Dissipation of heat from standing horses exposed to ambient temperatures between -3 degrees C and 37 degrees C

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 degrees C and 37 degrees C.2. The measurements were made in a climatic chamber on five horses at six different temperatures -3 degrees C, 6 degrees C, 15 degrees C, 20 degrees C, 30 degrees C and 37 degrees C.3. In ambient air temperatures below 20 degrees C the rate of evaporative heat loss was almost constant. The rate of evaporative heat Row showed a pronounced increase above ambient temperatures of 20 degrees C.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. (C) 1997 Elsevier Science Ltd.