Global warming and heat stress in horses

The maximum daily temperatures are climbing globally, and stable management approaches may have to be changed

- Dr Mac

It is a good time to learn how to recognise the signs of heat stress in horses, and also to understand how to restructure stable management to keep horses cool at midday. In horses, as in other warm-blooded mammals; the body temperature is measured rectally and varies between 37,5°C and 38,5°C throughout the year.

Scientists have described the optimal range of daily temperature for a specified species as the ‘thermoneutral’ range. For horses, this was calculated at between 5°C and 25°C . However, it varies according to breed and conformation.

For instance, Arabian horses were line-bred over several thousand years to function well in the hot deserts of the Middle East and North Africa. In contrast, breeds like the Iceland pony have been selected for their ability to survive ice and snow. Their conformation is different. The Arabian is long-legged and lean with little fat, so that it stands high above the heat-reflecting desert sand. Its coat is fine and the sweat evaporates fast.