Outdoor pig production systems provide environmental enrichment and behavioral opportunities but face welfare challenges from parasites, weather extremes, and predation.
Outdoor pig welfare generally exceeds indoor intensive welfare on behavioral dimensions — outdoor pigs can root, wallow, explore, and exhibit natural social behaviors that are frustrated in concrete housing. However, outdoor systems present their own welfare challenges. Parasites including Ascaris worms and mange mites are more prevalent and require active management. Summer sunburn causes pain in fair-skinned breeds without shade or mud access. Extreme cold can compromise welfare in poorly designed outdoor systems without adequate shelter. Predation in some regions causes acute welfare incidents. Overall, well-managed outdoor systems represent a welfare improvement over intensive indoor production when these challenges are addressed.