Pigs are among the most intelligent domesticated animals, with cognitive abilities that challenge the justification for many standard intensive farming practices.
The cognitive sophistication of pigs makes the barren, crowded conditions of intensive farming particularly troubling from a welfare perspective. Intelligent animals with nothing to do and nowhere to go develop profound behavioral pathology. Pigs that demonstrate optimistic cognitive bias — exploring novel situations without excessive caution — are measuring as experiencing positive welfare. Their capacity for empathy means that stress in one individual can spread through a group. High welfare pig farming must provide cognitive challenge and environmental richness.