EXPERIMENTAL-INFECTION OF BROILER AND LEGHORN CHICKENS WITH VIRULENT AND AVIRULENT ISOLATES OF HEMORRHAGIC ENTERITIS VIRUS

The effects of virulent and avirulent isolates of hemorrhagic enteritis virus were studied in Leghorn and broiler chickens. The viruses caused subclinical infections in both strains of birds. The avirulent isolate produced enlarged spleens, inclusion bodies and antibody in all inoculated Leghorns. In broilers the avirulent virus produced infection in only half of the inoculated birds. Inclusion bodies were widely dispersed in the spleens of both types of birds. The virulent virus produced infection in all inoculated birds of both strains. Inclusion bodies were numerous in the spleens of Leghorn birds and were widely scattered in the spleens of broilers.