Animal welfare science is increasingly moving beyond the prevention of suffering to the active promotion of positive emotional states. Research on pig positive affect — including play, curiosity, and social bonding — is transforming how welfare is assessed and improved in commercial production systems.
Positive affect in pigs is not merely the absence of negative states — it is an active wellbeing dimension requiring environmental and management conditions to express. Pigs in enriched environments with rooting substrate, space for running, and stable social groups show optimistic cognitive bias consistent with positive emotional states. Pigs that play frequently show lower cortisol, better immune function, and lower aggression. Positive stockmanship creates trust: pigs that associate humans with positive interactions show lower fear responses during routine handling, reducing stress for both pigs and handlers. The challenge for commercial production is creating economically viable systems that actively promote positive pig welfare rather than merely reducing suffering.