Group housing for pigs is the welfare-preferred approach, but managing social dynamics requires careful attention to group composition, space, and resources to prevent aggression and injury.
Group housing allows pigs to express natural social behaviours including play, mutual investigation, and resting contact, but it also creates risks of aggression and injury that require active management. The welfare quality of group housing depends critically on stability of group membership, adequate space per animal, enrichment provision, and monitoring capacity. Mixing unfamiliar pigs is a welfare risk that should be minimised through stable group management from weaning to slaughter where possible. When mixing is unavoidable, best practice includes providing multiple refuge areas, removing highly aggressive individuals, and increasing enrichment immediately post-mixing.