The post-weaning period is one of the highest-risk periods for pig welfare, with abrupt diet change, social mixing and environmental novelty creating multiple simultaneous welfare challenges.
Weaned piglets simultaneously lose their mother, siblings, familiar pen environment, and milk diet, while being mixed with unfamiliar piglets and moved to a new pen. This multifactorial stressor event causes severe acute stress followed by ongoing disease pressure. The welfare consequences include fighting injuries, diarrhoea, starvation, and mortality. Later weaning, stable social groups, and enriched environments all reduce these welfare impacts.