本试验旨在研究纳米氧化锌对肉仔鸡抗氧化性能的影响。选用1日龄爱拔益加肉仔鸡192只，随机分为4个组，每个组4个重复，每个重复12只鸡。以添加硫酸锌（含锌80 mg/kg）的日粮为对照组，即A组，添加含锌40、80、120 mg/kg的3个纳米氧化锌水平组为试验组，即B、C、D组，试验期6周。试验结果表明：40 mg/kg锌添加水平的纳米氧化锌组能够显著提高（21、42 d）肉仔鸡血清中谷胱甘肽过氧化物酶（GSH-Px）活性（P<0.05、P<0.01），极显著提高（21、42 d）血清中总抗氧化能力（T-AOC）（P<0.01、P<0.01），减少（21 d）血清中一氧化氮（NO）生成（P<0.05）。80 mg/kg锌添加水平的纳米氧化锌组能够极显著提高（42 d）肉仔鸡血清中GSH-Px活性（P<0.01），显著提高（42 d）肝组织中过氧化氢酶（CAT）和TAOC活性（P<0.05、P<0.01），极显著提高（21 d）血清中TAOC（P<0.01），减少（21、42 d）血清中NO生成（P<0.05、P<0.01），并能提高（42 d）血清抑制羟自由基能力（P<0.05），提高（21 d）肝组织中抗超氧阴离子自由基活性（P<0.05）。由此可知，日粮添加纳米氧化锌可在一定程度上提高肉仔鸡机体的抗氧化性能，增强抗氧化酶活性，降低自由基的产生，以40、80 mg/kg添加量效果较佳。

The experiment was conducted to study the effects of nano-zinc oxide on antioxidant function in broilers. One hundred and ninetytwo Arbor Acres (AA) broilers at the age of one day old were randomly divided into 4 groups with 4 replicates in each group and 12 birds in each replicate. The zinc sulfate (zinc level of 80 mg/kg) supplemented in diet was the control group (group A). Zinc supplemental levels of 40, 80, 120 mg/kg were groups B, C and D, which were added as nanozinc oxide. The experiment lasted for 6 weeks. The results were as follows: supplemental Zn level of 40 mg/kg, the activity of GSH-Px in serum (21, 42 d) of broiler were significantly increased (P<0.05, P<0.01), the TAOC in serum (21, 42 d) were significantly increased (P<0.01, P<0.01), the content of MDA in serum (21 d) were reduced (P<0.05); Zn supplemental level of 80 mg/kg, the activity of GSH-Px (42 d) was significantly increased (P<0.01), the CAT and T-AOC in liver (42 d) were significantly increased (P<0.05, P<0.01), the activity of T-AOC in serum (21 d) was significantly increased (P<0.05), the content of NO in serum (21, 42 d) were reduced (P<0.05, P<0.01), and enhanced the ability of inhibiting hydroxyl radical (·OH) in serum (42 d) (P<0.05), also enhanced the activity of resisting superoxide anion free radical (O2-·) in liver (21 d) (P<0.05). The results showed that adding proteinbound zinc and nanozinc oxide to diet could enhance antioxidant function in broilers, strengthen the activities of antioxidases and reduce the levels of free radicals, in which supplemental nano-zinc oxide level of 40, 80 mg/kg were optimal levels.