Abstract The n-3 LC-PUFAs requirement was evaluated for Totoaba macdonaldi. Four isonitrogenous and isolipidic diets were formulated to contain increasing levels of n-3 LC-PUFAs (0.4, 0.8, 1.0, and 1.4% of the dry diet) and fed to juvenile totoaba (1.5 g initial body weight and 47 mm initial total length) for 56 days. Growth, survival, fish whole body proximate composition, fatty acid profile, feed utilization, and condition factor were evaluated in triplicate groups. Growth in terms of final weight and total length of fish fed diets containing 1.0% n-3 LC-PUFAs resulted in significantly higher values (16.11 ± 0.38 g and 119.62 ± 1.81 mm, respectively) compared to other treatments. However, fish fed diets supplemented with 1.4% n-3 LC-PUFAs resulted in the lowest final weight and total length (12.34 ± 0.49 g and 110.13 ± 0.92 mm, respectively). There were no significant differences in percent survival (all treatments 100%) and condition factor among treatments. The recommended n-3 LC-PUFA level in the diet for juvenile totoaba to attain the highest growth, and survival, as estimated here for 1 g fish, is 0.92% n-3 LC-PUFAs of the diet. Additionally, feed utilization in terms of feed conversion rate was lower in fish fed the diet containing 1.0% n-3 LC-PUFAs compared with the other treatments (0.7 vs. 0.8, P

中文翻译：

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日粮 n-3 LC-PUFA 水平对石首鱼幼鱼生长、存活和饲料利用的影响

摘要 评估了 Totoaba macdonaldi 对 n-3 LC-PUFA 的要求。配制四种异氮和异脂日粮以含有增加水平的 n-3 LC-PUFA（干日粮的 0.4、0.8、1.0 和 1.4%），并饲喂幼鱼（1.5 g 初始体重和 47 mm 初始总长度） ) 56 天。生长、存活、鱼全身近似组成、脂肪酸谱、饲料利用率和条件因素以三份组进行评估。与其他处理相比，含有 1.0% n-3 LC-PUFA 的鱼饲料的最终重量和总长度的增长导致显着更高的值（分别为 16.11 ± 0.38 g 和 119.62 ± 1.81 mm）。然而，添加 1.4% n-3 LC-PUFA 的鱼饲料导致最低的最终重量和总长度（分别为 12.34 ± 0.49 g 和 110.13 ± 0.92 mm）。治疗之间的存活百分比（所有治疗均为 100%）和状况因素没有显着差异。幼鱼在饮食中推荐的 n-3 LC-PUFA 水平是达到最高生长和存活率，如这里对 1 克鱼的估计，是饮食中 n-3 LC-PUFA 的 0.92%。此外，与其他处理相比，饲喂含有 1.0% n-3 LC-PUFA 的饲料的鱼的饲料转化率的饲料利用率较低（0.7 对 0.8，P