Abstract: Objective]The objective of the present study is to investigate the influence of castration on serum protein metabolism,energy metabolism and antioxidant index on Simmental cattle.[Method]50 healthy Simmental cattle (16 month)were used in a paired design of single factor by body weight.[Result]The results showed that the content of creatine kinase in the castrated group was lower than uncastrated group and there were significant difference(P<0.05).The contents of urea nitrogen and albumin in castrated group were higher than uncastrated group by 5.63;and 2.59;,respectively.The difference were extremely signif-icant (P<0.01).The ratio of albumin and globulin in the castrated group was significantly higher than un-castrated group(P<0.05 ).As for SOD,GSH -PX and MDA,there were no difference in the castrated group and uncastrated group (P>0.05).[Conclusion]The results suggested that the castration slows down the metabolic oxidation process,slows down,and steers become gentle and the relative reduction in the a-mount of activity,thus resulting in the body's demand for ATP.Serum creatine kinase and lactate dehydrogen-ase activity decreased,and so did blood glucose consumption;The blood sugar level in serum relatively went up.The assimilation of protein decreased,and the oxidative stress of blood became lower.And the increase in albumin may suggest that ovariectomized cows need more lipoprotein fatty acids and other nutrients.

摘要： 【目的】研究去势对西门塔尔牛血清能量、蛋白代谢及抗氧化指标的影响。【方法】选取50头健康的、16月龄的西门塔尔公牛，经药物驱虫后，依据体重进行单因素配对试验设计。【结果】肌酸激酶的活性去势组比未去势组低6.90;，差异显著（P＜0.05）。去势组的尿素氮和白蛋白含量比未去势组分别高5.63;和2.59;，差异极显著（P＜0.01）；白蛋白与球蛋白的比值去势组显著高于未去势组（P＜0.05）。去势组和未去势组的超氧化物歧化酶、谷胱甘肽过氧化物酶和丙二醛含量含量差异均不显著（P＞0.05）。【结论】去势使代谢氧化过程减慢，去势牛变得温顺而活动量相对减少，致使机体对ATP的需求降低了，血清肌酸激酶和乳酸脱氢酶的活性下降了，血糖的消耗降低，血清中血糖水平相对升高；蛋白同化作用减弱，血液的氧化应激变低。而白蛋白增加可能与去势牛需要更多的脂蛋白运势脂肪酸等营养物质有关。