Viral diseases occurring in olive flounder hatchery in Korea

摘要

In order to elucidate the state of disease, especially viral diseases, and to prevent viral diseases from occurring in Oliver flounder hatcheries, a range of studies, including epidemiological study, had been performed from 1997 to 2003. The location of the hatcheries investigated were included several representative east (Kangnung, Uljin, Pohang, Yangsan, Ulsan, Busan), south (Wando, Changheung, Goheung, Yeosu, Namhae, Tongyeong, Geoje, Jeju) and west (Seosan, Kunsan, Gochang, Yeongkwang, Mokpo, Chindo) costal area in Korea peninsula. A total of 2000 cases were examined for 7 years, among them, mortality caused by viral agents were occupied 22% equivalent to 446 cases. Mortalities associated with viral infection were considerably increased from 14% in 1997 to 27% in 2003. A variety of viral diseases were observed, and the occurrence of viral epidermal hyperplasia, viral ascites & viral deformity, viral nervous necrosis, and hirame rhabdoviral disease was 14%, 51%, 25%, and 8%, respectively. As a result of investigating viral infection of broodstock flounder, the infection rate of MABV in hatcheries was identified approximately 30%, therefore, it is highly necessary to acquire and keep non-infected broodstock fishes.