Westin R, Vaughan A, de Passillé A M, DeVries T J, Pajor E A, Pellerin D, Siegford J M, Vasseur E, Rushen J
UBC Dairy Education and Research Centre, University of British Columbia, Agassiz, British Columbia, Canada, V0M 1A0.
UBC Dairy Education and Research Centre, University of British Columbia, Agassiz, British Columbia, Canada, V0M 1A0.
J Dairy Sci. 2016 Jan;99(1):551-61. doi: 10.3168/jds.2015-9737. Epub 2015 Nov 5.
Lying down and resting are important for optimal cow health, welfare, and production. In comparison with free stall farms with a milking parlor, farms with automated milking systems (AMS) may place less constraint on how long cows can lie down. However, few studies report lying times on AMS farms. The aims of this study were to describe the variation in lying times of dairy cows in AMS farms and to understand how much of the variation in individual lying times is related to cow-level factors, including lameness, the presence of hock and knee lesions, and body condition score (BCS). We visited 36 farms in Canada (Quebec: n = 10; Ontario: n = 10; British Columbia: n = 4; and Alberta: n = 5), and the United States (Michigan: n = 7). Gait scores, presence of hock and knee lesions, and BCS were recorded for 40 Holstein cows from each herd. Parity and days in milk were retrieved from farm records. Lying time was recorded across 4d using accelerometers (n = 1,377). Multivariable analysis was performed. Of scored cows, 15.1% were lame (i.e., obviously limping; 203 of 1,348 cows). Knee lesions were found in 27.1% (340 of 1,256 cows) and hock lesions were found in 30.8% (421 of 1,366 cows) of the animals. Daily lying time varied among cows. Cows spent a median duration of 11.4 h/d lying down (25th-75th percentile = 9.7-12.9 h), with a lying bout frequency of 9.5 bouts/d (25th-75th percentile = 7.5-12 bouts/d) and a median bout duration of 71 min (25th-75th percentile = 58-87 min/bout). Lameness was associated with cows lying down for 0.6 h/d longer in fewer, longer bouts. Increased lying time was also associated with increased parity, later stage of lactation and higher BCS. Older cows (parity ≥ 3) spent about 0.5 h/d more lying down compared with parity 1 cows, and cows with BCS ≥ 3.5 lay down on average 1 h/d longer than cows with BCS ≤ 2.25. Hock lesions were associated with shorter lying times in univariable models, but no associations were found in the multivariable models. We concluded that only a small proportion of the variation between cows in lying time is explained by lameness, leg lesions, and BCS.
躺卧和休息对于奶牛的最佳健康、福利和生产至关重要。与设有挤奶厅的散栏式牛场相比，采用自动挤奶系统（AMS）的牛场对奶牛躺卧时间的限制可能更少。然而，很少有研究报告AMS牛场的躺卧时间。本研究的目的是描述AMS牛场中奶牛躺卧时间的变化情况，并了解个体躺卧时间的变化中有多少与奶牛个体因素有关，包括跛足、跗关节和膝关节损伤以及体况评分（BCS）。我们走访了加拿大的36个牛场（魁北克：n = 10；安大略：n = 10；不列颠哥伦比亚：n = 4；艾伯塔：n = 5）以及美国的7个牛场（密歇根：n = 7）。记录了每个牛群中40头荷斯坦奶牛的步态评分、跗关节和膝关节损伤情况以及BCS。胎次和泌乳天数从农场记录中获取。使用加速度计在4天内记录躺卧时间（n = 1377）。进行了多变量分析。在有评分的奶牛中，15.1%跛足（即明显跛行；1348头奶牛中有203头）。在1256头奶牛中，27.1%（340头）发现有膝关节损伤，在1366头奶牛中，30.8%（421头）发现有跗关节损伤。奶牛的每日躺卧时间各不相同。奶牛每天躺卧的中位时长为11.4小时（第25 - 75百分位数 = 9.7 - 12.9小时），躺卧回合频率为每天9.5次（第25 - 75百分位数 = 7.5 - 12次），中位回合时长为71分钟（第25 - 75百分位数 = 58 - 87分钟/回合）。跛足与奶牛每天多躺卧0.6小时相关，躺卧回合次数更少但更长。躺卧时间增加还与胎次增加、泌乳后期以及更高的BCS相关。与一胎奶牛相比，年龄较大的奶牛（胎次≥3）每天多躺卧约0.5小时，BCS≥3.5的奶牛平均比BCS≤2.25的奶牛每天多躺卧1小时。在单变量模型中，跗关节损伤与躺卧时间较短相关，但在多变量模型中未发现相关性。我们得出结论，跛足、腿部损伤和BCS只能解释奶牛躺卧时间差异的一小部分。
