Heat stress in horses

As summer comes around, the temperatures are set to reach extremes. The hot weather along with the humidity can have a dramatic effect on the health of your horse and their performance if not managed correctly.

Due to horses being expected to perform at an intense level, there are a number of dangers in summer that can lead to serious health problems which include: high temperatures; lack of air flow; humidity; poor ventilation; dehydration; and extended periods in sunlight.

Signs of heat stress

Depending on the amount of exercise your horse does, heat stress could be a very real problem that needs to be monitored throughout the warmer months. Horse’s muscles transform their energy into movement, with some of this energy being lost in the form of heat. This heat they produce can climb quickly and without a way to disperse of it, they would more than likely overheat in a matter of seconds.

Fortunately, horses are able to stop themselves from overheating by increasing their sweat rate, moving more blood to the capillaries under the skin and increase their rate of breathing. However, if the weather is unbearable and too much for the horse, they may not be able to fully relieve all this extra heat that builds up which can lead to heat stress.

The most common signs of heat stress are:

• Sweating profusely
• No Sweating
• Rapid breathing – more than 20 breaths a minute
• Rapid heart rate – more than 50 beats a minute
• Dry and hot skin
• Unusually high rectal temperatures – greater than 38°C

Reducing the effects of heat

If you notice any of the above symptoms with your horse, you need to act immediately as heat stress can turn serious very quickly. Having a veterinarian examine your horse is important as they will be able to determine the severity as well as administer any medical treatment that may be needed.

Moving your horse to a cool, shaded area and using a sponge to with cold water to wash them down is a great start to combatting the effects of heat stroke. Make sure to target the insides of the legs and around the head and neck area with the hose/sponge as this is where the blood vessels are located near the surface.

More often than not giving the horse water and letting them rest in shade will bring all their vital signs back to normal. Encourage them to drink as much as water as possible by giving them the option of plain water and water with electrolytes.
Be sure to keep an eye on your horse over the next two weeks as horses that have seriously overheated tend to be more susceptible to overheating in the future. It is best to be cautious when it comes to horses and heat, therefore getting your vet to check your horse out for any complications is recommended.