates were compared between five avian and three human reoviruses and their specific antiserums. Antigenic similarities were not noted between the human and avian reoviruses studied. Antigenic similarities were found between a reovirus isolated from a chicken with Marek's disease, and the Fahey-Crawley virus, avian arthritis virus, and a turkey reovirus isolate designated as BC-3. The Fahey-Crawley virus was found to be antigenically similar to BC-3.