Carpal, tarsal, and stifle skin lesion prevalence and potential risk factors in Swiss dairy cows kept in tie stalls: A cross-sectional study

The prevalence of skin lesions at the legs of dairy cows often serves as an indicator for animal welfare and is used as a measurement of adequacy of the present housing conditions. The aim of this study was to assess the prevalence of skin lesions at the carpus, tarsus, and stifle in Swiss dairy cows kept in tie stalls and to describe potential risk factors associated with the different types and severities thereof. Skin lesions and potential risk factors were assessed in 627 cows of 27 tie stall farms in a cross-sectional study. The associations of each outcome and the potential risk factors were assessed by means of logistic regression models using farm as the random factor. One odds ratio was obtained for each biologically relevant risk factor category and the final models were compared between the lesion types and locations. Tarsal lesions were recorded most frequently, with a prevalence of 62.2, 34.4, and 24.0% for moderate to severe hair loss, any severity of ulceration, and moderate to severe swelling, respectively. The prevalence of carpal lesions ranged from 54.4% for hair loss, over 7.7% for ulceration, to 6.1% for swelling, while stifle lesions were recorded less frequently with a prevalence of 18.6, 8.9, 3.4% for hair loss, ulceration, and swelling, respectively. The risk for various skin lesion types and locations significantly increased, when the concrete stall base was covered with a rubber mat and the bedding depth was low. Cows were at the lowest risk to develop skin lesions when they had more than 13 days of outdoor exercise per month. The prevalence of skin lesions in tied Swiss dairy cows is remarkably high and could possibly be reduced by providing the herd more frequent outdoor exercise and a well-cushioned, friction-absorbing and non-abrasive lying surface.