Q: What is a thermal-neutral temperature?

A: A thermal-neutral temperature, or some people refer to it as the critical temperature, is an ambient temperature at which a horse doesn’t have to expend energy to maintain its own body temperature. That means the horse doesn’t need additional calories to stay warm.

You can have temperatures that go above the thermal-neutral zone, obviously when it’s really warm outside, or temperatures that go below when it’s cold. If it’s above the thermal-neutral zone, the horse expends energy dilating its blood vessels or sweating to cool itself. When temperatures are cold, as in during the winter, the horse has to change its metabolic processes to produce heat and grow a hair coat.