It is summer and many of us ride during peak hours.
Some of us even event during these hot and humid days.
For me, there is nothing worse than watching an unfortunate horse being demanded to perform in hot/humid conditions without adequate prep, proper cool down or ‘danger sign’ recognition from his owner.
… Makes me crazy.
So, after being prompted by a kind reader (thank you) and after discovering a handy and inexpensive product at the Horse Expo, I decided to write about this pet peeve of mine.
FIRST OFF, THE BASICS…(elaboration later)
The best way to cool down an overheated horse is to:
1) Get them into the shade (remove them from radiant heat gain)
2) Let them drink tepid water – add electrolytes or Gatorade (hydration)
3) Cold water baths (conductive heat loss) starting with feet/legs
*the most effective areas to cool a horse are the poll, jugular vein, femoral and carotid artery…
4) Get a breeze going – fans/air movement (convective heat loss)
An overheated horse is an unhappy horse. He needs to be cooled down quickly to avoid medical complications. Follow these steps to help him:
• Move him to a shady spot.
• Take his temperature, heart rate and respiration rate.
• Compare all three rates to his usual ones and call your vet is they are abnormally high.
• Set up fans at a safe distance from the horse if you have them available.
• Hose cold water on his belly and underside.
• Hose cool to tepid water over his back.
• Never pour or hose very cold water over large hot muscles or his back.
• Scrape the water off with a sweat scraper as you go.
• Offer the horse a few sips of tepid water.
• Take his temperature again in 10 minutes. If it isn’t dropping, call the vet immediately.
THE SIGNS…
(from Horse Owner’s Veterinary Handbook, 2nd Edition by Giffin MD and Gore DVM.)
Heat Stroke is a dire emergency! Horses sweat for a reason. As the sweat evaporates, it removes heat as well. When it is very humid, this process can be inhibited. So heat stroke is more common on humid days because the horse cannot cool off properly.
Symptoms include: A sudden increase of sweating, elevated rectal temperature, fast heart rate, flared nostrils, rapid breathing. If breathing is higher than the heart rate, the horse is severely overheated. Muscle cramps, tremors, stiffness, and not wanting to move, tying up, depressed, weak, not wanting to drink water, and usually dehydration is also a problem.
CALL THE VET! Vets need to be involved during this process. Until your vet gets there, you can begin cooling your horse off by moving the horse into the shade and spray repeatedly with cold water. Apply alcohol sponges to the neck, flanks, and lower extremities. Set fans up on the horse. Allow the horse to sip water as he begins to become interested in drinking. The vet can administer enemas and IV Fluids to help the horse come back under control.
OTHER THOUGHTS
1) Some vets recommend alcohol baths saying that It evaporates quickly, and pulls heat away from the horse’s body much faster than water alone does.
2) It is important to scrape away cooling water applied to any overheated horse because this will pull away the heat stored in that water.
3) When using cold water, it is always best to start at the legs and move upwards while scraping away the excess water as you go. Some vets say to use only tepid water while most say cold water is best.
Clearly, applying water and removing it – is important…
4) Putting ice on the poll, jugular vein, carotid artery and femoral artery (inside of rear leg) will cool the horse quickly.
5) A horse can swallow 4 gallons of water before extending the stomach so give him a bucket of water, not just a sip. Add electrolytes to the water as long as he is willing to drink it. Use Gatorade if you have it.
6) Don’t overwork your horse in heat and humidity.
7) Prep/train your horse for the heat – just like humans need heat training.
MYTHS
(From: Managing Heat Stress in Horses: Kevin H. Kline, PhD, Professor of Animal Sciences)
1. “Never let a hot horse drink more than one or two swallows of water at a time.”
2. “Never give ice-cold water to a hot horse – either inside or out.”
3. “Never let a hot horse cool out without a blanket or sheet.”
4. “Never let a hot horse cool out in a drafty area.”
By far, the most important mechanism for heat dissipation in horses is evaporation. Conversion of the water in sweat (or other sources of water placed on the horse’s hot skin) into gas consumes heat and cools the horse’s skin. During and after exercise, the horse’s skin is laden with dilated capillaries carrying overheated blood from the body core. The blood in these capillaries is cooled to help maintain a reasonable body temperature that will allow the horse’s nervous and muscular systems to function normally. Even a normally hydrated horse with no inhibition of evaporative cooling that is exercising in a hot and humid environment may achieve a rectal temperature in excess of 104 degrees Fahrenheit. Disallowing the adequate water consumption that can be used for sweating, or blocking the evaporation of water from the skin using a blanket, are very bad ideas during hot and humid conditions. These practices can result in a horse’s body temperature spiking into a dangerous range of up to 107 or 108 degrees Fahrenheit (heat stroke). Although allowing a hot horse to consume unrestricted amounts of water may lead to problems such as colic due to hyperdistension of the stomach, it should be realized that a typical horse’s stomach can hold between 2 and 4 gallons of fluid without being distended. So, even though a horse’s stomach is small compared to other animals of its size, one or two sips of water at a time is overly restrictive when the hot horse is rapidly losing water trying to keep itself cool.
Statement #2 above has been the source of some controversy over the years because of the belief among certain horse trainers that ice cold water placed on a hot horse’s body will “shock” the horse’s thermoregulatory system into shutting down blood flow to the skin. This belief has been found to be wrong. Extensive research conducted during 1995 at the University of Illinois and University of Guelph and at the 1996 Olympic Summer Games in Atlanta proved conclusively that horses working under hot and humid conditions were better able to maintain core body temperature within an acceptable range or even reduce it during rest periods after intense phases when ice water baths were used. Liberal application of icy cold water to overheated horses helps to dissipate heat not only by providing more water to evaporate from the skin, but also by direct conduction of the horse’s body heat into the water which runs off the horse, carrying away excess heat in the process. According to University of Illinois researcher Dr. Jonathan Foreman, “In our treadmill simulations of C Halt (a rest period during a phase of the equestrian competitions at the Olympic games), cold water baths were used with significant decreases in core temperatures and heart rates. No adverse clinical effects were apparent during the remainder of Phase C trotting or after exercise. Horses actually trotted more freely after bathing stops.”
*(from me) Since this article was written, it has also been discovered that more focused cold water (ice) placed directly on the carotid and femoral arteries, the poll and jugular vein are very beneficial. In fact, Texas A&M is now requesting air weave blankets with pockets to hold ice over these areas as well as the back and large rump muscles.
Another practice that makes little sense physiologically is preventing access to
moving air during hot and humid conditions. During the 1996 Atlanta Olympic
Games, 85 misting fans were placed at shaded recovery areas throughout
various phases of the equestrian courses to allow these elite athletes to stabilize
and lower their body temperatures. Regular dry fans work to both increase
evaporation, and also dissipate heat by the cooling process known as
convection. Misting fans take advantage of the additional cooling property of
blowing water onto the horse that is in the process of changing from liquid to gas.
The shaded areas guard against additional heat load through solar radiation.
Although radiation of heat from the horse’s body into the atmosphere is a
potential mode of heat dissipation, it most often works in the opposite direction
during sunny days, with horses (especially dark ones) gaining radiant heat from
the environment
PRODUCTS
** EQUI COOL DOWN PRODUCTS. I highly recommend them. I don’t think your horse should be ridden in this kind of hot weather, but if you need to cool one down – or an older horse…. or a sick horse, these products are terrific. Really.
I use the human products all the time. I love their stuff and it WORKS (I practically live in their neck towels…). You wet the cloth and snap it – to get the cool. It stays cool, even during really hot day, for the longest of any product out there (imho). No affiliation.
I thought this was an interesting concept from the UK. The developer spent time racing in Dubai and feels that alcohol or – drawing the heat out – is the ticket.
It reminds me of external anti-freeze for your horse. I think it is fast and furious…
From the website:

