밀폐순환 유수식 산소소비 측정장치를 이용하여 해수 및 담수에서 사육한 감성돔, Acanthopagrus schlegeli의 개체수에 따른 산소소비 경향을 조사하였다. 해수 및 담수순화된 평균체중 36.4 g의 감성돔을 각각 1마리와 3마리 그룹으로 나누어 수온(15, 20, $25^{circ}C$), 광주기(12L:12D)를 달리하여 실험하였다. 모든 실험조건에서 감성돔은 명기동안에 산소소비량이 많고, 암기동안에는 적은 뚜렷한 리듬을 보였으며, 수온상승과 비례하여 산소소비량이 증가하였다. 감성돔의 호흡수는 담수돔 보다 해수돔이 많았으며, 수온상승과 비례하여 증가하였다. 수온 15, 20, $25^{circ}C$에서 개체수가 1마리일 때 해수돔의 산소소비량은 각각 140.0, 174.8, 282.3 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$, 담수돔은 177.5, 307.8, 413.1 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$로 해수돔에 비해 담수돔의 산소소비량이 많았다. 그러나 개체수가 3마리일 때는 해수돔 각각 200.5, 274.7, 339.1 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$, 담수돔 177.5, 307.8, 413.1 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$로 담수돔 보다 해수돔의 산소소비량이 많았다.
Comparison of fish number on routine oxygen consumption (OC) of black porgy (Acanthopagrus schlegeli) reared in seawater (SW) versus freshwater (FW) was performed in closed water-recirculating system containing respiratory chamber. Fish acclimated in separate indoor tanks with SW or FW were sampled as two groups (one or three of fish used, $mean;{pm};S.D.=36.4{pm}9.8$). OC of fish reared in both SW and FW showed clear temporal rhythms, with higher values in the daytime and lower values at night, in accordance with light (09:00-21:00 h) and dark (21:00-09:00 h) phases of the diel cycle (12L:12D). The OC of the fish increased linearly with the water temperature. The OCs of black porgy reared in SW and FW at 15, 20, $25^{circ}C$ were 140.0, 174.8, 282.3 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$ and 177.5, 307.8, 413.1 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$ for the one of fish used, and 200.5, 274.7, 339.1 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$ and 118.2, 188.2, 252.8 mg $O^2{cdot}kg^{-1}{cdot}h^{-1}$ for three of fish used, respectively. Black porgy reared in SW had higher ventilation rates than those in FW. These results indicate that black porgy reared in FW had higher OC than those in SW at the one of fish used, but the fish reared in SW had higher OC than those in FW at the three of fish used.
