2019 年 54 巻 1 号 p. 16-19
Outbreaks of suspected viral nervous necrosis emerged in cultured groupers in Guangxi, China in August 2018. Histopathology showed severe vacuolation in the brain tissue of the diseased juvenile hybrid grouper (Epinephelus fuscoguttatus♀ × Epinephelus lanceolatus♂). A nervous necrosis virus (NNV) was isolated from pooled sample of the brain and eyes using a grouper cell line EAGB. Cytopathic effect with multiple cytoplasmic vacuolation cells developed in EAGB cells. The coat protein gene sequence of the isolate (GNNV-Gx) showed that it belonged to RGNNV genotype and was most closely related to that of a tiger grouper NNV registered in GenBank. The infectivity of the isolate decreased remarkably at pH 3 and pH 10 and was susceptible to 60°C.
