사육 수온 및 사료 공급율이 넙치의 성장 및 체조성에 미치는 영향

Abstract

A 3×2 factorial experiment was conducted to investigate effects of water temperature and feeding rate on growth and body composition of olive flounder. Triplicate groups of fish (initial body weight of 118 g) fed a extruded pellet (55% protein and 4708 ㎈/g) to satiation and at restricted feeding rates of 0.25 and 0.4% body weight per day (BW/d) at the different water temperatures (13 and 18℃) for 9 weeks. Weight gain increased significantly with increase in feeding rates at each temperature. Weight gain of fish fed to satiation was significantly higher at 18 than 13℃, whereas, that of fish fed at 0.25 and 0.4% BW/d were significantly or slightly lower at 18 than 13℃. Feed efficiency and protein efficiency ratio of fish fed to satiation were not significantly different between 13 and 18℃, but those of fish fed at 0.25 and 0.4% BW/d were significantly higher at 13 than 18℃. The major finding of this study is that satiation feeding is efficient for optimal growth and feed efficiency of grower oliver flounder (116-164 g) in suboptimal water temperatures. The maintenance feeding ration which is zero growth performance, were 0.30 and 0.41% BW/day at 13 and 18℃, respectively. In the restricted feeding regime, compromised growth of fish were worsen in higher water temperature (18℃ vs. 13℃). It might be related to high metabolic rate of fish that spend more energy for maintenance metabolism. Based on these results, we suggest that a satiation feeding regime is recommended for a productive growth of grower olive flounder in the suboptimal temperature.