饲粮生物素水平对团头鲂幼鱼肠道消化酶活性、胴体组成及肝脏抗氧化能力的影响

摘要

选择初重为2.01±0.01 g团头鲂幼鱼720尾，分别饲喂生物素添加量为0，0.02，0.05，0.16，0.62和2.49 mg・kg-1等氮等能的纯化饲料，研究饲料中添加生物素对团头鲂幼鱼肠道消化酶活力、胴体组成及肝脏抗氧化的影响。结果表明：团头鲂幼鱼肠道脂肪酶和蛋白酶活力随生物素含量的升高呈现先增加后下降的变化，它们分别在生物素含量为0.62和0.16 mg・kg-1时达到最大值。饲料生物素含量为0.16 mg・kg-1组的团头鲂幼鱼与对照组相比具有较低的水分和较高的粗脂肪、粗蛋白含量，差异显著（P＜0.05）。饲料中生物素含量从0上升至0.05 mg・kg-1时，GSH含量，GSH-Px、SOD活性显著升高，差异显著（ P＜0.05）；当其含量进一步升高至2.49 mg・kg-1时，三者均无显著变化（P＞0.05）。综上所述，饲料中添加适宜浓度生物素可以提高团头鲂幼鱼肠道脂肪、蛋白质的消化能力，胴体粗脂肪和粗蛋白含量及肝脏抗氧化能力。%An 8-week feeding trial was conducted to investigate the effects of dietary biotin on intestinal digestible enzymes activities, carcass composition and hepatic antioxidant capability for juvenile blunt snout bream (Megalobrama amblycephala).Quadruple groups of fish (initial average weight 2.01 ±0.01g) were fed thrice daily with six isonitrogenous and isoenergetic purified diets containing 0 (basal diet), 0.02, 0.05, 0.16, 0.62 and 2.49 mg・kg-1 biotin, respectively.Results showed that intestinal lipase and protease activities increased initially and then decreased slightly with the dietary biotin levels increased from 0 to 2.49 mg・kg-1 , the maxima reached at 0.62 and 0.16 mg・kg-1 , respectively.Fish fed with the diet with biotin 0.16 mg・kg-1 had lower carcass moisture content and higher carcass crude lipid and crude protein contents than those fed with the basal diets , the differences were significant ( P <0.05).GSH, GSH-Px and SOD increased significantly ( P <0.05) as dietary biotin levels increased from 0 to 0.05 mg・kg-1 and then had plateaued.Results indicated that appropriate dietary biotin can improve intestinal lipase and protease activities , carcass lipid and crude protein content and hepatic antioxidant capacity of juvenile blunt snout bream .