Transitioning from individual to group housing for gestating sows represents a major welfare improvement. Understanding how to manage this transition effectively is critical for farmer and pig welfare.
Group housing transition welfare involves both the clear welfare improvements over gestation crates and the management challenges that determine whether those improvements are fully realized. At mixing events — when new sows enter established groups — aggression can cause injuries, including vulva biting and lameness, that represent welfare harms. Management protocols including stable group formation with delayed mixing after insemination, providing sufficient space to minimize competition, and using ESF to prevent food aggression are all evidence-based strategies. Well-managed group housing produces sows with better muscle condition, fewer lameness problems, and more natural social behavior. Poorly managed group housing can produce worse welfare than individual housing. The key variable is management quality, making farmer training essential.