Increasing dairy cow longevity - the number of lactations before culling - reduces welfare harm, improves sustainability, and increases farm economic efficiency simultaneously.
Dairy cow longevity is a welfare metric that reflects the accumulation of welfare-relevant conditions over a productive life. A cow culled after 2.5 lactations has typically been removed because her welfare has deteriorated to the point that productivity is compromised - lameness, mastitis, and reproductive failure are the proximate causes of culling, and all involve sustained suffering before the culling decision. Farms that achieve 5+ lactation averages have typically done so by preventing the diseases and conditions that cause premature culling. The alignment between longevity, welfare, and sustainability provides a rare case where all three imperatives point in the same direction - making longevity improvement one of the most defensible targets for dairy welfare advocacy.