The transition from individual stall housing to group housing for gestating sows is mandated in the EU and adopted voluntarily by leading producers worldwide. Successful group housing implementation protects sow welfare through space allowance, feeding system design, and careful mixing management.
Mixing aggression is the primary welfare risk in group housing systems. Careful design of mixing protocols — same-weight groups, introduction of multiple unfamiliar sows simultaneously rather than individually, provision of escape routes and visual barriers — reduces injury severity. Ad libitum straw or rooting substrate reduces redirected aggression by satisfying exploration motivation. Electronic sow feeders virtually eliminate competition at the feeder but require regular maintenance to prevent transponder failures that leave individual sows without feed access. Daily welfare checks must include body condition scoring and wound assessment across all group members.