저수온 노출에 따른 돌돔(Oplegnathus fasciantus)과 민들조개(Gomphina melanaegis)의 생리활성 변화 연구

Abstract

Physiological response of fish and bivalve was estimated to identify the physiological changes of test species by lowering water temperature due to the abrupt stop of cooling water discharge from power plant. The experiment was conducted by two conditions; fall and winter by decreasing water temperature (2°C /2 days) from 26°C to 17°C for fall scenario and from 15°C to 9°C for winter scenario, respectively. Test organisms were parrot fish (Oplegnathus fasciantus) and bivalve (Gomphina melanaegis), and end points were mortality for both species, hematocrit and cortisol for fish, and hemolymph and superoxide dismutase(SOD) for bivalve. 48/96hr mortality test revealed no mortality for fish and 47% mortality for bivalve at 96hr/ 26°C only. Significant increases of hematocrit and cortisol were found at fishes exposed to 26°C (high temperature) and lower temperature (9∼13°C), respectively. Hemolymph and SOD for bivalve tended to decrease by lowering water temperature from 15 to 9°C (winter scenario) and no changes from 26 to 17°C (fall scenario). Fall scenario (from 15 to 9°C) showed more significant changes of physiological response than winter cases (26 to 17°C).