The optimum water temperature required for the normal growth of Nile tilapia is 25–30°C. In this study, tilapia was reared under suboptimal temperature (21.50 ± 1.50°C) and fed four diets with fish oil (FO), corn oil (CO), sunflower oil (SFO) and linseed oil (LnO) for 8 weeks. The results revealed improved final weight, average daily gain and intestinal amylase activity in the LnO group compared to FO and SFO groups (p < .05). The feed intake was increased significantly in FO and LnO groups compared to CO and SFO groups, while the feed conversion ratio was increased in the FO group (p < .05). The CO, SFO and LnO diets resulted in higher carcass lipids than fish fed FO, while CO decreased the ash content (p < .05). The growth hormone was significantly lowered by LnO, followed by SFO, while CO improved the serum alkaline phosphatase activity (p < .05). Glutathione peroxidase enhanced in fish fed SFO, while the lowest activities were recorded in fish fed FO (p < .05). Total superoxide dismutase was significantly elevated by CO and LnO when compared with fish fed FO and SFO (p < .05). Substituting FO with vegetable oils had normal intestinal and liver histological appearance. It could be concluded that substituting FO with either CO or LnO for Nile tilapia could maintain the normal growth performance and feed utilization with enhanced antioxidant capacity under suboptimal temperature.

中文翻译：

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尼罗罗非鱼（Oreochromis niloticus）在最适温度下使用植物油源的总体性能

尼罗罗非鱼正常生长所需的最佳水温为25–30°C。在这项研究中，罗非鱼在最适温度（21.50±1.50°C）下饲养，并以鱼油（FO），玉米油（CO），向日葵油（SFO）和亚麻籽油（LnO）的四种饮食喂养了8周。结果显示，与FO和SFO组相比，LnO组的最终体重，平均日增重和肠道淀粉酶活性有所改善（p  <.05）。与CO和SFO组相比，FO和LnO组的采食量显着增加，而FO组的采食转化率增加（p  <.05）。CO，SFO和LnO日粮比饲喂鱼的FO导致car体脂质更高，而CO降低了灰分（p <.05）。LnO显着降低了生长激素，随后SFO显着降低了生长激素，而CO改善了血清碱性磷酸酶活性（p  <.05）。喂食SFO的鱼体内谷胱甘肽过氧化物酶增强，而喂食FO的谷胱甘肽过氧化物酶最低（p  <.05）。与喂食FO和SFO的鱼相比，CO和LnO显着提高了总超氧化物歧化酶含量（p  <.05）。用植物油代替FO具有正常的肠道和肝脏组织学外观。可以得出结论，在次适温度下，用CO或LnO代替FO代替尼罗罗非鱼可以维持正常的生长性能和饲料利用率，并具有增强的抗氧化能力。