How to Recognise & Deal With Heat Stress in Horses
The image of buying sunscreen for your horse at first might seem pretty surreal.
Unfortunately, the same blazing heat that causes us to feel dizzy and our skin to peel also has its fair share of problematic effects for our horses - the most important of these being heat stress.
As The British Horse Society have advised: “Our message is simple – horses need suntan cream and shade too. Owners need to be extra vigilant during a heat wave.”
So Country & Stable have decided to gather some helpful tips on safeguarding your horse in the sweltering summer heat so that you can recognise & deal with heat stress in horses.
What is heat stress?
Heat stress normally occurs just after an intense period of exercise, as the large muscle mass of horses has built up a great amount of heat.
Usually, sweating brings the body temperature right down, but if it’s scorching and the atmosphere is humid then this natural cooling effect isn’t effective - as sweat keeps pouring out, your horse starts to lose all-important water and electrolytes.
Without launching into a biology lecture, you lose fluids first from the bloodstream. After this supply is outrun, liquids are drawn from the inside of cells and this spirals into severe phases of dehydration.
Symptoms of heat stress in horses:
You should be able to spot the symptoms of heat stress after a heavy day’s training but it can occur in some unexpected places too, like stuffy, unventilated stables and horseboxes. The unsettled signs you should be looking out for include:
if your horse looks deflated, lethargic or has lost all energy to move around
unusually rapid breathing, approximate 60 breaths per minute
have a body temperature over 103.5 F
occasional spasms of the diaphragm or “thumps” caused by loss of fluids
an irregular pulse
No interest in food or water
If in doubt, we recommend Equus Magazine’s quick physical tests for dehydration that you can perform yourself: the skin-pinch and the pink-gum tests. If you pinch your horse's skin and it takes a few seconds or more for the skin to flatten smoothly out again, then something might be up.
Similarly, if you press softly on the gums just above the incisors and it takes longer than a few seconds for the capillaries to flush pink again, then start our cooling down measures.
The uncomfortable truth is that the failure of these internal systems can lead to heat stroke, muscle cramps, altered gastrointestinal functions and major damage to the kidneys, liver and lungs.
Tips for cooling your horse off:
As soon as you notice the tell-tale signs of heat exhaustion, you should call your vet and if possible get them to come and examine your horse.
In the meantime, there are a few things you can do to help your horse cool off. Firstly, bring riding to a complete finish and move to a cool, shaded part of the field, then work through our basic rules:
keep your horse walking to maintain circulation
remove sweat from the horse’s body as layers of perspiration stops heat from escaping
allow them to drink as much water as they like to replace lost fluids
shower your horse with cold water or apply ice packs to head and leg muscles
continue to monitor temperature
As you can imagine, heat stress mostly crops up after a strenuous day of gallops and fast trots, so before you set out for the afternoon try and follow our top preventative tips:
- According to Sharon J Spier, Professor of Equine Medicine at University of California, always check the day’s “heat index” and see how it might affect your training regime. Her rough guide is as follows:
- less than 90 F: Fine to ride normally as long as you cool down at intervals
- 90–100 F: Proceed with caution as heat stress is likely with strenuous exercise
- 101–129 F: Heat exhaustion risk is high, so time your training with cooler, breezier times of the day and avoid any intense activities
- above 129 F: A danger zone where risk of heat stroke is high. Reschedule your routine for another day.
Give your horse a relaxing ‘pre-cooling’ shower before launching into a day of riding
Always take enough water for your trip (obvious one, but absolutely essential)
When taking long journeys, horses should be given regular breaks from the heat of the horsebox. You can also try installing air conditioning too.
Higher factor SPF and waterproof horse-friendly sun creams are recommended - some products will even contain UV filters perfect for horses with sensitive or allergic skin.
If your horse is bothered by flies in the summer and requires a fly sheet or rug then ensure you get one that offers UV protection as this can help protect them from the sun. However, bear in mind that even a thin fly sheet can trap heat underneath so in really hot weather can be more of a hindrance than a help.
If you have any experiences of heat stress or useful tips we haven’t included, then please get in touch on Facebook and tell us about them!