Transitioning pregnant sows from individual stalls to group housing systems improves welfare outcomes but requires careful management of aggression and resource access to ensure all animals benefit from the change.
The transition from individual sow stalls to group housing represents genuine welfare progress for pregnant pigs, but the welfare benefits only materialize when the transition is managed well. Poorly managed group housing can produce worse welfare outcomes than stalls through chronic aggression, resource competition and the stress of repeated social group disruption. Key management factors include forming stable groups early and maintaining them across reproductive cycles, using physical barriers at feeding stations to prevent competition, providing adequate floor space per animal, and ensuring sufficient resting area for all sows simultaneously. When these conditions are met, group-housed sows show behaviorally rich, low-stress social lives that represent a genuinely improved welfare outcome compared to the barren isolation of individual confinement.