넙치 Paralichthys olivaceus 대사율에 미치는 수온과 체중의 영향

Abstract

The effect of water temperature and body weight on oxygen consumption by the fasted olive flounder Paralichthys olivaceus was investigated in order to assess the metabolic rate of this species under different conditions. The oxygen consumption rate (OCR) was measured at three different water temperatures (15, 20 and 25oC) and two different body weights [9.1±1.2 g (mean±SD) for the juvenile group and 266.4±29.3 g for the immature group] at an interval of 5 minutes for 24 hours using a closed flow-through respirometer. For each treatment condition, three replicates were set up and 135 fish in the juvenile group and 18 fish in the immature group were used. The OCRs exhibited a linear increase described by OCR=−82.06+28.30T (r2=0.96, p<0.001) in the juvenile group and OCR=−52.52+14.73T (r2=0.97, p<0.001) in the immature group. The OCRs decreased with increasing body weights at a given water temperature (p<0.001). The metabolic rate was related to the body weight of the fish as a power function with a weight exponent of between 0.77 and 0.82. Q10 values ranged 1.67~2.28 when the temperature was between 15 and 20oC, 1.57~1.93 when the temperature was between 20 and 25oC, and 1.79~1.89 when the temperature was between 15 and 25oC. The energy expenditure by respiration increased with increasing water temperature and decreasing body weight (p<0.001). The mean energy loss rates at 15,20 and 25oC were 115.9, 149.8 and 208.2 kJ kg−1d−1in the juvenile groups and 53.8, 81.2 and 101.9 kJ kg−1d−1 in the immature groups.