New recommendations for self-locking barriers to reduce skin injuries in dairy cows

Cow factors to address when performing avoidance distance tests at the feeding rack

The human-animal relationship is an important component of farm-animal welfare. It is often assessed using 'avoidance distance', i.e. the distance at which animals avoid humans approaching them. However, this avoidance distance may be influenced by factors other than the human-animal relationship such as genetic background or health status. The objective of this cross-sectional epidemiological study was to assess the size of the effect of animal factors and testing conditions on the results of an avoidance test in dairy cows. Five observers applied a standardised test of avoidance distance at the feeding rack on 2 306 lactating cows from 103 dairy farms. We collected data on the independent variables: breed, parity and lameness, and height at withers, and calculated the height difference between the observer standing on the walking alley and each cow restrained at the feeding table. The avoidance distance of the cows, expressed in cm, was modelled using a linear mixed-effect model, with the above-mentioned independent variables as fixed factors, and the farm nested in observer as a random factor. The avoidance distance expressed in four categories as in the Welfare Quality protocol (2009) was modelled using a mixed effects ordinal regression with the same fixed and random factors. For the avoidance distance expressed in cm, we observed that intra-farm variability was twice as large as inter-farm variability (SD: 33.9 cm intra-farm vs 16.7 cm inter-farm). Avoidance distance increased by 7.0 cm (95%CI [3.8-10.2]) when the cow was multiparous and increased by 4 cm (95%CI [0.2-0.6]) when the height difference between observer and cow increased by 10 cm. Avoidance distance decreased by 9.9 cm (95%CI [-19.6 - -0.3]) when the cow was lame and decreased by 6.4 cm (95%CI [-23.4 - -0.4]) when the cow breed was Montbéliarde vs Holstein. For the avoidance distance expressed in categories, there was a significant effect of the height difference and the parity. A greater height difference as well as multiparous cows had a slightly increased likelihood of reaching a higher avoidance distance category. We conclude that avoidance-test results are influenced by cow-related factors (parity, height difference to experimenter, lameness status, and breed). Thus, to reliably use the avoidance distance test to assess the human-animal relationship at farm level, we recommend careful sampling of cows for testing based on these factors. The measured avoidance distance can also be corrected with a coefficient based on animal-specific factors and height difference between observer and cows.

Refinement of international recommendations for cubicles, based on the identification of associations between cubicle characteristics and dairy cow welfare measures

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.