Pigs are increasingly used in biomedical research as human analogues, but their high intelligence and social complexity make standard laboratory housing deeply problematic.
Pigs are among the most cognitively and socially complex animals used in research. They form strong social bonds, demonstrate empathy, play extensively, and suffer acutely when isolated or denied environmental complexity. Housing pigs individually in bare metal pens — still common in many facilities — causes measurable psychological harm. Refinements including paired or group housing, rooting substrate, outdoor access where possible and environmental enrichment reduce suffering without compromising experimental validity. Replacement alternatives including organoids and in vitro cardiac models are advancing rapidly and should be accelerated.