亚临床酮病奶牛血清中微量元素代谢水平的研究

Study on Metabolism Levels of Serum Trace Elements in Dairy Cows with Subclinical Ketosisin

本试验旨在研究荷斯坦奶牛亚临床酮病对血清中微量元素的影响，选择40头产后1～15d的荷斯坦亚临床酮病奶牛，通过应用原子吸收光谱法测定血清中Cu、Fe、Mn、Zn、Se、Co含量，应用分光光度计和比色法测定血清中GSH—Px、IAOc、T—SOD活力及MDA含量。结果显示，阳性组血清中Cu、Zn、Se、Co的含量在整个检测过程中均极显著低于对照组（P〈0．01）；阳性组血清中Mn的含量在第1、5天的检测中显著低于对照组（P〈0．05），第10、15天极显著低于对照组（P〈0．01）；阳性组血清中Fe的含量与对照组相比差异不显著（P〉0．05）；阳性组血清中GSHPx、T—SOD、T-AOC的活性均极显著低于对照组（P〈0．01）；阳性组血清中MDA的含量极显著高于对照组（P〈0．01）。结果表明，亚临床酮病直接影响奶牛抗氧化系统GSH—Px、T—AOC、T-SOD的活性，间接地影响血清中微量元素Cu、Mn、Se、Zn的含量。Co是维生素B12的重要组成部分，维生素B12在肝脏内的浓度下降，从而导致亚临床酮病血清中Co的含量降低。亚临床酮病奶牛肝脏和氧化酶受损，破坏Fe的结合，机体内贮存的Fe则可以释放出来，维持机体的需要，血清中Fe的含量没有显著的变化。

This study was designed to research the effects on serum trace elements of Holstein cows with subclinical ketosis. 40 Holstein cows with subclinical ketosis in 1 to 15 d postpartum, through the application of atomic absorption spectrometry, we measured Cu, Fe, Mn, Zn, Se, Co contents in serum, determined GSH-Px, T-AOC, T-SOD activities and MDA content in serum by using spectrophotometer and colorimetric. Cu, Zn, Se, Co contents in serum of positive group were extremely significantly lower than that of control group in the whole testing process （P〈0.01） ; Mn concentrations in serum of positive group in the 1st, 5th days detection were significantly lower than the control group （P〈0.05） . 10th, 15th day were extremely significantly lower than the control group （P〈0.01） ; Fe contents in serum of positive group and control group were not signif- icantly different （P〉0. 05）, GSH-Px, T-SOD, T-AOC activities in serum of positive group were extremely significantly lower than the control group （P〈0.01）, MDA content in serum of positive group was extremely significantly higher than the control group （P〈0.01）. Subclinical ketosis had direct impact on GSH Px, T-AOC, T-SOD activities of cows antioxidant system, indirect effect on serum trace elements Cu, Mn, Se, Zn contents; vitamin B12 had the influence on Co content in serum,so Co content in serum significantly decreased in subclinical ketosis cow; the liver and oxidases of subclinical ketosis cow were damaged, resulting in the Fe content in serum had no significant changes.