The use of rugs on horses is often welfare-appropriate but can also cause harm through overheating, pressure sores and restriction of natural movement. Evidence informs rug decisions.
Over-rugging is arguably more common than under-rugging in companion horses and causes genuine welfare problems including hyperthermia, inability to thermoregulate and restriction of normal coat-raising behaviors. Evidence suggests horses manage cold efficiently through their coat and metabolic heat production. Rug decisions should be based on the individual horse, clip level, shelter availability and weather rather than owner perception of cold.