Herpes simplex encephalitis in a domestic rabbit (Oryctolagus cuniculus)

An adult domestic rabbit showing neurological signs was subjected to euthanasia. At necropsy, macroscopical lesions were absent. Histopathologically, extensive lesions were seen, particularly in the cerebral cortex. Non-suppurative meningitis was present and there was lymphocytic and plasmacytic perivascular cuffing in the neuropil. The cerebral cortex showed extensive segmental neuronal and glial necrosis. Within the necrotic areas, large amphophilic intranuclear inclusion bodies were present in neurons and glial cells. Immunohistochemically, neurons and glial cells in the affected areas were labelled by polyclonal antibodies against both herpes simplex virus-1 (HSV-1) and HSV-2. The agent was classified as HSV-1 by polymerase chain reaction analysis. This is only the second reported natural case of herpes simplex infection in a rabbit.