Transporting laboratory animals between facilities, suppliers, and research sites causes significant acute stress and can compromise both animal welfare and scientific data quality.
Transport is an underappreciated source of welfare harm in laboratory animal research. Animals experience multiple simultaneous stressors they cannot escape or control, driving acute stress responses measurable in physiology and behavior. Research conducted on recently transported animals may produce confounded results as transport stress alters immune function, reproductive hormones, pain sensitivity, and behavior — undermining the scientific validity of experiments conducted without adequate acclimatization. Regulatory frameworks acknowledge transport as a welfare concern but minimum standards leave significant room for improvement. Shipping live animals long distances when local alternatives exist is difficult to justify ethically, and the scientific case for longer acclimatization periods is strong.