Top Tips for Keeping Your Horse Cool in the Heat
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Top Tips for Keeping Your Horse Cool in the Heat
British summers are changing. Temperatures that once felt exceptional are becoming far more common and many UK horse owners are now managing prolonged spells above 28 degrees. Here is everything you need to know to keep your horse safe, comfortable and well through the heat.
Understanding how horses handle heat
Horses cool themselves almost entirely through sweating. Unlike humans, who also lose heat through respiration, the horse's primary thermoregulation mechanism is evaporative cooling from the skin surface. In a hot environment, a horse working moderately can lose 2 to 4 gallons of sweat per hour.
The problem in the UK is humidity. High ambient humidity significantly reduces the effectiveness of evaporative cooling because sweat cannot evaporate as efficiently from the skin. This is why a muggy 25 degrees can feel more dangerous for a horse than a dry 30 degrees. Veterinary research uses a combined temperature-humidity index to assess risk, and the relationship between the two matters as much as the temperature reading alone.
Top tips for keeping your horse cool
A horse can drink 25 to over 50 litres per day in hot weather. Check troughs multiple times daily. Never add electrolytes to the only water source as some horses will reduce intake if they dislike the taste.
Consider stabling during the day and turning out overnight or early morning during a heatwave. If stabling during the day, ensure ventilation is excellent. A poorly ventilated stable can be hotter than the field.
Trees offer better shade than fixed shelters because one side is always out of the sun. Fixed shelters can be in full sun for hours. If your field has neither, daytime stabling with good ventilation is safer.
Focus on large muscle groups in the hindquarters, neck, and between the legs. Use a sweat scraper to remove heated water and reapply. If the hose has been in the sun, run it until the water is genuinely cool first.
The safest window is before 9am or after 7pm. Avoid peak heat between 11am and 3pm entirely during heatwaves. If your horse seems flat before you tack up, that is worth taking seriously.
Light-coloured fly rugs reflect heat better than dark ones. A wet fly rug has significantly increased cooling properties. Avoid heavy or poorly ventilated rugs above 28 degrees.
Horses lose sodium, chloride, potassium, calcium, and magnesium through sweat. Salt licks cover basic needs for light work. Horses in regular work sweating heavily benefit from electrolytes added to feed alongside plain water.
Pink noses, white blazes, and sparse coat areas are vulnerable to sunburn. Apply equine-safe factor 50 daily. Repeated excessive sunburn can indicate underlying liver disease. Mention it to your vet if it seems unusual.
Horses with Cushing's disease or abnormally thick coats cannot thermoregulate effectively in heat. Clipping is a welfare priority in summer. Consult your vet about the appropriate clip for your horse's condition.
Travel in the early morning and avoid peak traffic. Keep windows open for maximum airflow. Above 30 degrees, professional transporters in the UK cannot legally move horses. Apply the same principle yourself.
Horses who need extra attention in the heat
All horses are susceptible to heat stress, but some need closer monitoring and more conservative management during prolonged hot spells.
- Veteran horses regulate body temperature less efficiently and may not show obvious signs of distress until heat stress is already advanced
- Overweight horses generate more internal heat and have greater difficulty losing it through sweating
- Horses with Cushing's disease often have thick coats that trap heat and prevent effective thermoregulation
- Foals and young horses have less developed thermoregulatory capacity
- Horses with respiratory conditions including equine asthma are less able to lose heat through increased respiration
- Competition horses working at intensity in heat face the greatest cumulative risk, particularly on humid days
Know your horse's normal. One of the most valuable tools in heat management is familiarity with your horse's baseline behaviour. A horse that is quieter than usual, less interested in food, or reluctant to engage in ways that are out of character is worth investigating, even if no obvious signs of heat stress are present.
Recognising heat stress and heatstroke
- Excessive sweating disproportionate to work done, or no sweating when it would be expected
- Fast, shallow breathing or flaring nostrils at rest
- Elevated heart rate that does not return to normal within 20 minutes of stopping exercise
- Lethargy, reluctance to move, or reduced appetite
- Stumbling or unsteadiness
- Pale, dry or tacky gums rather than healthy pink and moist
- Skin tent lasting longer than 2 seconds when pinched
- Rectal temperature above 39.5 degrees Celsius at rest
If you suspect heatstroke: move to shade immediately. Apply cold water continuously to the whole body, focusing on large muscle groups. Use a sweat scraper to remove heated water and repeat. Do not cover with wet towels as this traps heat. Call your vet immediately. Heatstroke is an emergency.
"Missing a ride is far preferable to managing heat stress. If your horse feels lethargic before you even tack up, trust your instincts. No schooling session is worth the risk of a horse suffering in extreme heat."
Veterinary consensus, equine summer welfare guidance
A note on the cold water debate
There is still debate on yards about whether cold hosing can cause muscle cramping in hot horses. Current veterinary guidance from the RSPCA, Blue Cross, and equine veterinary clinics is unanimous: if a horse is overheated, cold water should be applied promptly and generously. The concern about cramping is not supported by current evidence.
The belief that leaving water on a horse will cook them is also an equestrian urban myth. Evaporation draws heat away from the skin. Apply, scrape, and reapply.
Frequently asked questions
Can I still ride during a UK heatwave?
At temperatures above 28 degrees, strenuous work is not advisable for most horses. Below that, early morning or late evening riding with reduced intensity is generally appropriate for fit, acclimatised horses. Above 30 degrees, avoid exercise entirely. If your horse seems flat or reluctant before you start, take that seriously.
Should I add electrolytes to my horse's water?
Only if you also provide a separate source of plain water. Some horses dislike the taste and will reduce total water intake if it is the only option. For horses in regular work or sweating heavily, electrolytes added to feed are often a better approach.
Is it better to stable or turn out during a heatwave?
It depends on the quality of shade and ventilation in each option. A well-ventilated stable with fans can be cooler than a shadeless field. A field with good tree cover can be cooler than a stuffy wooden stable. Assess both and choose what is genuinely cooler for your horse and yard.
Can horses get sunburnt?
Yes. Horses with pink skin, white markings, and areas with sparse coat coverage are most vulnerable. Apply equine-safe factor 50 sunscreen daily during hot, sunny weather. Repeated excessive sunburn can indicate underlying liver disease, so mention it to your vet if it seems unusual.
Sources: RSPCA equine summer welfare guidance; Blue Cross hot weather horse care advice; Bell Equine Veterinary Clinic; University of Minnesota Extension horse heat care guidelines; Horse and Hound heatwave advice; Country and Stable equine heatwave veterinary guidance.