Lameness in Pasture-Based Dairy Farms in NSW, Australia

Abstract

Lameness is one of the most important welfare issues in the dairy industry with all cows being at risk during their productive life. It decreases milk production, compromises fertility and increases the chance of being culled. To reduce the likelihood of lameness in cows, a thorough knowledge of the risk factors is essential. Risk factors have been found to differ between farming systems which highlighted the need for a project to identify risk factors of lameness in NSW pasture-based dairies. The thesis reviews the literature on risk factors pertaining to lameness in dairy cattle worldwide with focus on the main aspects of lameness regarding pasture-based dairy farming. First study investigates the prevalence and the potential risk factors for lameness in 62 pasture-based dairies in NSW with the aim to identify risk factors for lameness and to provide the industry with an indication as to the relative contribution of these risks so that dairy producers could allocate their resources to areas most likely to have the greatest impact when planning a prevention strategy. The data gathered through the interviews with farmers focuses on their perception of lameness in their herds. International experience suggests farmers’ perception of lameness are less than the true prevalence, which was proved to be the case in NSW, Australia. The reduced perception of lameness appears to be associated with delayed treatment and poor treatment outcome. Treatment outcomes may be further compromised by almost 30% of farmers or farm staff not having undergone training as to how to effectively trim and treat lame cows. The final study gathers data on wooden hoof blocks commonly used in treatment of lame cows. This study assesses the association between wood density, longevity, and wear characteristics of wooden hoof blocks. It was found that the hardness of the commercial blocks is insufficient to provide an appropriate duration of protection for healing claw lesions.