Since June 24th, France has been gripped by an early heatwave that is not only making riders sweat but is also leading to the cancellation of numerous equestrian competitions. In the United Kingdom, British Showjumping and British Dressage have had to suspend their events, which were placed under red alert. All this because of a sneaky enemy, dreaded every summer: heatstroke in horses, this invisible danger capable of ruining a performance and even endangering the lives of our mounts.
Heatstroke in horses: a silent and formidable enemy
For horses, which generate an impressive amount of heat during exertion, regulating body temperature is a challenge. Sweating is their primary means of cooling. But when the air is humid and the ambient temperature easily exceeds 30°C, sweat no longer evaporates properly. The result? The cooling mechanism breaks down, the internal temperature rises dangerously, and heat stress sets in.
To give you an idea, a horse's normal temperature ranges from 37.5 to 38.5°C. A reading above 40°C indicates severe hyperthermia, and if it reaches 41°C, it's a life-threatening emergency. At this stage, the organs suffer rapidly, and the horse can die quickly, especially after strenuous exercise during a heatwave.
Recognizing the warning signs of heatstroke in horses
Heatstroke doesn't give warning; it strikes quickly. The signs are sometimes so subtle that inexperienced riders might miss them:
- Rapid and shallow breathing, even panting like a dog.
- Profuse sweating followed by a sudden cessation of perspiration is not a relief, but an alarming sign.
- Marked dejection, unsteady gait, disorientation indicating neurological damage.
- Dark red mucous membranes, elevated resting heart rate.
- Body temperature above 40°C and refusal to hydrate.
It is best to recognize these signals early in order to act effectively.
How to act quickly to save a horse suffering from heatstroke
The key word here is urgency and immediate action. "Waiting for it to pass" is not an option when a horse shows these symptoms. Any delay can prove fatal.
The recipe for a quick rescue? Stop all exercise, move the animal to the shade and a draft. A cold shower, preferably continuous, will lower its temperature rapidly. Contrary to popular belief, cold water doesn't cause thermal shock but saves lives.
The horse should be sprayed, the warmed water scraped off with a heat knife, and then the process repeated continuously. Misting and moistening sponges on areas with large blood vessels, such as the neck and inner thighs, also help speed up recovery.
Hydration is essential; provide fresh but not ice-cold water, with added electrolytes if the horse tolerates it. Most importantly, a veterinarian must be called immediately if the temperature does not decrease or if neurological problems appear.
Why do equestrian competitions jump when the heat rises?
This isn't just a whim of the federation or an excuse to frolic between the jumps on a day off. During a heatwave, bringing together several horses under stress dramatically increases the risk of heatstroke. The French Equestrian Federation (FFE), the French Institute of the Horse and Riding (IFCE), and the FEI now impose strict protocols and strong recommendations to ensure equine health.
In the UK, the cancellations under red alert on June 24th and 25th demonstrated that when temperatures and humidity soar, it's best to know when to cancel. It's far better to reschedule events for cooler times or reduce the exertion than to risk the horses' lives.
A simple calculation that's quite alarming: add the temperature in degrees Celsius and the humidity level as a percentage to obtain a stress index. Below 130, the horse can still sweat effectively; between 130 and 150, it's best to slow down and monitor its activity; but above 150, especially with more than 50% humidity, it's a definite no-go—stop, rest is mandatory. For example, 33°C with 60% humidity gives an index of 93 + 60 = 153, which is definitely not suitable for work.
Prevention: the key to a peaceful summer
Knowing the dangers of heat stress in horses This is essential, especially for those participating in demanding endurance or show jumping competitions. Equip yourself with a heat knife, keep a bucket of water handy, and carefully note the weather conditions. A logbook is invaluable for your veterinarian to react quickly in an emergency.
Finally, you have to know when to say no. The true courage of a responsible rider lies in withdrawing when the horse's health is threatened. After all, cancelling a race today might mean a victory tomorrow.
For a more comprehensive exploration of the issues at stake prevention in competition or to find out how best to manage these heatwave episodes, don't hesitate to find out more.