Transport is one of the most significant welfare challenges across species in both farm animal and companion animal contexts. Understanding the physiology and behaviour of transport stress informs better practices.
Transport stress affects animals through multiple simultaneous mechanisms. Unfamiliar environments, sounds, vibration, novel conspecifics, and temperature extremes all activate stress responses. The inability to control any aspect of the environment amplifies fear responses. Physical exertion during loading and unloading at each end of journeys adds physiological stress. For food animals, extended fasting periods begin before loading and continue through transport, adding metabolic stress to fear. Companion animals transported in cargo holds face temperature extremes, noise, vibration, and complete social isolation in the absence of reassuring human contact. Improving transport welfare requires attention to vehicle design, driver training, journey duration limits, and pre-transport fitness assessment.