Abstract
Homologous anti-staphylococcal sera passively potentiated the development of experimental staphylococcal synovitis infection of chickens. These antisera obtained from chickens hyperimmunized with live Staphylococcus aureus were selected according to their immune adherence and agglutinating properties. While the agglutinins rose steadily for 11 weeks during the hyperimmunization schedule, the immune adherence antibody titers reached a peak at 8 weeks and dropped to almost zero 2 to 4 weeks later. The enhancement activity of these antisera was associated with a relatively high level of immune adherence antibodies and seemed not to be correlated with their agglutinin titers.