中文摘要：

本试验旨在探讨2个生长阶段（幼鱼和养成阶段）斜带石斑鱼对饲料中脂肪的需要量。以鱼油调整饲料脂肪水平，配制5种脂肪水平（7.07%、9.92%、12.92%、15.95%和19.04%）的等氮饲料，分别投喂体重为9.1 g（幼鱼阶段）的斜带石斑鱼8周和体重为102.6 g（养成阶段）的斜带石斑鱼10周。同一生长阶段，每种饲料设3个重复，每个重复幼鱼阶段放养25尾鱼，养成阶段放养20尾鱼。结果表明：1）随着饲料脂肪水平的升高，幼鱼和养成阶段石斑鱼的增重率（ WGR）、特定生长率（ SGR）、蛋白质效率（ PER）、肥满度（ CF）和脏体比（ VSI）均随着饲料脂肪水平的升高呈先上升后下降趋势，饲料系数（ FCR）则呈相反的变化趋势，上述指标均在饲料脂肪水平为12.92%时获得极值。2）随着饲料脂肪水平的升高，幼鱼和养成阶段石斑鱼的全鱼粗蛋白质含量逐渐下降，全鱼和肌肉粗脂肪含量逐渐上升，全鱼和肌肉水分含量无显著变化（P〉0.05），全鱼和肌肉其他常规营养成分含量无规律性变化。3）随着饲料脂肪水平的升高，幼鱼和养成阶段石斑鱼的血浆总蛋白（ TP）和低密度脂蛋白（ LDLC）含量呈逐渐下降趋势，血浆高密度脂蛋白（ HDLC）含量呈逐渐升高趋势。幼鱼和养成阶段石斑鱼的血浆甘油三酯（ TG）和总胆固醇（ CHOL）含量与饲料脂肪水平呈线性或曲线关系。4）随着饲料脂肪水平的升高，幼鱼和养成阶段石斑鱼的肝脏肝脂酶（ HL）、脂蛋白脂酶（ LPL）、苹果酸脱氢酶（ MDH）活性均逐渐下降，而肝脏乳酸脱氢酶（ LDH）活性则逐渐上升。5）随着饲料脂肪水平的升高，幼鱼阶段肝脏酸性磷酸酶（ ACP）活性无显著变化（ P〉0.05），养成阶段肝脏ACP活性逐渐下降，幼鱼和养成阶段肝脏超氧化物歧化酶（ SOD）活性先升高后降低。幼鱼和养成阶段石斑鱼肝脏碱性磷?

英文摘要：

The present study was performed to investigate the dietary lipid requirements of grouper in two growth stages （ juvenile and grow out stages） . Five isonitrogenous diets were formulated with five lipid levels （7.07%, 9.92%, 12.92%, 15.95% and 19.04%）, which were regulated by fish oil. Fish with the body weight of 9.1 g （juvenile stage） were fed the 5 diets for 8 weeks, and fish with the body weight of 102.6 g （ grow out stage） were fed the 5 diets for 10 weeks. In the same growth stage, each diet had 3 replicates, and each replicate in juvenile and grow out stages had 25 and 20 fish, respectively. The results showed as follows：1） with the dietary lipid level increasing, the weight gain rate （ WGR） , specific growth rate （ SGR） , protein efficiency rate （ PER） , condition factor （ CF） and viscerasomatic index （ VSI） of fish in juvenile and grow out stages were firstly increased and then decreased, while the feed conversion ratio （ FCR） showed an opposite trend, and all of them obtained the extreme when dietary lipid level was 12.92%. 2） With the dietary lipid level increasing, the content of crude protein in whole body of fish in juvenile and grow out stages was gradually decreased, the content of crude lipid in whole body and muscle was gradually increased, and the content of moisture in whole body and muscle had no significant difference （ P〉0.05） , while the other indices in whole body and muscle had no regular changes. 3） With the dietary lipid level increasing, the contents of plasma total protein （ TP） and low density lipoprotein （ LDLC） of fish in juvenile and grow out stages were gradually decreased, while the content of plasma high density lipoprotein （ HDLC） was gradually increased. The contents of plasma triglyceride （ TG） and total cholesterol （ CHOL） of fish in juvenile and grow out stages had linear or curvilinear relationships with dietary lipid level, repectively. 4） With the dietary lipid level increasing, the activities o