When lying by a pool is not on the agenda, H&H finds 
out how to get through
 a hot spell with your horse this summer

It’s a sure jinx to predict a heatwave. But when the mercury touched 25°C in April, the odds tumbled for Britain’s hottest ever summer.

We know that horses underperform in hot weather. The virtually invincible Valegro produced his worst result in the past five years at a sweltering Aachen Europeans (33°C) in 2014, where another star, Parzival, looked drunk. At the Barcelona Olympics in 1992, two horses collapsed after the cross-country.

So how should we care for our horses in such un-British temperatures?

1. Prevention is better than cure

The ideal is not to allow horses to get too hot. And if they do, to cool them effectively. Following Barcelona, the International Olympic Committee and FEI funded a research project into the effects of heat and humidity on horses. Dr David Marlin, who led the project, says: “Horses were finishing cross-country at Barcelona with temperatures off the range on the thermometers, over 41°C. It was a wake-up call ahead of Atlanta 1996 — the key was to learn what would be reasonable to ask of the horses given the conditions.”

The team developed an on-site assessment of the thermal load on horses — the Wet Bulb Globe Temperature (WBGT) index. This takes into account air temperature, humidity, sunlight and wind, to give a certain number. If conditions produce a figure above 28, horses are adversely affected, leading to falls and fatigue, and therefore the effort on the course must be reduced (by shortening the course, or removing jumps). If the WBGT exceeds 33, conditions are considered incompatible with safe competition. This system will be used at Tokyo 2020.

2. Don’t ignore horses that are turned out

It’s not just elite competition horses at risk during a heatwave; even horses out in the field can suffer.

A spokesman for the British Horse Society highlights the need for shade, water and suncream. “Horses are affected by the sun in the same way as humans — like pale-skinned and fair-headed humans, horses with pale skin and grey or white fur are most susceptible to burning,” she says.

“If your horse has pink — rather 
than brown — skin, they are particularly 
at risk. Muzzles are very sensitive, so apply 
a high-factor suncream liberally and regularly around that area.”

H&H vet Karen Coumbe urges owners to take action if a horse is looking uncomfortable out in the field, even at rest, during a heatwave.

“Take his temperature,” she says, singling out “black, hairy, overweight cobs” as the most susceptible. “Horses out in a field, provided they have some shade, are unlikely to develop heatstroke, but if they are exercising hard, then hot, humid conditions can be challenging. If his temperature is over 39°C, he’d benefit from some cooling; more than 40°C and he’s at risk of heatstroke. More than 42°C can be fatal.”

3. Know the signs of overheating

“A seriously overheated horse may not be sweating,” Karen cautions. “He could be so dehydrated he doesn’t have the resources to sweat. Horses with heatstroke can be agitated, wobbly, depressed and show signs of colic. 
The breathing may be inconsistent or rasping, the mucous membranes congested and he 
may have a weak pulse. If you see any of these signs, take his temperature, start cooling and consult your vet.”

4. Have water at the ready

“Aggressive cooling” should be used, where cold water — between 4-10°C — 
is poured on the horse, focusing on the main large muscle groups such as the quarters.

Karen has a few practical suggestions. “I’ve seen riders with little watering cans dribbling water down the horse’s neck — this is nowhere near enough water,” she says. “You need buckets of iced water, then ideally use big plastic jugs so you don’t waste water chucking it all over the place.

“Don’t apply ice packs directly on the 
skin, as it can cause thermal damage. Keep it simple — you need to cool the large muscles quickly. And move the horse to a shady area with a breeze. Misting fans are a marvellous luxury, if available.”

5. Keep horses moving

David advocates keeping the horse moving, as this increases the blood pressure (reducing the risk of collapse), and cooling the horse as fast as possible all over the body, because it’s the skin’s cooler blood that will go through the heart and into the muscles.

6. Suss out the tips and tricks that work for you

Irish eventing groom Philip Smyth Mua had his own little trick to keep horses comfortable after last year’s young rider Europeans, where it was 28°C. “I put a sponge in the freezer, and then popped it under the headcollar while I was walking horses off after cross-country.”

Liked this? You may also enjoy reading these articles…

7. Know the rules about hosepipe ban

In a hosepipe ban the use of 
a hosepipe “for the cleaning, maintenance and general wellbeing of any kind of animal is exempt from hosepipe ban rules”, due to animal welfare.

This means that bathing your horse, hosing down his stable or the lorry, and 
filling drinking troughs are still permitted under a ban.

In 2012 (when there was the last major hosepipe ban) there was also an official exemption to the restrictions on watering grass, “if it is used for sport, where this is required in connection with a national or international sports event”. So we shouldn’t fear rock-hard going at competitions.

Read the full article about surviving a heatwave, plus more about summer horsecare — including dealing with laminitis and sweet itch — in this week’s issue of Horse & Hound magazine (1 June 2017)