Early weaning is standard in intensive pig production but causes significant welfare harm to both piglets and sows, with later weaning systems offering welfare improvements.
Weaning age is a critical welfare decision in pig production that affects millions of sows and hundreds of millions of piglets annually. Early weaning at 21-28 days removes piglets before their immune systems are mature and before the natural development of behavioral independence. The resulting welfare harms are acute and well-documented: distressed piglets vocalize for hours, engage in redirected suckling on pen-mates, and show elevated cortisol. Sows also experience abrupt separation from offspring to which they have formed maternal bonds. Later weaning at the legal minimum or beyond, extended suckling systems, and nurse sow programs that provide continued lactation for piglets represent welfare improvements within commercial constraints.