해산어류의 담수순화 양식을 위한 기초자료를 얻고자, 감성돔을 재료로 하여 담수와 해수에서 90일간 사육하였을 때, 어체의 생리상태를 스트레스, 삼투압조절, 성장 및 생존율 측면에 서 조사 비교하였다. 스트레스 측면에서 담수돔과 해수돔의 혈장 cortisol농도의 경우 60일째까지 유의한 차이가 없었으며, 실험종료시에는 각각 12.6$pm$5.0 ng/ml, 4.5$pm$2.9 ng/ml로 담수돔이 해수돔보다 높았지만 안정시의 농노에 포함되는 것으로 나타났다. 삼투압조절 측면에서 담수돔과 해수돔의 삼투질농도의 범위는 각각 346.7$pm$4.6$~$356.5$pm$2.1 mOsm/kg, 350.0$pm$2.0$~$351.0$pm$2.6 mOsm/kg으로 차이가 나타나지 않았으며, 또한 아가미 조직의 손상이나 세포의 괴사도 관찰되지 않았다. 성장 및 생존율 측면에서 실험종료시 담수돔과 해수돔의 전장은 각각 17.0$pm$1.3 cm, 16.1$pm$0.8, 체중은 각각 88.2$pm$22.0 g, 69.4$pm$11.8 g, 생존율은 각각 $80.2\%$, $73.7\%$로 담수돔에서 높게 나타났으나 유의한 차이는 인정되지 않았다. 또한 증중률 등의 성장관련 요인과 체성분의 조성면에서도 담수돔과 해수돔간의 차이가 없는 것으로 나타났다.
This study was conducted to compare the physiological conditions of black porgy (Acanthopagrus schlegeli) when reared in freshwater (0 psu) and seawater (35 psu) during 90 days. In terms of stress response, there was no significant difference in cortisol levels of the fish reared either freshwater or seawater until 60 days. Although cortisol level of fish reared in freshwater(12.6$pm$5.0 ng/ml) was significantly higher than in seawater (4.5$pm$2.9 ng/ml) at the end of experiment, these values were stable levels as compared with that of non-stressed fish. No significant differences in plasma osmolalities were recognized between the fish reared in freshwater (346.7$pm$4.6$~$356.5$pm$2.1 mOsm/kg) and seawater (350.0$pm$2.0$~$357.0$pm$22.6 mOsm/kg). Normal structure of gill lamellae without histological damage or cell necrosis has been observed in the fish reared in freshwater. In connection with growth and survival rate, total length and body weight of fish reared in freshwater were slightly longer and higher than those of fish reared in seawater. Survival rate of black porgy reared in freshwater was slightly higher than that of fish reared in seawater, but there was no significant difference. The results suggest that black porgy is reared with normal growth rate in freshwater without stress.
