中文摘要：

根据奶牛血浆钙浓度将奶牛分为试验组和对照组，并设置2个平行试验组。应用iTRAQ／LC-MS／MS技术对2组奶牛样品进行差异表达蛋白的筛选和鉴定，并结合生物信息学软件对试验结果进行分析。试验共得到398个差异表达蛋白，其中2个平行试验组重叠的蛋白为265个，经过筛选共得到14种具有统计学差异的表达蛋白。结合生物信息学分析中的基因功能分析，结果得到74个注释结果，细胞组成、分子功能和生物过程分别为6，12，55个。根据结果分析可知，奶牛亚临床低血钙症生理和病理现象能够从3个方面解释其生理和病理现象，分别是血钙调节、免疫与炎症反应和血液凝固与补体途径。本试验首次应用iTRAQ结合LC-MS／MS技术对亚临床低血钙症奶牛进行蛋白质组学分析，填补该技术对亚临床低血钙症的空白，并提供科学依据。

英文摘要：

The subclinical hypocalcaemia of dairy cows is a metabolic disorder disease. The objective of this study is to find out the novel pathogenesis of the disease by proteomic analysis. In this stud- y, the dairy cows were divided into two groups according to the concentration of blood calcium, and set 2 parallel tests. Then milk samples were analyzed by iTRAQ/LC-MS/MS for detecting and i- dentifying the different proteins. Bioinformatics were carried out for analyzing these different pro- teins. There were 398 proteins were found,and 265 of these were overlap proteins between the two parallel tests. 14 different proteins have a statistical significance. The results of bioinformatics were 74 annotations including 6 cellular component, 55 biological process, and 12 molecular function. With the results of bioinformatics, the calcium regulation, immune and inflammatory response, blood concretion and complement pathway were related with the subclinical hypocalcemia. This study is the first time proteomic analysis for subclinical hypocalcaemia by iTRAQ/LC-MS/MS, and offer the evidence for further research.