Cyclophosphamide-Induced Immunosuppression Demonstrated in Pasteurella multocida-Vaccinated Chickens

Abstract
Vaccinated cyclophosphamide-treated chickens were more susceptible to challenge infection than were vaccinated untreated chickens. Antibody titers were greatly reduced in cyclophosphamide-treated chickens. Apparently the presence of specific antibody is important in determining the ability of chickens to resist Pasteurella infection.