Lameness in dairy heifers; impacts of hoof lesions present around first calving on future lameness, milk yield and culling risk.

•More severe claw horn lesions were associated with increased risk of future lameness.•More severe sole lesions were associated with reduction in daily yield of 2.68kg.•Managing heifers to reduce severe lesions is likely to have positive herd impacts.•Mild claw horn lesions associated with reduced risk of future lameness and culling.•Mild insult may lead to adaptive changes in the hoof which are beneficial.