Gestation crates confine pregnant sows in stalls too small to turn around for most of their productive lives, causing severe welfare harms that have led to bans across the EU, UK, and many US states.
Gestation crate confinement causes severe, well-documented welfare harm to sows across multiple dimensions. Physical welfare is compromised by muscle atrophy, bone mineral loss, and cardiovascular deconditioning from near-complete movement restriction throughout pregnancy. Psychological welfare is profoundly affected: pigs are intelligent, motivated animals with strong drives to root, explore, and interact socially; denial of all of these for months on end causes frustration and psychological distress evidenced by the high prevalence of stereotypic bar-biting and sham-chewing in confined sows. The welfare harms extend to the health of subsequent litters, as sows in poor physical condition produce piglets with lower birth weights and viability. Group housing systems, which have been successfully implemented at large commercial scale, allow sows to move, engage in limited social behaviour, and express a broader range of natural behaviours. While group housing introduces new management challenges around aggression, these are manageable and do not approach the severity of the welfare harms caused by gestation crates.