氧化鱼油对草鱼幼鱼脂质过氧化及抗氧化酶活性的影响

[目的] 旨在研究氧化鱼油对草鱼(Ctenopharyngodon idellus)幼鱼脂质过氧化及抗氧化酶活性的影响。[方法] 将204尾草鱼幼鱼随机分成4个处理组,每个处理3个重复,每个重复17尾鱼。分别以新鲜鱼油[过氧化值(POV):9.07 mmol？kg-1]与氧化鱼油(POV:49.72、144.64和345.45 mmol？kg-1)为脂肪源制成4种等氮(粗蛋白含量31%)等能(16 MJ？kg-1)的配合饲料,投喂平均体质量(30.0±2.6)g的草鱼幼鱼8周。[结果] 与新鲜鱼油组相比,POV为345.45 mmol？kg-1的氧化鱼油处理组试验鱼血清、肝胰脏、肾脏、肠道组织丙二醛(MDA)含量显著升高(P<0.05);血清、肝胰脏、肾脏、肌肉、肠道组织中总抗氧化能力(T-AOC)显著下降(P<0.05);血清、肝胰脏、肾脏、肌肉超氧化物歧化酶(SOD)活性显著下降(P<0.05);血清、肝胰脏、肌肉组织中过氧化氢酶(CAT)活性显著下降(P<0.05);各组织中谷胱甘肽过氧化物酶(GSH-PX)活性无显著变化(P>0.05);草鱼幼鱼不同组织中各抗氧化酶活性从大到小分布:SOD活性:血清、肝胰脏、肾脏、肌肉,CAT活性:肝胰脏、肾脏、血清、肠道、肌肉,GSH-PX活性:肝胰脏、血清、肾脏、肠道;MDA含量从高到低依次为:血清、肠道、肌肉、肝胰脏、肾脏;T-AOC含量从高到低依次为:肝胰脏、血清、肠道、肾脏、肌肉。[结论] 氧化鱼油能引起草鱼幼鱼脂质过氧化,降低组织中主要抗氧化酶活性,诱导氧化应激;鱼类不同组织抗氧化酶活性和丙二醛含量存在一定差异性,肝胰脏中抗氧化酶活性较高且对氧化鱼油诱导的氧化应激比较敏感。
[Objectives] The study was conducted to investigate the effects of oxidized fish oil on lipid peroxidation and antioxidant enzyme activities of juvenile grass carp(Ctenopharyngodon idellus). [Methods] An 8-week feeding trial on juveniles(average weight of 30.0 g)was conducted in quadruplicate groups, 3 replicates in per group, and 17 juvenile grass carp in each replicate. Four isonitrogenous and isocaloric diets were formulated utilizing fresh fish oil[peroxide value(POV):9.07 mmol？kg-1]and oxidized fish oil(POV:49.72, 144.64, 345.45 mmol？kg-1)as the lipid source respectively, and the diet prepared with fresh fish oil served as control. [Results] Oxidized fish oil increased the content of MDA in the body tissues, and decreased the activities of antioxidant enzymes. Compared to the control, fish in P3 group(POV:345.45 mmol？kg-1), the levels of MDA in serum, liver, kidney, intestine increased significantly(P<0.05), the levels of T-AOC in serum, liver, kidney, muscle, intestine decreased significantly(P<0.05), and the activity of SOD in serum, liver, kidney, muscle, CAT in serum, liver, muscle decreased significantly(P<0.05). However, the activity of GSH-PX showed no differences(P>0.05). The activity of main antioxidant enzymes was distributed as follows, SOD:serum, liver, kidney, muscle;CAT:liver, kidney, serum, intestine, muscle;GSH-PX:liver, serum, kidney, intestine. The content of MDA and T-AOC distributed as follows, MDA:serum, intestine, muscle, liver, kidney;T-AOC:liver, serum, intestine, kidney, muscle. [Conclusions] Oxidized fish oil could increase the level of MDA, decrease the ability of antioxidant, and induce oxidative stress of juvenile grass carp. There was a tissue-specific of antioxidant enzyme activity and MDA content in different tissues of juvenile grass carp. The antioxidant enzymes in