Dissipation of heat from standing horses exposed to ambient temperatures between −3°C and 37°C

Abstract

1. 1. The aim of this experiment was to study how the rates of evaporative and the rate of non-evaporative heat loss from horses were influenced by short-term exposure to different ambient temperatures between −3°C and 37°C. 2. 2. The measurements were made in a climatic chamber on five horses at six different temperatures −3°C, 6°C, 15°C, 20°C, 30°C and 37°C. 3. 3. In ambient air temperatures below 20°C the rate of evaporative heat loss was almost constant. The rate of evaporative heat flow showed a pronounced increase above ambient temperatures of 20°C. 4. 4. The rate of non-evaporative heat loss was found to increase by 2.78 W m −2 per degree Celcius as the ambient air temperature decreased, as expected from the laws of physics.