高蛋白和高脂肪饲料对二倍体与三倍体山女鳟生长性能和营养成分的影响

以二倍体山女鳟Oncorhynchus masou（初重为113.53 g±1.65 g）和三倍体山女鳟（初重为115.49 g±1.66 g）为对象,研究了饲喂高蛋白和高脂肪饲料对山女鳟生长性能和生化成分的影响。试验设二倍体普通饲料组（G1）、高脂肪饲料组（G2）、高蛋白饲料组（G3）以及三倍体普通饲料组（G4）、高脂肪饲料组（G5）和高蛋白饲料组（G6）,每个处理设3个重复,每个重复放30尾鱼。试验期间,水温为10.5～16.7℃,pH为7.2～7.5,溶氧〉6.0 mg/L,试验共进行140 d。结果表明：各处理组山女鳟的增重率、特定生长率、成活率和肥满度均无显著差异（P〉0.05）;二倍体对照组（G1）与三倍体对照组（G4）鱼肌肉中的粗脂肪、粗灰分和初水分无显著差异（P〉0.05）;各处理组鱼肌肉中的粗蛋白含量均无显著差异（P〉0.05）;二倍体高脂肪饲料组鱼肌肉中的粗脂肪水平显著高于其对照组（P〈0.05）,三倍体高脂肪饲料组鱼肌肉中的粗脂肪水平显著高于其对照组（P〈0.05）;各处理组鱼肌肉中的氨基酸组成及各种氨基酸含量均无显著差异（P〉0.05）;但二倍体高蛋白饲料组鱼的必需氨基酸含量和必需氨基酸指数显著高于其对照组（P〈0.05）,三倍体高蛋白饲料组的必需氨基酸含量和必需氨基酸指数显著高于其高脂肪饲料组（P〈0.05）。与二倍体山女鳟相比,三倍体山女鳟其生长和营养成分并不好于二倍体鱼;投喂高蛋白饲料增加了二倍体山女鳟肌肉中的必需氨基酸含量,但未显著提高三倍体鱼的必需氨基酸含量;饲喂高脂肪饲料可提高二倍体和三倍体鱼肌肉中的脂肪水平。

Effects of diets containing different protein and lipid levels on growth performances and body composition in diploid and triploid Pacific salmon Oncorhynchus masou

The effects of diets containing different protein and lipid levels on growth performances and body composition in diploid and triploid Pacific salmon Oncorhynchus masou with initial body weight（diploid 113.53 g±1.65 g and triploid 115.49 g±1.66 g） were studied at water temperature fluctuated from 10.5 ℃ to 16.7℃,pH value from 7.2 to 7.5,and the dissolved oxygen of above 6.0 mg/L for 140 days.No significant differences in weight gain,specific growth rate,survival rate and condition factor were found between the diploid and triploid（P〉0.05） fish fed the higher protein and lipid diets,without differences from the fish in the control groups（P〉0.05）.There were no differences in crude protein,crude lipid,crude ash and moisture levels in the muscle between diploid and triploid（P〉0.05）.The fish fed the diets containing higher protein and lipid had not change in muscular crude protein levels compared with the fish in the control groups（P〉0.05）.However,there were significant higher muscular crude lipid levels in the fish fed the higher lipid diets than those in the fish fed the control diets（P〉0.05）.No changes in amino acid composition was observed between the diploid and triploid（P〉0.05）fish,and in the fish fed the higher protein and lipid diets（P〈0.05）.However,the essential amino acid content and essential amino acid index were found higher in the fish fed the higher protein diets compared with the fish in the control groups（P〈0.05）.In conclusion,the diploid and triploid had the similar growth performance and body composition,and increase in the essential amino acid content in muscles when they fed higher protein diets,and increase in the crude lipid in muscle when they fed higher lipid diets.