plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111elSSN : 2287-8815
Effects of Acute High Water Temperature Exposure on Survival, PhysiologicalResponses and Histological Alterations in Juvenile and AdultWhitespotted Conger Conger myriaster
한지도·김효원1·김나영·길현우·김소선·김수철·진영국*
국립수산과학원 남해수산연구소 양식산업과, 1국립수산과학원 양식연구과
Juvenile and adult whitespotted conger Conger myriaster were exposed to different water temperatures to assess survival, body weight changes, plasma cortisol concentrations, and histological alterations in the gill and liver tissues. The experimental water temperatures were maintained at control, 24, 27, and 30°C, and fish were exposed for 96 h. Juvenile survival rate was 70.8% at 30°C, whereas adult survival rates were 80 and 60% at 27 and 30°C, respectively. Adult fish exposed to 30°C exhibited significant reductions in body weight and increased plasma cortisol concentrations. Histological examination of the gills revealed increased blood flow within the lamellar capillaries at 27°C, whereas necrosis of lamellar epithelial cells and fusion of the secondary lamellar epithelium were observed at 30°C. In the liver, increased glycogen accumulation within the hepatocyte cytoplasm was observed at 27°C, whereas hepatocyte condensation, necrosis, and vacuolated lipid droplets were observed at 30°C. These findings indicate that both juvenile and adult whitespotted conger experience physiological stress at 27°C, whereas exposure to 30°C adversely affects survival. The results of this study provide crucial baseline data for the development of future aquaculture technologies for whitespotted conger.
Conger myriaster, High temperature, Survival rate, Cortisol, Histological change