[Prevalence of claw disorders in swiss cattle farms]

The project «Healthy claws - the foundation for the future» aims to establish a Swiss national claw health monitoring based on digital recordings by claw trimmers during claw trimming. To assess claw health on the participating farms, between-herd prevalence, within-herd prevalence and cow prevalence of all claw disorders based on the «ICAR Claw Health Atlas» were calculated during this study. Claw trimmers underwent an intensive training and examination in order to ensure data quality. To guarantee the representativity of the prevalences, only farm claw trimmings were considered, where ≥ 80 % of the cows in a herd were trimmed. The calculations were based on 7108 cows and 403 heifers from 238 farms, during the period from February 2020 to February 2021. At least one claw disorder was present in 99,2 % of the farms, with 49,6 % of the heifers and 77,7 % of the cows having at least one claw disorder. The high prevalence is seen as a result of all ICAR claw disorders being considered, whereas not all of them are painful and consequently not all of them cause lameness. The absence of lameness assessment limits the evaluation of existing herd problems. High between-herd and cow prevalences were observed for the following claw disorders: heel horn erosion (92,9 %/64,7 %), digital dermatitis (55,9 %/20,7 %), white line disease (81,5 %/17,7 %) and sole hemorrhage (66,4 %/11,6 %). Asymmetric claws, corkscrew claws, scissor claws, horn fissure, interdigital phlegmon, swelling of the coronet and/or bulb and toe necrosis had low prevalences. The proportion of cows treated with a hoof block (0,5 %) was comparatively small in regard of the cows suffering from ulcers (5,6 %) and white line abscesses (2,5 %). The median within-herd prevalence of digital dermatitis was 5,6 %, with a maximal within-herd prevalence of 87,5 %. Despite the contagious nature of digital dermatitis, no increase of between-herd and cow prevalence has been observed in the past ten years throughout Switzerland. Based on this data, the Swiss claw health situation can be monitored, compared over time and improved in the future.