Play behaviour in pigs is a validated indicator of positive welfare states, and systems that elicit play provide evidence of good welfare beyond the absence of suffering.
The presence of play in pigs is a reliable signal of positive emotional states. Environments that support play provide evidence that pigs are not merely surviving but experiencing states that constitute good welfare. Incorporating play observation into farm welfare assessment moves beyond minimum standards to evaluate whether pigs are thriving. This positive welfare approach represents the frontier of farm animal welfare science.