How should I cool out my horse in the summer?
Jan. 2000

Pat Thrasher

Email: gbexcel@aol.com


There was a *lot* of work (research and experimentation) done in 1995/1996 in 
anticipation of the 1996 Atlanta Olympics on cool-down and recovery rates and 
so forth for horses, because everyone was so worried about the eventers in 
the Atlanta summer heat. Many of the various horse magazines carried articles 
summarizing this research (Equus, Practical Horseman, The Horse all did), but 
in *very* brief:



There are two separate issues:  "warm-down" from exercise, where the lactic 
acid buildup in fatigued muscles is dispersed, and cooling off, which is 
bringing the horse's temp. down to a normal range following exercise. The 
warm-down is best accomplished by following the old rule: walk the first and 
the last mile of a trail ride; or, if you are schooling in an arena, figure 
on finishing your school by jogging around on a loose rein for a few minutes, 
then walking ditto; then dismounting and walking with Hoofer for a few 
minutes, loosening the girth and continuing, and finally going back to the 
barn. This allows the waste products of exercise to be moved out of the 
muscles into the bloodstream where they can be dealt with by the kidneys and 
liver and so forth.



The other, issue, heat buildup, is a completely different issue. Basically, a 
hot horse needs to be cool, and a thirsty horse needs water. Keep in mind 
that it is perfectly normal for a horse exercising hard on a hot summer day 
to run a rectal temp. of 105 or even 106. If he is fit, sweats well, and has 
access to water, such a temp isn't dangerous. However, once he stops working 
and goes through his warm-down, he *needs* to be cooled off. The best way to 
do this is to sluice him repeatedly with cold water and scrape immediately. 
If you don't scrape, the water acts as a blanket and actually holds heat. 
Major points for cold water are the legs, throat/neck, and head (where major 
blood vessels run close to the surface), and the hindquarters and back, where 
large muscles dissipate heat well. Keep sluicing and scraping until the water 
comes off not much warmer than it went on. Meanwhile, let him drink, he needs 
the water. Especially let him drink *during* exercise if at all possible; if 
that isn't practical, don't withhold water once you're done. Put a bucket of 
water in the wash stall and let him drink out of that, or out of the hose 
(BTW, remember to drink yourself, if he's hot and needs water, so do you 
:-)). Chances are he'll suck down about half a bucket right off, and then sip 
along at it or the hose. The cooling process is much accelerated by doing all 
this at least in the shade, if not in the barn.



If your horse is *in distress* from heat-- not sweating, coat harsh, 
twitching, kicking, acting weird, spiking a temp-- he is in the first stages 
of heat exhaustion/stroke. He needs *ice*. Under his tail, on his head, under 
his jaw, where the big blood vessels can carry cooler blood directly to his 
brain and other systems. This is a moderate emergency. Take his temp every 15 
minutes and if it isn't coming down, call the vet. Get him out of the sun, 
and get him wet as above immediately. Keep applying ice and water. Don't walk 
him or do anything except concentrate on getting that temp down, and *don't* 
give him electrolytes. Let him have plain water if he wants it. Once his temp 
is down and he's cool, watch him carefully for a while, and be prepared for 
another episode, or for colic, tying up, whatever-- heat exhaustion/stroke is 
a systemic problem and can spawn other problems.



Anyway, that's a very brief summary of the conclusions drawn by the teams of 
vets who worked on these issues for the Olympics. After reading up on all 
this, I ditched the conventional wisdom of centuries about cooling off and 
water and all-- and I have to say, my horses have done really well the last 
few summers, seemed to be a lot more comfortable, and have had zero problems. 
If you want a *really* exhaustive analysis, ask an experienced endurance 
trail rider, they really have the goods on this stuff.

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