外源性金属硫蛋白对奶牛泌乳性能和抗氧化指标的影响

In order to approach the effects of exogenous metallothionein(Zn-MT) on milkability and anti-oxidative status in dairy cattle,an experiment was conducted with 24 lactating cows from Chinese Holstein which were randomly allocated to group A,groupB, group C and group D,and supplemented Zn-MT 0 mg.capita-1,4.0 mg.capita-1,8.0 mg.capita-1 and 12.0mg.capita-1 by intravenous injection respectively.The results showed that milk yields of the cows in group C and group D were higher（P﹤0.05）than those in group A,while there were no significant differences(P> 0.05) in milk yields between group B and group A and in milkfat percentages amang different groups. Blood GSH-Px activities of the cows in group B, group C and group D were also higher（P﹤0.05）than those in group A. Blood CAT activities of the cows in group D was greater than those in group B（P﹤0.05）and group A（P﹤0.01） respectively, and there was a significant difference (P﹤0.05) in blood CAT activities of the cows between group C and group A. T-AOC levels of the cows in group C and group D were also higher（P﹤0.05）than those in group A and group B. MDA contents in serum of the cows in group B, group C and group D were lower（P﹤0.05）than those in group A.The experimental results suggested that exogenous Zn-MT should be an effective anti-oxidative substance and physiologic accommodation composition for dairy cattle.