Group housing for gestating sows is now required in the EU and supported by welfare science, but implementation challenges affect welfare outcomes.
The transition from individual gestation crates to group housing represents a major welfare advance for sows globally. Individual crates prevent movement, turning and social interaction for months. Group housing restores these capabilities but introduces new challenges: feeding competition causes injuries and stress hierarchies that disadvantage subordinate animals. System design that minimises aggression through individual feeding stations, adequate space and appropriate group stability is critical to realising the welfare benefits of group housing.