Perspectives from Canada on Dairy Cows’ Longevity
Authors: Elsa Vasseur and Gabiel M. Dallago and Abdoulaye Baniré Diallo
Date: 2025-08-01
Status: Published
Our focus is ensuring the sustainable life of dairy cattle, or, how to keep healthy, comfortable animals longer in the herd, encompassing research on animal welfare for better management and facilities, together with our understanding of cow longevity. Our approach is to develop methods to remotely assess changes in cow welfare, and to evaluate how health issues and other risk factors are linked to cow longevity. We aimed to exploit the potential of the considerable dataset regularly collected on Canadian dairies via the Canadian Dairy Network (Lactanet). We have assessed the impact of health events such as lameness and mastitis, finding that primiparous cows afflicted with these diseases have reduced milk yields and gross profit, and higher risk of culling than healthy cows. We also unveiled valuable insights on early-life variables that are linked with future productivity and longevity, such as weight at birth and at weaning, weaning age, and serum IgG levels; these represent early indicators that can be used to select replacement animals based on their potential, and reduce economic and environmental losses incurred by keeping animals that will likely never be profitable. Our work has also led to innovations in the remote detection of welfare. On a herd basis, the analysis of DHI indicators routinely collected on dairies was used to develop a composite herd welfare index. On an individual cow basis, we have tested the use of spectral data from milk samples as a source of information on cow-specific changes in welfare status; this approach was successful in linking milk components with improvements in specific outcomes of cow welfare. Overall, these innovations show that the potential to conduct remote assessments is present and could thus be extended to more specific topics (e.g., lameness in individual cows) and other aspects (e.g., economic and environmental performance of cows and farms).