Environmental enrichment is now legally required for pigs in the UK and EU, and the type and quality of enrichment significantly affects welfare outcomes.
Pig enrichment welfare is not binary - the presence or absence of enrichment material - but a continuum determined by material type, quantity, accessibility, and novelty. Legislation requiring enrichment has improved baseline standards but compliance that provides minimal, ineffective enrichment may not substantially improve welfare. Rooting is one of the strongest behavioural motivations in pigs, and enrichment that allows this behaviour - straw, wood shavings, earth - substantially reduces the frustration that drives tail biting and other harmful behaviours. Research on optimal enrichment demonstrates that quantity matters alongside quality: insufficient straw causes competition that defeats its purpose, while abundant, frequently replenished straw provides sustained welfare benefits.