Commercial piglet weaning occurs at 3-4 weeks — far earlier than the natural 12-17 weeks. This premature separation causes significant welfare impacts on both sows and piglets.
Weaning stress in commercial pig production represents a cascade of welfare harms compressed into a short period. Sow distress at piglet removal is well-documented — vocalization, restlessness, and attempts to locate piglets last for 24-48 hours. For piglets, simultaneous separation from the mother, mixing with unfamiliar piglets (causing fighting), and dietary transition creates a "triple jeopardy" stress event. Gut immaturity in 3-week-old piglets makes the transition to solid feed challenging, causing widespread post-weaning diarrhea and poor growth. Later weaning — at 5 or more weeks — substantially reduces all these welfare harms but reduces sow reproductive efficiency. In some jurisdictions, minimum weaning ages are legally mandated at 28 days; a higher minimum would protect both piglet and sow welfare.