The housing system for pregnant sows during gestation has profound effects on their welfare, with significant variation in outcomes between conventional and enriched systems.
Gestation stall confinement prevents sows from turning around, social interaction, and all natural behaviors for the majority of their 16-week pregnancy. Research consistently demonstrates higher welfare harm in sow stalls compared to appropriately managed group housing: higher cortisol, more stereotypic behaviors, worse cardiovascular fitness from immobility, and greater vulnerability to injury from muscle wastage. Group housing is not without welfare challenges - aggression at mixing causes injuries - but well-managed static group systems with space allowances above minimum requirements achieve substantially better welfare outcomes. The slow pace of global sow stall reform means millions of sows worldwide continue to experience this avoidable welfare harm.