Abstract
A study of experimental infectious canine hepatitis in dogs by means of specific fluorescent antibody indicates that the intranuclear inclusions of this disease contain high concentrations of viral antigen. The increase in virus in the nuclei, as indicated by the accumulation of specific antigenic material, begins on the nuclear membrane and spreads from there to the interior of the nucleus, with the gradual formation of larger granules. Subsequently there appear the homogeneous inclusion bodies characteristic of this infection.