Department of Animal Science, McGill University, Sainte-Anne-de-Bellevue, Quebec, H9X 3V9, Canada.
Dairy Education and Research Centre, University of British Columbia, Agassiz, British Columbia, V0M 1A0, Canada.
J Dairy Sci. 2021 Mar;104(3):3304-3315. doi: 10.3168/jds.2019-17665. Epub 2020 Dec 25.
The overall goal of the study was to develop new recommendations for tie-rail placement combining both vertical and horizontal positions to improve dairy cow welfare. Four treatments were tested: 2 new tie-rail positions that followed the natural neckline of cows when feeding and rising [neckline 1 (NL1), neckline 2 (NL2)], current recommendation (CR), and the average tie-rail position currently found on Quebec farms (current average on farm; CF). All other stall dimensions followed CR based on average cow size. Forty-eight cows blocked by parity and stage of lactation were randomly allocated to a treatment for 10 wk. Live scoring was performed weekly to evaluate injury, cow and stall cleanliness, and bedding quantity. Daily lying time, lying bout frequency, and lying bout duration were continuously recorded using leg-mounted accelerometers. Cows were recorded 1 d/wk by overhead cameras to evaluate lying down and rising events. Tie-rail placement did not affect cow and stall cleanliness, bedding quantity, and lying time. All tie-rail placements tested resulted in neck injuries with the position of neck injuries shifting based on the change in tie-rail placement: CR increased in proximal neck injuries (mean ± standard deviation, difference in injury score from baseline: +0.89 ± 0.153) compared with NL2 (+0.06 ± 0.153), but decreased in medial neck injuries (-0.11 ± 0.166) compared with NL2 (+0.78 ± 0.166) and NL1 (+0.53 ± 0.166). All treatments showed a decrease over time in average lying intention time (mean, difference between overall short- and long-term: -5.8 s/event), lying-down time (-1.1 s/event), contact with stall during lying (-32.5%), slipping during lying (-9.1%), backward movement on knees during rising (-10.9%), contact with tie-rail during rising (-14.3%), and overall abnormal rising (-15.6%) over time. Although lying and rising ability improved over time, abnormal lying and rising behaviors were still highly prevalent in the long term. Overall, our results show that dairy cows are limited in their ability to move within their environment without coming in contact with the stall confines (tie-rail and divider bars), warranting further research to determine alternatives to metal tie-rail bars, such as a flexible bar or chain, or provide fewer obstacles through the elimination of some stall hardware.
本研究的总体目标是制定新的牛颈枷位置建议，综合考虑垂直和水平位置，以提高奶牛福利。本研究共测试了 4 种处理方法：2 种新的牛颈枷位置（NL1 和 NL2）遵循奶牛采食和起身时的自然颈线，当前推荐位置（CR）和魁北克农场目前平均牛颈枷位置（农场平均位置；CF）。所有其他牛卧床尺寸均基于平均奶牛大小遵循 CR。48 头奶牛按胎次和泌乳阶段分组，随机分配到一种处理方法中，持续 10 周。每周进行活体评分，以评估损伤、奶牛和牛卧床清洁度以及卧床垫料量。使用腿部安装的加速度计连续记录每日卧息时间、卧息时长和卧息次数。每周 1 次使用头顶摄像机记录奶牛卧息和起身事件。牛颈枷位置不影响奶牛和牛卧床清洁度、卧床垫料量和卧息时间。所有测试的牛颈枷位置均导致了颈部损伤，颈部损伤的位置随着牛颈枷位置的变化而变化：与 NL2 相比，CR 增加了颈部近端损伤（损伤评分差值：+0.89 ± 0.153），但减少了颈部中间损伤（-0.11 ± 0.166），与 NL2（+0.78 ± 0.166）和 NL1（+0.53 ± 0.166）相比。所有处理方法的平均卧息意愿时间（总体短期和长期差值：-5.8 s/事件）、卧息时间（-1.1 s/事件）、卧息时与牛卧床的接触时间（-32.5%）、卧息时滑倒（-9.1%）、起身时膝关节向后移动（-10.9%）、起身时与牛颈枷接触（-14.3%）和总体异常起身（-15.6%）均随时间逐渐减少。尽管奶牛的卧息和起身能力随时间逐渐提高，但长期来看，异常卧息和起身行为仍普遍存在。总的来说，我们的研究结果表明，奶牛在不接触牛卧床围栏（牛颈枷和隔栏）的情况下，其在环境中的活动能力有限，因此需要进一步研究，以确定金属牛颈枷的替代物，如柔性牛颈枷或链条，或通过消除一些牛卧床硬件来减少障碍物。
