Abstract
Histopathological studies were conducted on diseased hirame (Paralichthys olivaceus) naturally infected with Rhabdovirus olivaceus (hirame rhabdovirus ; HRV) during 1984 and 1985 in Hyogo Prefecture and Hokkaido. Studies of hirame artificially infected with HRV (strain 8401-H) were also conducted.
Signs of infection were congestion of the gonad, focal hemorrhage of skeletal muscle and fins, and accumulation of ascitic fluid.
Histopathologically, the kidney indicated necrotic changes by nuclear degeneration of hematopoietic cells and hemorrage in the interstitial tissue. The spleen showed necrosis and hemorrhage in the pulp, and skeletal muscle revealed hyperemia and hemorrhage of capillary vessels. Hyperemia and hemorrhage were observed in the interstitial tissue of the seminiferous duct, ovarian lamella, and in the connective tissues around the seminal duct and oviduct of the testis and ovary. Mucosa of alimentary tract showed hyperemia and hemorrhage. No pathological changes were observed in the liver.
