Fatal herpesvirus infection in commercial rabbits.

Acute mortality occurred in two unrelated rabbitries. In the rabbits examined, an unidentified herpesvirus caused lesions that have not been reported previously in this species. The primary lesions were multifocal hemorrhagic dermatitis on the face and back, localized pneumonia, and severe splenic necrosis. Large eosinophilic, intranuclear inclusion bodies that were observed in tissue sections of skin, spleen, and lung were identified as herpes-like viral particles by electron microscopy, and herpesvirus was cultured on rabbit kidney cells. Intramuscular injection of tissue culture fluid containing virus resulted in mortality and severe illness in two seven-week-old domestic rabbits four and six days postinfection, respectively. The gross and microscopic lesions were reproduced and herpeslike viral inclusions were observed in skin lesions. Herpesvirus was recovered from lung, trachea, spleen, liver, and from the thigh muscle at the site of inoculation. The experimental infection also activated severe pasteurella septicemia. The herpesvirus isolate needs further characterization.