The average dairy cow in intensive systems is culled at 3-4 years — a fraction of her natural lifespan — and this premature death reflects the welfare burdens imposed by high-production dairy systems.
Dairy cow longevity is simultaneously a welfare indicator, a sustainability metric, and an economic signal. Short productive lives reflect cumulative welfare burdens — the metabolic stress of high milk production, the pain of lameness and mastitis, and the reproductive failures that follow from physiological depletion. A system in which the average dairy cow lives less than a quarter of her natural lifespan is a system in which the animals are being worked beyond their physiological capacity to sustain. The welfare reform agenda for dairy is therefore partly about longevity: selecting for functional traits alongside milk yield, managing metabolic stress through transition cow nutrition, addressing lameness proactively rather than reactively, and measuring productive lifespan as a welfare outcome indicator.