Equinice products
Equi-N-icE works by drawing heat out as opposed to other products that work on driving cold in.
Equi-N-icE requires No refrigeration, is not messy, needs no mixing, has no unpleasant smells.
The treated area will drop by 10-15°C and stay that way for up to 2-3 hours.
Once used the Equi-N-icE Bandage can be washed and reused by adding enough ready mixed Coolant to make the Ice bandage damp and replace in the re-sealable pouch until needed again.
The Coolant is supplied in correct concentration for direct application for ease of use and it is non irritant to skin.
3) ICE BONNET
Simply put, this is the right idea but not as inexpensive nor as quick and easy as the RES ER VEIN/ARTERY COOLER.
However, it has a poll cooler, which is nice. And, it looks more sleek.
To me, the downside is that you have to have the ice packs with you in order to make it work. If you left them at home, you are out of luck.
The concept is to have the ice packs cooled and ready to go (like what you would put in a lunch box or a frozen shipping container). Then, you insert the ready-made packs into the bonnet and neck cooler.

Ice-Bonnet cooler. The idea is to cool the poll and jugular. The sleek ice-packs insert into the neck and poll devices.

Great article keep it up!
Paula, that’s under “Myths,”
If whoever wrote this would email me. I’d like to talk to you about the possibility of being a guest on a podcast…but there are no vina-fides attached. So email me if interested.
Are you kidding me? A few sips of tepid water? That horse needs as much water as it will drink no matter what the temperature of the water. Drinking is the MOST essential way to cool a hot horse, ask any endurance rider, they will tell you to never, ever restrict water consumption. Tepid , hot cold whatever, let them drink and drink, that will cool them and hydrate them. The most important thing is hydration. It is an old myth that you should restrict water consumption to a hot horse, old myths die hard, but this one is dangerous.