Department of Dairy and Animal Science, The Pennsylvania State University, University Park 16802, USA.
J Dairy Sci. 2012 Nov;95(11):6384-7. doi: 10.3168/jds.2012-5593. Epub 2012 Sep 12.
Telomere length variation may provide a quantitative measure of the effects of dairy management and selection practices on animal stress and welfare. The objective of this study was to evaluate the association between telomere length in Holstein cattle with age, herd, and survival. A multiplex quantitative PCR (qPCR) procedure was utilized to estimate telomere length for 201 Holstein cows from 10 herds following DNA extraction from blood. Primers were designed to amplify a 79-bp telomere product and a 144-bp product of a standard reference gene (β-globin). Both primer sets were included in the same reaction well to enable the analysis of relative quantity (qT) of telomere product compared with β-globin product. Triplicate samples were run for each cow, and mixed models were used to analyze the qPCR results. Younger cows were significantly associated with higher qT, and significant variation was observed among herds for qT. Cows with short telomeres were more likely to be culled in the subsequent year than cows with above-average telomere lengths. Multiplex qPCR provides a cost-effective method of assessing telomere length. Variation in telomere length might provide insights into how management practices and genetic selection influence cow stress and physiological responses to stress.
端粒长度的变化可以为评估奶牛管理和选育实践对动物应激和福利的影响提供定量指标。本研究旨在评估荷斯坦奶牛的端粒长度与年龄、牛群和存活率之间的关系。从 10 个牛群的血液中提取 DNA 后，采用多重实时定量 PCR（qPCR）程序来估计 201 头荷斯坦奶牛的端粒长度。设计了一对引物来扩增 79bp 的端粒产物和 144bp 的标准参照基因（β-珠蛋白）产物。这两个引物组都包含在同一个反应管中，以便能够分析与β-珠蛋白产物相比的端粒产物的相对数量（qT）。每头牛重复进行 3 次样本分析，并采用混合模型来分析 qPCR 结果。年轻的奶牛与更高的 qT 显著相关，并且 qT 在牛群之间存在显著差异。端粒较短的奶牛在下一年被淘汰的可能性高于端粒长度高于平均水平的奶牛。多重 qPCR 为评估端粒长度提供了一种经济有效的方法。端粒长度的变化可能为了解管理实践和遗传选择如何影响奶牛的应激和对应激的生理反应提供了线索。
