Page 109 - Speedhorse August 2018

means a total collapse, and this condition is more life threatening. With heat exhaustion, the horse will be very hot, but with treatment you could expect to be able to reverse and revive him. Whereas in heat stroke, the horse is in imminent danger of dying.
COOLING A HOT HORSE
After exertion, it is important to cool the horse quickly, especially if he is extremely overheated. “Air movement, cooler air mass with misting fans, etc., makes the horse much more comfortable than hosing him down or splashing him with ice and water. But if he is dangerously overheated, you need to use cold water on him,” says Allen. “We know now that putting cold water on the horse’s large muscle masses doesn’t cause any muscle prob- lems. People always used to be very cautious about that, but we proved in Atlanta that we could use ice water over the large muscles without causing harm,” he says.
“When the temperature of a horse gets up around 104 or 105, he should be washed down with water, and have it scraped off since the body will heat the water quickly,” says Allen.
The fastest way to cool an overheated horse is with cool/cold water, applying it over the body, especially on areas where the blood is near the skin surface such as the neck, chest, belly and legs. The veins under the skin on a hot horse will be standing out prominently, bringing overheated blood to the surface for cooling.
“You can’t just put the cold water onto the horse. You also have to scrape it back off because it heats up immediately, creating
a layer of insulation that slows the cooling process,” says Foss. “It works best to put
cold water on, scrape it off and put on more. You can readily feel that it warms up, so you scrape it off, taking the heat with it,” he says.
“Cool to cold water works well. There is still some controversy whether to put water over the horse’s back and rump. There’s
the old belief that cold water over the large muscles of the hindquarters or over the back might cause the horse to tie up, so most people tend to be careful with that. If we do use water on the horse’s back, we often apply it with a damp sponge rather than pouring it on. But over the horse’s sides, neck and legs, we apply lots of water,” Foss says.
“In hotter climates, people often add alcohol to the cold water to enhance evaporation, add- ing about a pint of alcohol to a gallon of water. You can also use ice water. If you think the horse is severely overheated or has heat stroke, take
his temperature. This will also let you know whether you are bringing his temperature down. Continue taking his temperature every five or 10 minutes. Stop cooling the horse when his temperature gets down to about 103 degrees
Horses can lose a fair amount of weight during transport, mainly from dehydration. Stopping to water them during transport or hauling them in the early morning when it is cooler can prevent heat stress.
because you don’t want to chill him.” If you keep cooling him too much and he starts to get colt, you can cause muscle cramping.
Some people walk the horse slowly around in a circle in between water applications to help provide more air flow around the body and to allow any breeze to hit both sides of the horse. Gentle exercise also helps the circu- lation continue to bring overheated blood to the skin surface for cooling.
“Use common sense. If the horse is over- heated when his workout is ended, try to get
him in the shade, take off all tack, and use lots of water. If your water supply is limited, use a sponge to put it on and wipe it off, so you aren’t losing a lot of water. If the horse is overheated, he should not return to work that day even if he’s cooled out,” says Foss. If he was severely overheated, he may need several days to recover.
Check with your veterinarian. “Heat stress can trigger other problems, including lamini- tis. We don’t always know how hot the horse actually got or how stressed he was, or how much damage might have been done.”
HOW THE BODY TRIES TO KEEP WITHIN A SAFE TEMPERATURE RANGE
In the horse, sweating is the primary mechanism of cooling. “Horses are very efficient
at sweating,” says Allen. “They can dissipate heat via radiation if the outside temperature
is cooler than the body. They can also pant, but this is the least effective of all their cooling strategies, especially since the horse must breathe through his nose rather than his mouth. Unlike the dog that can open the mouth and pant, the horse doesn’t have that option. The air must move through the upper airway, which is separate from the mouth,” explains Allen. The horse just breathes faster, to create more air exchange via the lungs.
The way we can help the horse most is to first not let the horse get so hot, and second, assess the horse’s temperature so we can realize when there is a problem. Third, we can put cool water on the horse, and take it back off again, taking heat with it.
Normal temperature for a horse is somewhere between 98 and 100 degrees. “A horse with a rectal temp of 102 to 103 after working is not in trouble. He just needs to be walked around and given the occasional sip of water, and some washing down with cool water. You don’t need to take extraordinary measures at this temperature because it’s normal for a horse to heat this much while working,” says Allen.
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EQUINE HEALTH