Wallowing in mud is a fundamental thermoregulatory and comfort behaviour for pigs. Its systematic denial in commercial farming represents a significant and preventable welfare deficit.
The denial of wallowing to pigs, a behaviour so fundamental that it is used to regulate body temperature in the absence of sweating, is a pervasive welfare failure in commercial pig production. Pigs without wallowing access in warm weather experience thermal discomfort that escalates to heat stress; they also lose the parasite protection, skin conditioning, and positive emotional experience that wallowing provides. Outdoor systems with wallow provision demonstrate measurably better thermal welfare outcomes. Indoor systems are structurally unable to provide wallowing and must compensate through robust ventilation and cooling, which is often inadequate, particularly as climate change intensifies heat events. Consumer support for outdoor, higher-welfare pork production directly supports access to one of the most fundamental behavioural needs of the pig.