Early weaning of piglets in commercial systems causes significant welfare harm to both sow and piglets, with the timing and management of weaning being critical welfare factors.
Pig weaning welfare reveals a fundamental conflict between commercial productivity and natural behavioral needs. Piglets weaned at 3-4 weeks in commercial systems have immature digestive, immune, and behavioral development compared to naturally weaned piglets. Post-weaning belly nosing - redirected suckling behavior on penmates' abdomens - is a welfare indicator of early weaning stress that can cause significant injury. Sows subjected to repeated early separation cycles experience repeated acute distress. Extended weaning ages closer to natural timing improve welfare but require accepting lower annual reproduction rates - a genuine welfare-productivity trade-off that commercial systems have historically resolved in favor of productivity.