Standard laboratory animal housing is often designed for experimental control rather than animal welfare, with barren cages that fail to meet the behavioral needs of mice, rats, and other research animals.
The assumption that enriched housing compromises research validity has been widely refuted by the scientific literature. In fact, stressed animals in barren housing may produce less reliable results due to the confounding effects of chronic stress on physiology and behavior. The primary barriers to better housing are cost, habit, and uncertainty about protocol changes. Institutional animal care committees and researchers working together can implement meaningful enrichment that simultaneously improves animal welfare and scientific rigor. Nesting material for mice is perhaps the single most cost-effective welfare improvement available.