Lardy R, de Boyer des Roches A, Capdeville J, Bastien R, Mounier L, Veissier I
Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, Saint-Genès-Champanelle63122, France.
Institut de l'Elevage, Antenne de Toulouse-Castanet-Tolosan, Castanet-Tolosan Cedex31321, France.
Animal. 2020;14(8):1745-1756. doi: 10.1017/S175173112000052X. Epub 2020 Mar 30.
The design of self-locking barriers can affect cows' skin injuries and impair welfare. This study aimed to propose and refine recommendations, expressed relatively to the cows' dimensions, for self-locking barrier design to reduce risks for skin injuries on the neck/shoulder/back and on carpus of dairy cows. We recorded individual body dimensions and the dimensions of self-locking barriers (e.g. top rail height) and assessed skin injuries on 3801 cows from 131 loose-housing dairy farms. We explored the significant associations between presence/absence of skin injuries and self-locking barrier dimensions using weighted multivariable logistic regression, taking into account the diversity of feeding barriers within each farm. The robustness of the models was assessed by cross-validation. Cows had skin injuries mainly on the neck/shoulder/back (29.0%) and, to a lesser extent, on the carpus (14.0%). The final multivariable logistic regression models comprised 13 factors for skin injuries on the neck/shoulder/back, and 11 factors for skin injuries on the carpus. Skin injuries were significantly reduced when the self-locking barriers were inclined (neck/shoulder/back) and when the cows used a feeding table (i.e. flat) instead of a feeding manger or cribs (i.e. hollow) (carpus). A top rail height >1.05 × cow height (measured at withers) was significantly associated with fewer skin injuries on the neck/shoulder/back and on carpus. Skin injuries on the neck/shoulder/back and carpus were significantly reduced when the bottom rail was on the food side relative to the wall, and at a height <0.39 of cow height. Skin injuries were significantly less frequent when the separation wall had no sharp edges on the food side (neck/shoulder/back), was >0.4 of cow height (carpus), was thinner than 15 cm (neck/shoulder/back and carpus) and when the height of the feeding step was 0.04 to 0.1 of cow height (neck/shoulder/back) and the length of the feeding step was <0.2 of cow length (carpus). A headlock articulation nut positioned between 0.62 and 0.78 of cow height significantly reduced skin injuries on the neck/shoulder/back. Here, by combining the diversity of on-farm self-locking barriers and their respective dimensions, we were able to refine the International Commission of Agricultural and Biosystems Engineering recommendations for self-locking barrier design and to propose new ones. This information now needs to be confirmed on other datasets, but can already help farmers and dairy industry stakeholders improve the design of self-locking barriers to improve dairy cow welfare.
自锁式围栏的设计会影响奶牛的皮肤损伤并损害其福利。本研究旨在针对自锁式围栏设计提出并完善基于奶牛体型尺寸的建议，以降低奶牛颈部/肩部/背部以及腕关节处皮肤受伤的风险。我们记录了个体奶牛的身体尺寸以及自锁式围栏的尺寸（如顶栏高度），并对来自131个散栏式奶牛场的3801头奶牛的皮肤损伤情况进行了评估。我们使用加权多变量逻辑回归探索了皮肤损伤的有无与自锁式围栏尺寸之间的显著关联，同时考虑了每个农场内饲喂围栏的多样性。通过交叉验证评估模型的稳健性。奶牛的皮肤损伤主要发生在颈部/肩部/背部（29.0%），腕关节处的损伤程度相对较轻（14.0%）。最终的多变量逻辑回归模型包含了13个与颈部/肩部/背部皮肤损伤相关的因素，以及11个与腕关节处皮肤损伤相关的因素。当自锁式围栏倾斜时（颈部/肩部/背部），以及当奶牛使用饲喂台（即平面）而非饲喂槽或饲 crib（即中空）时（腕关节处），皮肤损伤显著减少。顶栏高度大于奶牛肩高的1.05倍与颈部/肩部/背部以及腕关节处较少的皮肤损伤显著相关。当底栏位于靠近墙壁的食物一侧且高度小于奶牛身高的0.39时，颈部/肩部/背部以及腕关节处的皮肤损伤显著减少。当分隔墙在食物一侧没有尖锐边缘时（颈部/肩部/背部）、高度大于奶牛身高的0.4时（腕关节处）、厚度小于15厘米时（颈部/肩部/背部和腕关节处），以及当饲喂台阶的高度为奶牛身高的0.04至0. I时（颈部/肩部/背部）且饲喂台阶的长度小于奶牛体长的0.2时（腕关节处），皮肤损伤的发生频率显著降低。位于奶牛身高的0.62至0.78之间的头锁关节螺母显著减少了颈部/肩部/背部的皮肤损伤。在此，通过结合农场自锁式围栏的多样性及其各自的尺寸，我们能够完善国际农业和生物系统工程委员会关于自锁式围栏设计的建议并提出新的建议。这些信息目前需要在其他数据集上得到证实，但已能帮助农民和奶牛行业利益相关者改进自锁式围栏的设计，以提高奶牛福利。
