1973 年 39 巻 5 号 p. 477-480
An IPN-like epizootic with high mortality occurred among Amago, Oncorhynchus rhodurus macrostomus, reared in a rainbow trout farm. The cumulative mortality was about 28%.
Histopathological examinations showed that intensive congestion, hemorrhage and necrosis in the kidneys were rather more evident than was necrosis in the pancreatic tissue.
Inoculants prepared from the diseased Amago fry showed the isolant to have a titer of about 108.5 TCID50/ml. Neutralization tests of the agent with IPN polyvalent antiserum indicated that the agent was an IPN virus. This is the first case of an IPN outbreak among Oncorhynchus reared in Japan.
Yamame reared in nearby ponds of the same farm showed no mortality and no agent could be isolated.