Unlike most farm mammals, pigs cannot cool through sweating and rely entirely on external means — wallowing, panting, and shade — making climate management a critical welfare responsibility in warm regions.
Pig heat stress welfare is a climate-linked problem that will worsen as global temperatures rise. Pigs denied wallowing access — the primary natural cooling mechanism — in warm conditions are physiologically constrained in ways that cause genuine suffering. Behavioral indicators including excessive panting, reduced activity, and crowding at cool spots indicate acute thermal distress. The mitigation is straightforward: cooling infrastructure including misting, fans, shade, and access to wallowing for outdoor pigs. But the economic incentive to under-invest in cooling in borderline temperature ranges means welfare standards and enforcement are needed to ensure consistent provision rather than crisis intervention.