Pigs are highly intelligent, social animals whose behavioural needs in farm settings require environmental enrichment that allows exploration, rooting, and play behaviours.
The cognitive complexity of pigs means that barren housing causes significant psychological welfare harm beyond simple physical deprivation. Pigs in bare, unstimulating environments redirect natural rooting and exploration motivation toward pen-mates, causing the tail biting and ear biting that are major welfare and production problems in intensive systems. Straw and other fibrous manipulable materials satisfy rooting motivation and reduce these problems dramatically. The welfare case for enrichment in pig housing is among the best-evidenced in farm animal science — enriched pigs show lower stress indicators, fewer injuries, and better growth than barren-housed pigs. EU minimum requirements represent a floor, not an adequate standard.