中文摘要：

为研究亚临床酮病奶牛的氧化应激状态及其对奶牛乳品质的影响,分别选取21头亚临床酮病奶牛和21头健康奶牛,通过尾静脉采集非抗凝血,用于氧化抗氧化指标的检测;同时收集新鲜乳样,用于乳成分的检测。结果表明,与健康奶牛相比,亚临床酮病奶牛的总抗氧化能力、谷胱甘肽过氧化物酶、乳蛋白和总固形物活性、血清葡萄糖显著或极显著降低（P〈0.05;P〈0.01）,乳脂肪比、非酯化脂肪酸、β-羟基丁酸、丙二醛含量显著或极显著升高（P〈0.05;P〈0.01）。由此可见,亚临床酮病奶牛体内存在氧化应激,主要抗氧化酶活性降低,并且氧化应激状态显著高于健康奶牛,乳品质低于健康奶牛。

英文摘要：

This study was conducted to investigate the oxidative and antioxidative status and the milk quality of subclinical ketosis on. 21 subclinical ketotic dairy cows and 21 normal dairy cows were chosen, respectively. Blood samples were collected from caudal vein to obtain serum for detec- ting oxidative and antioxidant status. Fresh milk samples were collected for milk composition anal- ysis. The results showed as follows：compared with normal cows, total antioxidant capacity, gluta thione peroxidase, milk protein, total solids and glucose were significant or extremely significantly reduced （P〈0.05 ; P〈0.01） ; milk fat ratio, nonesterifed fatty acid, beta-hydroxybutyrate and ma londialdehyde were significantly or extremely significanty increased （（P〈0.05;P〈0.01）. In sum- mary,oxidative stress existed in subclinical ketosis, the activity of the main antioxidant enzyme was depressed, being in the oxidative stress and the milk quality dropping.