Equine Care in the Summer Heat

Article by Kentucky Equine Research
This article is from the November 2023 Horse Deals magazine.

Ahh, the joys of summer. Hot days mean early morning rides, the smell of fresh horse sweat in your nose and the warm sun on your back (not to mention the steady hum of flies around your head!). Owning horses can be an absolute pleasure in the summertime, but just like the other seasons, summer feeding has its own problems to contend with.

Horses have a bit of a hard time in the Australian summer, especially in the hotter and more humid regions of the country where the weather puts special demands on your horse management skills!

Here is a guide to what is important, and how to deal with the hot weather and maintain a well-fed healthy horse.

Electrolytes

Hot weather means hot horses, and that means sweat, and if you like to ride your horse every day - lots of it! Horses sweat in a different way to us humans. When we sweat, we lose mainly water, with a small amount of salt, but when horses sweat, they lose a lot more salt and some protein too.

The ‘salt’ is really made up of a number of electrolytes. Electrolytes are salts that are vital in maintaining water balance and muscle function, amongst other important body processes. When a horse sweats a lot, and doesn’t get the lost electrolytes replaced, they may lose the stimulation to drink and will have tired and sore muscles.

The major electrolytes to be concerned about that horses lose in sweat are sodium (Na), potassium (K), chloride (Cl) and magnesium (Mg), with sodium and chloride being the major ones in horse sweat. For every day, it is important to make sure that your horse has 30 grams of plain salt in their diet (the same kind you put on your chips is fine! - you can buy it in bulk at your produce store). Either put it into their feed, or make a salt block available to them in the paddock, or do both, just to be sure.

Salt only replaces the sodium and chloride that the horse has lost, but if it hasn’t sweated much, the others are less important. On days where your horse sweats as you work them, it is a good idea to replace all of the electrolytes they have lost with an electrolyte supplement ideally formulated to be the same as horse sweat, so it replaces exactly what the horse has lost. If you live in one of the humid areas of Australia, then you will notice that your horse sweats more because the sweat doesn’t evaporate and cool them down very well. Electrolytes are very important for these horses and should be given every day after you’ve ridden, with a salt block always available in the pasture.

If you plan on doing lots of competitions this summer, you will need to take electrolytes with you, both for the competition and for the journey to get there. Lots of horses sweat during travelling, and need an electrolyte top-up when they get to the comp before they are worked. You can give the electrolyte in a syringe over the tongue mixed with water, yoghurt or apple sauce. Another alternative is to use a commercially available electrolyte paste.

Fibre

Horses have a need for at least 1.5% of their body weight as dry forage each day i.e. minimum of 7.5 kgs hay for a 500 kg horse. During summer months pasture quality lowers and pasture growth can slow, so don’t necessarily rely on grazing to meet your horses’ fibre needs. Most horses will need supplementary fibre including hay.

Grassy hay is often preferable to lucerne hay, but harder to obtain during a dry summer. In some areas, cereal hays such as oaten can be found, but remember that they typically have a high sugar content, so not suitable for all horses. Offering some lucerne hay is ideal for breeding and performance horses as it has a higher protein content.

With many parts of the country threatened by drought conditions, one of the biggest issues facing horse owners is the dramatic increase in the price of feed – particularly the price of roughage such as hay and chaff. Worse still is that the quality of hay available has dropped significantly, so incorporating some fibre alternatives in the diet may be needed. Alternative fibre sources include beet pulp and soy hulls. Fibre cubes are also a good roughage alternative, and in extreme situations straw can be fed if you can’t get hay. Prioritise quality if you can, because mouldy, dusty and weedy hay can cause health issues.

Feed Storage

Would you like to eat your dinner if it had been left outside in the heat all day? Your horse will give you the same answer. Hot weather makes feed go ‘off’ a lot sooner than it does in the winter, especially prepared feeds that have been soaked, so be sure not to store wet feeds for longer than a few hours.

When storing your feed remember pelleted feeds and straight grains usually store longer than muesli feeds. It is recommended to only buy enough feed to last you for 10-14 days. Keep your feed in a cool dry place, preferably in a shady feed room with plenty of ventilation. When you buy your feed, if the feed room is nice and cool, transfer it into sealable containers such as large rubbish bins with lids or purpose made feed bins to prevent flies and rodents getting into it. If the feed room is warm, as most are in summer, keep the feed in the bags to help air circulation and prevent ‘sweating’ (yes, your feed sweats too!) and consider using an air conditioner or dehumidifier in the feed room during the day. If you store your feed in bags, put them on a pallet rather than directly on the floor to allow air to circulate around them and prevent moisture from soaking into the bag. Make sure you remove shrink wrap or plastic bags from around the feed, as this will encourage them to sweat and go rancid more quickly, but roll the tops of the bags closed enough to keep flies out.

Keep your feed out of direct sunlight. If you feed oil, it’s a good idea to store it in a fridge; the same goes for molasses. If you feed straight grains, remember that cracked and rolled grains go off quickly in the heat, so inspect all your grains and feeds carefully every day for signs of mould, or musty smells - if they smell bad to you, you can be sure your horse will turn its nose up at them too.

Water

Probably the most important part of summer horse care is the provision of water. Your horse should always have access to fresh clean water, and on long rides stop for a rest and a drink at any rivers or streams that you pass. Feeding electrolytes to take care of sweat losses makes your horse thirsty, so be sure to give them a drink after they’ve had electrolytes. Horses can drink up to 50 litres of water a day in the summertime, so make sure they have a constant clean fresh supply. Algae in water troughs can build up quickly in the summertime, so check regularly, and thoroughly clean the trough often. If you use buckets for water, you will need to refill them regularly and clean them daily to avoid algae build up.

In summary, remember to prioritise hydration and quality fibre when feeding horses during the summer. We recommend consulting an equine nutritionist to ensure your horse’s diet is balanced based on the fibre sources you have available to you. But most importantly get out there and enjoy the summer days with your horses.

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