Snug as a bug?

Understanding the body’s natural temperature mechanisms can help us get rugging just right, explains Rick Farr MRCVS

- Rick Farr MRCVS

“The average horse can live unrugged in temperatures down to 5°C”

AUTUMN is approaching; the evenings are a little cooler and rain is starting to come in sideways, sending a chill down your spine.

With winter looming, it’s time to reach for that massive, all-inone heavyweight rug to keep your horse nice and toasty. Or is it?

It is important to consider how nature has equipped different species to cope with changing seasons. The horse has developed some unique tolerances to cold and wet weather – conditions which may make us shudder but rarely bother our equine counterparts.

Horses are found throughout every climate on the planet, from the sub-zero north to the tropics and arid deserts. Their adaptations to remaining within their specifi c thermal neutral zone (TNZ) are impressive.

The term TNZ describes the ambient temperature range at which the body needs to make no additional physiological effort to warm or cool itself. Humans have a TNZ of roughly 18 to 30°C; in other words, in this zone you could stand naked and still maintain your internal core temperature without too much issue.

Horses, however, have a much larger TNZ. The average adult horse can quite happily live unrugged in temperatures down to 5°C, but how many times have you grabbed that heavyweight rug when it has been a balmy 10°C?

Right: a hand on your horse’s shoulder gives a rough guide as to whether he is too warm

BALANCING ACT