2021-02, Lardy, Romain, des Roches, Alice de Boyer, Capdeville, Jacques, Bastien, Renaud, Mounier, Luc, Veissier, Isabelle

Maladjusted cubicles for dairy cattle may cause increased skin alterations, lameness, and dirtiness. The International Commission of Agricultural and Biosystems Engineering has produced several recommendations for cubicle design, but a previous study showed that not all of them seem efficient. Here, we aim to refine and complete these recommendations. We collected data on 76 dairy farms (2,404 cows). We modeled the association between combinations of cubicle properties (e.g., type of bedding litter) and dimensions (e.g., cubicle width) relative to cow size, and prevalence of cow skin alterations, lameness, and dirtiness. We used weighted multivariable logistic regression models to predict the presence of skin alteration on the carpus; the neck, shoulder, and back; the flank, side, and udder; and the tarsus or hindquarters. We also evaluated the presence of lameness as well as the dirtiness of the lower hind legs including hocks; the hindquarters, upper hind legs, and flank; the cow rear including tail; and the udder. The risk factors highlighted led us to recommend (1) position cubicles in a way that leaves more than 1 m of clearance from any obstacle in front of the cubicle; (2) if there is an obstacle on the lateral plane (i.e., where the cubicle partition is) in front ahead of the cow, put the obstacle in front of the fore knees; (3) if there is an obstacle in front of the cow on the median plane (e.g., neck or front rail), the position the obstacle between 1.25 and 1.5 of the cow length from the curb and between 1.0 and 1.25 of its height; (4) use curb height between 0.11 and 0.15 of cow height with no sharp edges on the curb; (5) use round or at least has no sharp edges brisket board; (6) use a stone-free soil instead of concrete or use a mattress thicker than 1 cm, with microrelief, and a soft fixing area at the curb, (7) litter with straw (rather than nothing or sawdust) and keep it dry. This risk factor analysis should be followed by experiments in controlled environments to further validate these conclusions and used to update the International Commission of Agricultural and Biosystems Engineering recommendations.

2020-03-30, Lardy, Romain, de Boyer des Roches, Alice, Capdeville, Jacques, Bastien, Renaud, Mounier, Luc, Veissier, Isabelle

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.