日粮添加多不饱和脂肪酸对肉仔鸡抗氧化指标的影响

本试验通过观察日粮中添加多不饱和脂肪酸(PUFA)与肉仔鸡抗氧化酶活性及过氧化产物的量的关系,研究PUFA对肉仔鸡抗氧化能力的影响.试验包括3个单因子试验,3个处理组日粮为玉米豆粕型日粮,分别添加4.5%的禽脂、玉米油和鱼油,每个处理组6个重复,每个重复10只鸡.21日龄和42日龄分别检测脾脏、肠道抗氧化酶(谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT))活性和脂质过氧化产物(丙二醛,MDA)水平.综合本试验检测的抗氧化指标(GSH-Px、SOD、CAT和MDA)可知,日粮中添加鱼油和玉米油的肉仔鸡抗氧化酶活性较对照组均有不同程度的提高,而机体脂质过氧化产物(MDA)与对照组比较无显著性差异.这表明虽然添加PUFA易使机体发生过氧化反应,但由于机体抗氧化酶系(GSH-Px、SOD、CAT)功能的增强,可以抵消PUFA过氧化的不良作用.但是肉仔鸡抗氧化酶系功能的增强可能是PUFA具有直接调控机体抗氧化酶的作用,也可能是机体过氧化产物的反馈作用导致其功能代偿性增强.添加PUFA,脾脏CAT和SOD增强主要发生在21日龄;肠道CAT和SOD活性增强则主要发生在42日龄.由此可知,日粮中添加PUFA对肉仔鸡抗氧化酶活性的影响因生长阶段不同而存在组织器官特异性.

Effects of Dietary Polyunsaturated Fatty Acids on Antioxidant Indices in Broiler Chicks

This study was conducted to investigate the effects of dietary PUFA on antioxidant indices in chickens.One hundred and eighty 1-day-old male Arbor Acres chicks were randomly assigned to three groups of 60 chicks each,with 6 replicates of 10 chicks in each replicate.Three corn-soybean diets were supplemented with 45 g/kg of poultry oil,corn oil and fish oil,respectively,from 1 to 42 days of age.At d 21 and d 42,the activities of GSH-Px,SOD and CAT and levels of MDA were measured.Compared with control group,fish oil or corn oil enhanced the activities of GSH-Px,SOD and CAT in spleen or intestinal mucosa.And the levels of MDA which was peroxidatic metabolite of lipids in spleen or intestinal mucosa,were not significantly different from control group.The results showed that the enhancement of activities of antioxidant enzymes contributed to counteracting side-effect of lipid peroxidation.The mechanism,which PUFA increased the antioxidant status in chicks,was possibly the feedback of lipid peroxidation or the direct effects of fish oil and corn oil.In the present study,compared to control group,the activities of CAT and SOD of spleen were significantly increased at 21 d both in fish oil and corn oil group,while those of intestinal mucosa mainly increased at 42 d.These results showed that the effects of PUFA on antioxidant function in different stage were organ-specific.It is proposed that antioxidant function of spleen and intestinal mucosa,which was regulated by fish oil or corn oil,should be harmonized.