Review of White Line Disorders in Zone 3 and Toe Tip Necrosis in Dairy Cows and Recent Insights into Aetiopathogenesis and Treatments.

Abstract

White line disorders represent the most prevalent claw horn disruption lesion in dairy cattle. Recent studies have yielded new insights into the appropriate treatment modalities for these lesions. The aims of this study are to elucidate the pathogenesis of white line disorders and its associated claw lesions, such as toe tip necrosis, and to discuss practical treatment applications. In Western Europe, many herds are endemically infected with digital dermatitis. White line disorders in zone 3 and toe tip necrosis starting in zone 1-often beginning as axial white line lesions-frequently exhibit a suboptimal response to standard treatments, including corrective trimming, the application of a hoof block on the healthy claw and the administration of NSAIDs, due to secondary infections with Treponema spp. This study addresses the current perspectives on the aetiopathogenesis of white line disorders and the therapeutic challenges in promoting complete recovery and the correct use of antibiotics, along with preventive measures, such as good flooring. An important factor of its pathogenesis is a decrease in body condition around parturition, Correct diagnosis can be made via the use of regular locomotion scoring and good diagnostic tools, and thin soles by among others overtrimming should be prevented. Current therapeutic methods consist of the prompt application of a block and an NSAID and, in some circumstances, a parenteral injection with antibiotics when there is no good response to the applied therapies.