Researchers at the University of Wisconsin have demonstrated that acute (M2*) digital dermatitis (DD) in 16 – 25 month old heifers can increase heel height, claw angle and depth of the interdigital cleft. They speculate that, to reduce the discomfort caused by DD, cattle tend to stand on their toes, taking weight off their heels. This change in stance results in increased claw heel height. Since dorsal wall length remained unchanged, a significant increase in claw angle was observed in feet affected by acute (M2) DD. The increased depth of the interdigital cleft was probably due to inflammation of skin tissue and the prominence of the DD lesion in relation to the surrounding healthy skin.
Another interesting finding from this study was the very large increase in severe heel horn erosion in heifers that had M2 lesions (shown in the graph below).
Given that changes in hoof conformation usually occur before lameness is detected and that effects detected early can be reversible, active surveillance and prompt treatment of M2 lesions are recommended to improve digital dermatitis control programs and claw health.
* a description of digital dermatitis M-stages is here
source: Arturo Gomez et al., Journal of Dairy Science 98:927 (Feb 2015)