University of Glasgow, School of Veterinary Medicine, Scottish Centre for Production Animal Health and Food Safety, Glasgow G61 1QH, United Kingdom.
The University of Queensland, School of Veterinary Science, Brisbane, Australia 4072.
J Dairy Sci. 2013 Apr;96(4):2283-2292. doi: 10.3168/jds.2012-6173. Epub 2013 Feb 22.
The periparturient period presents major physiological challenges for the dairy cow. It is a period that is affected by metabolic stressors, major changes in endocrine status, and altered immune function, which together result in an increased risk of disease. Immunological, hematological, and metabolic profiles from the periparturient period of heifers (primipara) were compared with those of cows (pluripara) to test the hypothesis that at the time of calving they have qualitatively different peripheral blood profiles. Blood samples were collected from 22 Holstein-Friesian animals on 3 occasions: approximately 2 wk before calving, within 24h after calving, and approximately 2 wk after calving. Quantitative PCR was used to measure the expression of a selected set of cytokines and receptors by peripheral blood leukocytes. Additional analyses included hemoglobin concentration, red cell, platelet and white cell counts (total and differentiated), and clinical diagnostic biochemical profiles. Total leukocyte counts, neutrophils, and lymphocytes were higher in heifers than cows before calving and within 24h after calving. Alkaline phosphatase was consistently higher in heifers than cows and several significant differences were observed between the 2 groups with regards to cytokine and cytokine-receptor mRNA expression. The results warrant further investigation from the perspective of identifying risk factors for metabolic and parturient disease in dairy cattle.
围产期对奶牛来说是一个巨大的生理挑战。这个时期受到代谢应激、内分泌状态的重大变化和免疫功能改变的影响，导致疾病的风险增加。为了验证“在分娩时，它们的外周血液图谱在质量上存在明显不同”这一假说，我们比较了青年牛（初产牛）和奶牛（经产牛）围产期的免疫、血液和代谢特征。从 22 头荷斯坦-弗里森奶牛身上采集了 3 次血液样本：大约在分娩前 2 周、分娩后 24 小时内和分娩后大约 2 周。利用定量 PCR 技术测量外周血白细胞中一组选定的细胞因子和受体的表达。其他分析包括血红蛋白浓度、红细胞、血小板和白细胞计数（总数和分类）以及临床诊断生化特征。在分娩前和分娩后 24 小时内，青年牛的总白细胞计数、中性粒细胞和淋巴细胞计数高于奶牛。碱性磷酸酶在青年牛中的水平始终高于奶牛，而且在两组之间观察到几个细胞因子和细胞因子受体 mRNA 表达方面的显著差异。这些结果值得进一步研究，以确定奶牛代谢和分娩疾病的风险因素。
