Mice are the most widely used vertebrate in biomedical research; improving their welfare is both an ethical imperative and a scientific necessity for reproducible results.
Laboratory mice endure housing conditions far below their behavioral needs. Barren cages cause stereotypies — repetitive movements that indicate chronic frustration. Social isolation triggers anxiety and depression-like states measurable by standard assays. Procedures including injections, surgery, and blood sampling cause acute pain. Without adequate refinement, suffering is both ethically unjustifiable and scientifically counterproductive, as stressed animals produce unreliable data.