Competitiveness and System Evaluation, Agroscope, Tänikon 1, 8356 Ettenhausen, Switzerland.
Competitiveness and System Evaluation, Agroscope, Tänikon 1, 8356 Ettenhausen, Switzerland; Ethology and Animal Welfare Unit, Department of Environmental System Sciences, ETH Zürich, 8092 Zürich, Switzerland; Centre for Proper Housing of Poultry and Rabbits (ZTHZ), Division of Animal Welfare Veterinary Public Health Institute, University of Bern, Burgerweg 22, 3052 Zollikofen, Switzerland.
J Dairy Sci. 2019 May;102(5):4563-4576. doi: 10.3168/jds.2018-15316. Epub 2019 Mar 21.
Increasing societal awareness for animal welfare can promote changes in legislation. Some of these changes may also affect the person that interacts with the animal in a shared workspace, such as in milking stalls. Swiss milking stalls were designed many years ago, when cows were smaller than they are today. A recent animal-based study indicated that welfare decreased in cows exposed to restricted space allowance in milking stalls, which had resulted from increasing body size without adjustment of milking stall dimensions. However, changing the milking stall dimensions without considering the milker may be detrimental. For many years, health issues, particularly of the upper limb and shoulders, have affected milking personnel. The current study investigated the effect of large and standard milking stall dimensions on muscle activity in milkers (as a measure of workload) during milking. This assessment is fundamental to ensure that legislation improving animal welfare does not jeopardize human health. The study took place in an experimental milking parlor that allowed for size adjustment of the individual milking stall. Nine milkers performed 2 shifts of milking in a herringbone and 2 shifts in a side-by-side milking parlor. The milking stall dimensions were large on one side and standard on the other side of the parlor; the 2 sides were switched between milking shifts. We used surface electromyography to monitor bilateral muscle activity of forearm (flexor carpi ulnaris), arm (biceps brachii), and shoulder (deltoideus anterior; upper trapezius) muscles. Statistical analysis was performed separately for the herringbone and the side-by-side parlor for each muscle using mean and maximum muscle activity as the target variables in a linear mixed-effects model. The analysis showed that the different milking stall dimensions did not consistently affect activity of the measured muscles. Our results suggest that milking stall dimensions are not a primary risk factor for poor ergonomics in parlor workers.
提高社会对动物福利的认识可以促进立法的改变。这些变化中的一些也可能影响到在共享工作空间中与动物互动的人，例如在挤奶房中。瑞士的挤奶房是多年前设计的，当时的奶牛比现在小。最近一项基于动物的研究表明，在挤奶房中，由于奶牛体型增大而没有调整挤奶房的尺寸，导致奶牛的活动空间受限，其福利下降。然而，如果不考虑挤奶员而改变挤奶房的尺寸，可能会产生不利影响。多年来，健康问题，特别是上肢和肩部的健康问题，一直困扰着挤奶员。本研究调查了大尺寸和标准尺寸的挤奶房尺寸对挤奶员（作为工作量的衡量标准）在挤奶过程中的肌肉活动的影响。这一评估对于确保改善动物福利的立法不会危及人类健康至关重要。该研究在一个实验挤奶厅进行，该挤奶厅允许调整单个挤奶房的大小。9 名挤奶员在鱼骨式和并列式挤奶厅中各进行了 2 个班次的挤奶。挤奶房的一侧尺寸较大，另一侧尺寸标准，挤奶班次之间切换两侧。我们使用表面肌电图监测前臂（尺侧腕屈肌）、手臂（肱二头肌）和肩部（三角肌前束；斜方肌上部）的双侧肌肉活动。使用线性混合效应模型，分别对鱼骨式和并列式挤奶厅中的每个肌肉，以平均和最大肌肉活动作为目标变量，对统计分析进行了分析。分析结果表明，不同的挤奶房尺寸并不总是影响所测量肌肉的活动。我们的结果表明，挤奶房尺寸不是牛舍工人中不良工效学的主要危险因素。
