1 Laboratory of Animal Husbandry, Faculty of Veterinary Medicine, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
Animal. 2014 Jan;8(1):20-7. doi: 10.1017/S1751731113001717. Epub 2013 Oct 23.
This study investigated the profile of locomotion score and lameness before the first calving and throughout the first (n=237) and second (n=66) lactation of 303 Holstein cows raised on a commercial farm. Weekly heritability estimates of locomotion score and lameness, and their genetic and phenotypic correlations with milk yield, body condition score, BW and reproduction traits were derived. Daughter future locomotion score and lameness predictions from their sires��� breeding values for conformation traits were also calculated. First-lactation cows were monitored weekly from 6 weeks before calving to the end of lactation. Second-lactation cows were monitored weekly throughout lactation. Cows were locomotion scored on a scale from one (sound) to five (severely lame); a score greater than or equal to two defined presence of lameness. Cows��� weekly body condition score and BW was also recorded. These records were matched to corresponding milk yield records, where the latter were 7-day averages on the week of inspection. The total number of repeated records amounted to 12 221. Data were also matched to the farm���s reproduction database, from which five traits were derived. Statistical analyses were based on uni- and bivariate random regression models. The profile analysis showed that locomotion and lameness problems in first lactation were fewer before and immediately after calving, and increased as lactation progressed. The profile of the two traits remained relatively constant across the second lactation. Highest heritability estimates were observed in the weeks before first calving (0.66 for locomotion score and 0.54 for lameness). Statistically significant genetic correlations were found for first lactation weekly locomotion score and lameness with body condition score, ranging from ���0.31 to ���0.65 and from ���0.44 to ���0.76, respectively, suggesting that cows genetically pre-disposed for high body condition score have fewer locomotion and lameness issues. Negative (favourable) phenotypic correlations between first lactation weekly locomotion score/lameness and milk yield averaged ���0.27 and ���0.17, respectively, and were attributed to management factors. Also a phenotypic correlation between lameness and conception rate of ���0.19 indicated that lame cows were associated with lower success at conceiving. First-lactation daughter locomotion score and/or lameness predictions from sires��� estimated breeding values for conformation traits revealed a significant linear effect of rear leg side view, rear leg rear view, overall conformation, body condition score and locomotion, and a quadratic effect of foot angle.
本研究调查了 303 头荷斯坦奶牛在商业农场的首次分娩前和第一次（n=237）和第二次（n=66）泌乳期间的运动评分和跛行情况。得出了运动评分和跛行的每周遗传估计值，以及它们与产奶量、体况评分、BW 和繁殖性状的遗传和表型相关性。还计算了来自其父亲 conformation 性状的育种值的女儿未来的运动评分和跛行预测。第一次泌乳的奶牛从分娩前 6 周开始每周监测，直到泌乳结束。第二次泌乳的奶牛在整个泌乳期间每周监测。奶牛的运动评分范围从 1（正常）到 5（严重跛行）；评分大于或等于 2 定义为跛行。奶牛每周的体况评分和 BW 也有记录。这些记录与相应的产奶量记录相匹配，后者是检查周的 7 天平均值。重复记录的总数达到 12 221 次。数据还与农场的繁殖数据库相匹配，从中得出了五个性状。统计分析基于单变量和双变量随机回归模型。分析表明，第一次泌乳时的运动和跛行问题在分娩前和分娩后立即较少，随着泌乳的进行而增加。这两个特征的特征在第二次泌乳期间相对保持不变。第一次产犊前几周观察到最高的遗传估计值（运动评分 0.66，跛行 0.54）。发现第一次泌乳时每周的运动评分和跛行与体况评分之间存在统计学显著的遗传相关性，范围从 -0.31 到 -0.65 和 -0.44 到 -0.76，这表明在遗传上容易出现高体况评分的奶牛的运动和跛行问题较少。第一次泌乳时每周的运动评分/跛行与产奶量之间的负（有利）表型相关性平均为 -0.27 和 -0.17，这归因于管理因素。跛行与受孕率之间的表型相关性为 -0.19，这表明跛行奶牛的受孕成功率较低。来自父亲 conformation 性状的估计育种值的第一次泌乳的女儿运动评分和/或跛行预测显示后腿侧视图、后腿后视图、整体结构、体况评分和运动的线性效应以及脚角度的二次效应具有显著的线性效应。
