VIRAL DEFORMITY OF YELLOWTAIL FINGERINGS

A new epizootic characterized by death with a deformity of the body oc curred in cultured yellowtail fingerings, Seriola quinqueradiata. A vi rus was isolated from the diseased fish. The virus replicated and prod uced cytopathic effects on CHSE-214, EPC, BF-2, FHM, EK-1 and RTG-2 ce lls. Treatment with IUdR indicated that the virus contained RNA. Elect ron microscopy revealed that the virions were non-enveloped, hexagonal in shape with diameter of 65-69nm. Intraperitoneal injection of the v irus to yellowtail fingerings induced death with deformity similar to those observed in spontaneously diseased fish at 20-degrees-C but not at 26-degrees-C. The virus was reisolated from all the dead fish exper imentally infected. These results indicate that this virus is the caus ative agent of the death with deformity of yellowtail fingering.