作 者：
翟浩云;张璐;蔡亲晓;周智愚;殷浩然;耿丽娜;吴小易
关键词：
虎龙杂交斑;维生素E;生长;抗氧化;免疫
摘 要：
为研究虎龙杂交斑对维生素E(VE)的最适需求量,评估VE对虎龙杂交斑生长性能、抗氧化和免疫功能的影响,实验设计了 6 组VE 含量分别为 4.1、26.3、40.7、57.1、116.8、209.6 mg/kg的等能(340 kcal/100 g干物质)、等蛋白(占饲料干重的 51.5%)、等脂(占饲料干重的 9%)的实验饲料,每组 3 个平行.实验鱼初始均重为(14.22±0.01)g,养殖实验期间每日饱食投喂 2 次(8:00 和 16:30),周期为 8 周.生长实验结束后每组随机挑选 7 尾实验鱼进行 72 h铜胁迫实验.实验结果显示,摄食 57.1 mg/kg VE饲料实验鱼增重率(WG)显著高于摄食 4.1 mg/kg VE饲料实验鱼,各实验组肥满度(CF)、肝体比(HSI)和肠系膜脂肪比(IPF)无显著差异.全鱼和肌肉水分、粗蛋白和粗脂肪含量在各VE处理组之间也无显著差异.摄食 209.6 mg/kg VE饲料实验鱼肝脏VE含量高于摄食 4.1 mg/kg VE饲料实验鱼.肝脏总抗氧化能力(T-AOC)、血清溶菌酶(LZM)活性和免疫球蛋白(IgM)活性均先升后降,4.1 mg/kg VE组以上指标均低于 57.1 mg/kg VE组.铜胁迫 72 h后,40.7、57.1 和 116.8 mg/kg VE组存活率均显著高于 4.1 mg/kg VE组.40.7 mg/kg VE组头肾核因子E2 相关因子2 基因(nrf2)的相对表达量高于 4.1、26.3 和 116.8 mg/kg VE组.以WG和T-AOC为评价指标,基于二次折线模型确定虎龙杂交斑饲料中VE的最适需求量分别为 62.92 mg/kg饲料和 86.25 mg/kg饲料.实验结果表明,饲料中添加适量的VE可提高虎龙杂交斑生长性能、抗氧化和免疫能力.
译 名：
Effects of dietary vitamin E on growth,anti-oxidation and immunity of hybrid grouper juveniles(Epinephelus fuscoguttatus♀×E.lanceolatus♂)
关键词：
hybrid grouper%vitamin E%growth%anti-oxidation%immunity
摘 要：
An eight-week feeding trial was carried out to evaluate the influence of vitamin E(VE)on the growth performance,antioxidation and immunity of hybrid grouper juveniles(Epinephelus fuscoguttatus ♀×E.lanceol-atus ♂).Six isoenergetic(340 kcal/100 g dry matter),isoproteinic(51.5%of dry matter)and isolipidic(9%of the dry matter)diets were formulated to contain graded levels of VE(4.1,26.3,40.7,57.1,116.8,209.6 mg/kg,dry matter basis).Triplicate groups of twelve fish[initial average weight of(14.22±0.01)g]were stocked into floating cages and offered their prescribed diet twice daily(8:00 and 16:30)to apparent satiation.After the growth experi-ment,the remained experimental fish from each group were used for a 72 h copper challenge.Results showed that fish fed 57.1 mg/kg VE exhibited higher weight gain percentage(WG)than fish fed 4.1 mg/kg VE.Whereas,condi-tion factor(CF),hepatosomatic index(HSI)intraperitoneal fat(IPF)values remained non-significant among all dietary groups.Whole-body and muscular compositions(moisture,protein and lipid)did not show significant dif-ferences among all dietary groups.Fish fed 209.6 mg/kg VE had higher hepatic VE concentration than fish fed 4.1 mg/kg VE.The total-antioxidant capacity(T-AOC)of liver,serum lysozyme(LZM)and immunoglobulin(IgM)concentrations were increased with the increasing VE levels,reaching a peak value at the 57.1 mg/kg level,and thereafter,it started to decrease as dietary VE level further increased.After the challenge,the survival rate of the experimental fish fed with 40.7,57.1 or 116.8 mg/kg VE diet was higher than that of the experimental fish fed with 4.1 mg/kg VE.The relative expression of nuclear factor E2-related factor 2(Nrf2)in head kidney of fish fed 4.1 mg/kg VE was lower than that of fish fed 40.7,57.1 or 116.8 mg/kg VE.Generally,the analysis of a quadratic broken line model based on WG and T-AOC indicated that the optimal dietary VE requirement of hybrid grouper juvenile was found to be 62.92 mg/kg and 86.25 mg/kg dry matter,respectively.
