Commercial pig systems wean piglets at three to four weeks, far earlier than natural weaning at three to four months. The welfare implications of early weaning are significant and drive multiple subsequent welfare problems.
Early weaning in commercial pig production is a welfare compromise driven by the economic advantage of shorter farrowing intervals. Piglets weaned at 21 days are immunologically and neurologically immature — they have not completed the natural suckling period that supports gut development, immune education, and social learning from the sow. Post-weaning stress syndrome reflects this biological mismatch: the gastrointestinal tract, suddenly deprived of sow's milk, is susceptible to pathogenic bacterial colonisation causing diarrhoea. Belly-nosing of pen-mates — misdirected suckling attempts — demonstrates persistent suckling motivation that is frustrated by premature weaning. Increasing the minimum weaning age to 28 days is a welfare improvement achievable within commercial systems; Scandinavian countries demonstrate that weaning at 28 days is economically viable with appropriate sow management. Transition management — providing familiar bedding material, creep feed containing sow milk components, and stable social groups — reduces stress burden during the unavoidable weaning transition.