许氏平鲉幼鱼的赖氨酸需求量

通过8周的生长实验确定了许氏平(Sebastes schlegeli)幼鱼的赖氨酸需求量。饲料必需氨基酸组成(除赖氨酸外)参照鱼体肌肉蛋白的氨基酸模式,配制赖氨酸含量为1.542、.04、2.54、3.04、3.54和4.04%的等氮等能的六种半精制饲料。研究结果表明,随着饲料中赖氨酸含量的增加,增重率逐渐提高,当饲料中赖氨酸含量为3.54%时,达到最大值(P0.05)。基础饲料组的蛋白质贮积率最低,且显著低于3.54%组(P0.05),和其他组之间差异不显著(P0.05)。随着饲料中赖氨酸含量的增加,饲料系数逐渐降低,当饲料中赖氨酸含量为3.54%时达最小值,随着饲料中赖氨酸含量继续增加饲料系数呈上升趋势(P0.05)。饲料中赖氨酸水平对鱼体的干物质、蛋白质、脂肪、灰分和能量含量均无显著影响(P0.05)。饲料中赖氨酸水平对血清谷丙转氨酶(ALT)、谷草转氨酶(AST)活性有显著性影响(P0.05),而对血清甘油三酯及胆固醇含量没有显著性影响(P0.05)。通过回归分析,得出许氏平幼鱼最大生长的饲料赖氨酸需求量2.99%,占饲料蛋白的6.16%。  

Quantitative dietary lysine requirement for juvenile Sebastes schlegeli

A 82week growth trial was conducted to determine the quantitative dietary lysine requirement for juvenile Sebastes schlegeli.Semipurified diets were formulated to be isonitrogenous and isoenergetic (48.50% crude protein and 18.04kJ/g gross energy).Crystalline Lamino acids were use to provide part of dietary protein.The amino acid pattern except lysine of the muscle protein of Sebastes schlegeli was used as reference.Six diets were formulated to contain 15.4, 20.4, 25.4, 30.4, 35.4 or 40.4g lysine kg-1 dry matter.The experiment was conducted in triplicates in 8421 indoor flow-through circular conical tanks at 19.5 ±0.5 ℃and 30 ‰-34 ‰ salinity.The results showed that dietary lysine level significantly affected weight gain (WG), food conversion ratio (FCR), protein retention efficiency (PRE-and activity of serum glutamic2oxalacetic transaminase (AST-and glutamic2pyruvic transaminase (ALT).With increase in dietary lysine level, weight gain increased while highest value was observed at 3.54% dietary lysine level.Protein retention efficiency was lower in the fish fed the basal diet ( P 0.05-was found in feeding rate ( FR), energy retention efficiency ( ERE), hepatosomatic index (HSI), content of serum triglyceride and cholesterol, body composition of protein, lipid, ash, dry matter and energy.By regression, the optimal dietary lysine requirement for maximum growth of Sebastes schlegeli was 2.99% of dry matter of 6.16% of protein.