Abstract An 8-week experimental trial was designed to explore the effects of dietary protein level (DPL) and salinity on the growth performance and physiological parameters of genetically improved farmed tilapia (GIFT) juveniles (Oreochromis niloticus). Six diets were formulated with different dietary protein levels (18.20%, 24.32%, 30.60%, 36.42%, 43.27% and 49.49%) and two salinity levels (0and 8‰) in a 6 × 2 factorial design. 720GIFT juveniles (initial weight 3.25 g) were distributed into 36 plastic tanks (180 L) and fed each of the diets four times daily to satiation. The results suggested that the growth performance was increased significantly with increasing DPLs up to a certain level (36.42%) in freshwater and brackish water. The whole-body lipid content of the fish decreased significantly with increasing salinity, while the protein content increased (P

中文翻译：

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养殖盐度改变了遗传改良养殖罗非鱼 (GIFT) (Oreochromis niloticus) 幼鱼的日粮蛋白质需求、全身成分和营养代谢相关基因的表达

摘要 一项为期 8 周的试验旨在探讨日粮蛋白质水平 (DPL) 和盐度对遗传改良养殖罗非鱼 (GIFT) 幼鱼 (Oreochromis niloticus) 生长性能和生理参数的影响。在 6 × 2 因子设计中，用不同的日粮蛋白质水平（18.20%、24.32%、30.60%、36.42%、43.27% 和 49.49%）和两种盐度水平（0 和 8‰）配制了六种日粮。将 720 只 GIFT 幼鱼（初始体重 3.25 克）分配到 36 个塑料罐（180 升）中，每天对每种饲料喂食四次至饱。结果表明，在淡水和微咸水中，随着 DPL 增加到一定水平（36.42%），生长性能显着提高。鱼的全身脂质含量随着盐度的增加而显着下降，