I started to write an educational article all about the pretty amazing, nay incredible, thermoregulatory mechanism of horses.  It included information about the four main components of this system that has kept horses healthy and alive for several millennia now, whether they live in equatorial or subarctic regions.  It was going to be extremely informative and eye-opening to those that are not that well read on a rather important subject in regard to good horse husbandry. I had even given it a rather natty, quirky title to catch your attention.  But, when I realised I´d covered four pages of A4 and was still far from finishing, I chucked it into the virtual trash.  The facts are out their if you care to look for them.  Here is the nutshell bottom line;

Temperatures fluctuate continually in a natural environment.  In a stall they remain constant.  Movement is constant in a natural environment.  In a stall it is completely restricted.  A horse is perfectly adapted to deal with continual fluctuations in temperature. They either stand still, or move (!) whilst the incredible filament muscle system near the skin surface does it´s amazing work to regulate the body and maintain the internal temperature at 38ºC.  And they eat, 16 to 18 hours out of every 24 they eat.  This head-low posture, constant movement, constant intake of low-energy forage is what keeps them warm and healthy on cold days.  Any changes to body weight happen gradually and actively, whilst their stalled brothers will suffer sudden passive changes.  

Continual rugging causes atrophy to these tiny muscles.  Rugging prevents the growth of a winter coat and it´s ability to raise, lower and turn in different directions, so when the horse is ridden in cold temperatures he is at greater risk to get a cold.  Here in southern Spain, the temperatures can fluctuate between very cold and pretty damned warm in the space of a few hours.  A rugged horse will begin to sweat and can overheat.  When rugged no breeze can conduct the heat away.   Left to do it naturally, a horse will seek a windy spot and turn it´s hairs in different directions in order to dry the coat as quickly as possible.  

All my horses live out.  At best, the advanced level endurance competitors, get a trace clip when their winter woollies are particularly woolly and they are still training and competing.  After training they go and roll in the sand, they don´t get a shower, and their body temperature remains healthy.  If it rains constantly for 3 or 4 days, as it has a tendency to do here, they will get a no-fill waterproof rug put on just for that time.  What they always have is ad-lib hay and every paddock has a hard-stand, dry area so they can get their feet out of the mud.  There are natural and man-made shelters in their paddocks, yet in blazing sun or howling wind I rarely see them use them!

If you have no choice but to keep your horse stabled (!), consider the riding you do in the winter.  Keep it to warmer times of day. Don´t return with your horse heated.  Let them cool down gradually on the return from a trek or with a long walk-out session after school work.  Consider how you can place slow-feeding nets around the stall so they have a constant forage supply.  If your horse lives out, it will be so much happier being permitted to survive as nature prepared it to do so. 

(If you´d really like to know more, send me an email)