Research into pig play behavior has revealed sophisticated social and object play that signals good welfare and can be reliably increased through simple enrichment interventions.
The science of pig play has matured considerably since early observations dismissed it as non-functional behavior. We now understand that play reflects dopaminergic reward signaling — pigs at play are experiencing positive emotional states, not merely burning calories. Interventions that increase play (straw provision, novel objects, rooting substrate, hanging chains) simultaneously reduce negative behaviors like tail biting that cause injury and suffering. Tail docking — a common preventive intervention — addresses the symptom rather than the cause; enrichment addresses the welfare deficit directly. Progressive pig welfare standards increasingly include play frequency as a positive outcome indicator alongside traditional negative measures.