饲料中碳水化合物水平对鲈鱼生长、生理状态参数及体组成的影响

Effects of dietary carbohydrate level on growth performance, physiological status and body composition of Japanese seabass Lateolabrax japonicus

中文关键词: 鲈鱼  碳水化合物  生长  血糖  糖原

英文关键词: Japanese seabass  Carbohydrate  Growth  Blood glucose  Glycogen

中文摘要:

      以初始体重34.26±0.37g的鲈鱼（Lateolabrax japonicus）为实验研究对象，进行为期10周的生长实验，探讨饲料中不同的碳水化合物（CHO）水平对其生长、饲料利用、血糖水平和糖酵解酶活力的影响。实验配制6种不同碳水化合物水平（0、6、12、18、24和30%）的等氮等脂饲料。结果表明：随着饲料中碳水化合物水平的升高，特定生长率（SGR）和饲料效率（FE）均呈现先上升后下降的趋势，都在12%组达到最大值，并显著高于24%和30%组（P﹤0.05），而肝体比（HSI）和脏体比（VSI）呈显著升高的趋势（P﹤0.05），且在30%组达到最大值。饲料中不同碳水化合物水平对鲈鱼存活率、肥满度、肌糖原和己糖激酶（HK）活力均无显著影响（P﹥0.05）。饲料中不同碳水化合物水平显著提高了鲈鱼粗蛋白和粗脂肪含量（P﹤0.05），降低了灰分含量（P﹤0.05）。饲料干物质的表观消化率（ADC）在各组之间差异显著（P＜0.05），18%组显著高于其余5组（P﹤0.05），12%组饲料蛋白质的表观消化率显著高于对照组（P﹤0.05）。血清中葡萄糖、甘油三酯、胆固醇含量随着饲料中碳水化合物水平的增加而逐渐上升（P﹤0.05），肝糖原含量先显著升高后趋于平稳（P﹤0.05）。以特定生长率（SGR）为评价指标，用二次曲线模型分析得出鲈鱼饲料中碳水化合物的适宜添加量约为17.75%。

英文摘要:

      A 10-week feeding trial was conducted to evaluate the effects of dietary carbohydrate level on growth performance, feed utilization, plasma glucose and glycolytic enzyme activities of Japanese seabass, Lateolabrax japonicus. Six isonitrogenous and isolopidic practical diets were formulated to contain graded levels of carbohydrate (0, 6%,12%,18%,24% and 30%). Specific growth rate (SGR) and feed efficiency(FE) significantly increased first and then decreased with the increasing of dietary carbohydrate (P﹤0.05), and reached the highest at the CHO level of 12%, which were significantly higher than that of 24% and 30% group(P﹤0.05). The hepatopancreas somatic index(HSI) and viscerosomatic index(VSI) increased significantly with the increasing dietary carbohydrate contents(P﹤0.05). No significant differences were observed in survival,condition factor(CF),muscle glycogen and hexokinase (HK) among different levels of Carbohydrate (P>0.05).Dietary CHO significantly improved the content of crude protein and crude lipid(P﹤0.05), but significantly decreased ash of Japanese seabass(P﹤0.05).The apparent digestibility coefficients (ADC) of dry matter and crude protein in diets reached the highest at the starch level of 18% and 12% respectively, which were significantly higher than that of the control group (P﹤0.05). With increasing dietary carbohydrate, serum glucose, plasma triglyceride and plasma total cholesterol significantly increased (P﹤0.05). The liver glycogen increased first and then leveled off with the increasing carbohydrate level(P﹤0.05). On the basis of SGR, the optimum dietary carbohydrate level for the growth of Japanese seabass was estimated using second-order polynomial regression analysis to be 17.75%.