Guinea pigs remain widely used in immunology and toxicology research and require welfare standards addressing their complex social and environmental needs.
Laboratory guinea pig welfare has improved through recognition of their social needs and adoption of group housing. However, the isolation, handling stress, and barren environments common in research settings continue to cause welfare harm. Replacement of guinea pig sensitization tests with validated in vitro alternatives represents one of the most successful applications of the 3Rs principle to reduce animal use.