How does the heat impact our horses and what can be done to mitigate any negative impact on horse health?

While we may not have seen the sustained scorching temperatures of last summer just yet, the UK is sure to get a least a mini-heatwave if not a longer spell of hot weather before autumn arrives. With that in mind, innovative equine health company Haygain examine how hot weather can impact horses and what owners can do to mitigate any negative impact on horse health. 




Just like people, horses will lose more fluids in hot weather and need to stay hydrated. There was an old horseman’s myth that a hot, blowing horse should not be offered cold water in case they colic. This has been thoroughly disproven, and horses should never be prevented from drinking water when it is warm. Ensure that horses have access to fresh and clean water at all times and check your water troughs are in good working order when the sun is beating down.

Feeding forage such as hay and haylage also helps keep horses hydrated.  It contains a large percentage of water that is released into the hindgut during digestion, forming a reservoir that is called upon when body fluid levels drop. Steaming hay is a great way to increase the water content, help improve hygienic quality and offset dehydration. Earing et al. (2013) found that steaming increased the water content of hay almost three fold!




If the weather suddenly takes a turn for the warm, then consider moving your ridden exercise to very early in the morning or later in the evening to avoid the hottest part of the day. If you need to partake in strenuous exercise in the sunshine, then try to allow the horse some time to acclimatise first. In hot weather ensure you include a proper cool down – at least 10-15 minutes of relaxed walking – into your training regime. Consider feeding electrolytes if your horse has sweated excessively during exercise to ensure they are able to recover properly and as mentioned above never, ever restrict water on hot days. 


Turnout vs stabling


It is quite common for people to restrict daytime turnout when the temperatures rise as they try to prevent their charge being bombarded by flies, overheating in the sun and eating grass right down. The knock-on effect is that horses are then left standing in their stables for long periods of time, where they may then be exposed to different health risks. Restricted movement in warm temperatures can mean legs begin to fill while dirty bedding getting warm and urine seeping into rubber matting both cause urea to be produced which results in ammonia gas irritating the airway.

Dusty bedding and forage can also cause airway irritation and should be considered. If you can ensure plenty of shade, a fly mask and fresh water (and in the case of pink-nosed horses, some sunscreen) leaving them outside might not be a bad idea. If you have to stable horses, consider using a Haygain hay steamer to ensure forage is free from dust and harmful microbes. The revolutionary Comfortstall flooring system is fully sealed and prevents urine seeping underneath it, stopping urea and ammonia production in its tracks. It also has an incredible ‘spring back’ which boosts limb circulation. 




If there is a prolonged dry spell then by mid-to-late summer grass growth will suffer and horse owners will find they may need to supplement grass with other forage sources. Hay is the most commonly fed dried forage in the world, but it can cause airway issues for horses. A recent study showed that 88% of the horses examined suffered from Inflammatory Airway Disease (IAD), and one of the main causes of IAD is respirable dust, a major source of which is hay. Using the Haygain hay steamer has been shown to reduce the risk of IAD by 65%, removing dust and killing other harmful microbes. 


Explore some of the Haygain products on their website to find out more about their wide-ranging benefits to horse health. Click here for the Haygain Steamer and here to read about the Comfortstall Flooring System.