Environmental enrichment for laboratory animals improves welfare and can also improve research quality by reducing stress-related variability in experimental results.
Laboratory animal enrichment has the unusual property of benefiting both animal welfare and research quality simultaneously. Chronically stressed animals show elevated baseline corticosterone, altered immune function and abnormal behavior — all of which introduce variability and artifacts into experimental results. An enriched animal living in appropriate social groups with stimulation and control over its environment is both happier and a better research subject. The regulatory direction is clear — social housing requirements for social species and enrichment requirements are expanding. The remaining challenge is implementing enrichment thoughtfully so that it improves welfare without confounding the specific variables being measured in each experiment.