Pigs are among the most cognitively sophisticated of all farmed animals, with intelligence comparable to dogs and some primates. Understanding pig cognition strengthens the ethical case for higher welfare standards in pig production.
Pig cognition research has transformed the scientific understanding of what pigs can experience and, consequently, what constitutes adequate welfare. The finding that pigs in barren environments show pessimistic cognitive biases — essentially a depressive-like state measurable objectively without anthropomorphism — provides compelling evidence that enriched environments produce not merely different behaviour but different subjective states. Their capacity for emotional contagion means that welfare harm to one pig in a group creates distress in observers — a welfare multiplier effect that makes high-density, poor-welfare housing even more damaging than it might appear when only focusing on directly affected individuals. The cognitive gap between what pigs are capable of experiencing and what standard commercial housing typically allows them to experience is substantial. Social complexity, problem-solving, play, and exploration are all within pig cognitive repertoire but are largely absent from barren commercial housing. Research consistently shows that cognitive stimulation through enrichment, stable social groups, and positive human interaction produces measurably better affective states across all welfare-relevant indicators.