摘要
本文旨在研究团头鲂幼鱼日粮中亚麻酸的适宜需求量。配制了六组亚麻酸含量分别为0,5,10,15,20和25 g kg-1的等氮等能饲料,饲养平均体重为27.45±0.11 g的团头鲂幼鱼,实验周期为9周。结果表明:(1)饲料中亚麻酸水平对存活率无显著影响;随着饲料亚麻酸水平的增加,鱼体末重、特定生长率(SGR)和饲料效率(FER)显著升高,均在20 g kg-1组达到最大,随着亚麻酸水平进一步增加,上述指标显著降低。(2)随着饲料亚麻酸水平的增加,肌肉亚麻酸含量和n-3多不饱和脂肪酸含量呈升高的趋势,但总饱和脂肪酸含量逐渐降低。(3)与对照组相比,20 g kg-1实验组的血清碱性磷酸酶(ALP)、总蛋白(TP)、白蛋白(ALB)含量和白细胞数量(WBC)最高,同时,20g kg-1实验组的总甘油三酯显著高于对照组。血糖含量随饲料亚麻酸含量的增加而显著升高。(4)团头鲂肝脏超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GPX)活性随饲料亚麻酸水平的升高而显著升高,超过15 g kg-1以后趋于平缓。以鱼体SGR和FER为评价指标,经曲线回归分析,发现日粮中亚麻酸水平分别在17.5 g kg-1和15.6 g kg-1的团头鲂幼鱼具有最佳的生长性能。
A nine–week feeding trial was performed to determine the dietary linolenic acid(LNA)requirements of juvenile blunt snout bream. Six iso–nitrogenous, semi–purified diets were prepared with different concentrations of LNA(0–25 g kg-1). Dietary LNA had no significant effects on survival rate. However, final fish weight, specific growth rate(SGR), and feed efficiency ratio(FER) increased with increasing dietary LNA concentrations up to 20 g kg-1.Dietary LNA increased muscle LNA and total n–3 PUFA contents, but decreased total saturated fatty acid content. Fish fed 20 g kg-1 LNA had the highest plasma alkaline phosphatase, total protein, albumin, and white blood cell count levels. Additionally, fish fed 20 g kg-1 LNA had higher triglyceride levels than control fish.
引文
