Horse owners are routinely putting rugs (blankets) on their horses all year round. However new research suggests that certain types of rug could be causing them to overheat. It has become routine (and even fashionable) for many domestic horses to be rugged all year round – in fly-sheets, all-weather turnouts, stable rugs, fleeces or perhaps even a onesie. Rugs can be useful in protecting horses from biting insects and in adverse weather conditions; however, until now there have been very few studies on rugging at all and none on the effect of different types of rugs on a horse’s body temperature.