We have rather inconsistent summers here in the UK, and hot weather can come out of nowhere. When the temperature rises many owners will be wondering if their horse needs to be given electrolytes.
Electrolytes are minerals which are required by the horse to maintain homeostasis, basically keeping everything normal. These minerals help your horse balance fluid levels in within cells, are required for muscle function, and assist the transmission of nerve impulses.
Electrolytes also help transport nutrients and waste products in and out of cells, so it is fair to say that they have some essential roles to play within the horses body.
Sodium, Chloride, Potassium, Magnesium and Calcium are the main electrolytes required by the horse, and these are lost through sweating, urine and faeces.
Signs that your horse may be lacking electrolytes are:
Electrolyte loss can be substantial when your horse is working hard, due to the amount of sweat produced by your horse. The horse has very large muscles which produce a lot of heat, and the horse’s main mechanism of cooling itself down is by sweating. Your horse can produce 10-15 litres sweat per hour,
The horse cannot retain water without the presence of electrolytes, so just giving water will not rehydrate your horse.
Ironically when your horse (or indeed the rider) becomes dehydrated his thirst response is switched off, so the horse may not want to drink. Sodium is often considered the most important electrolyte as it regulates thirst.
Your horse will receive some electrolytes from its hard feed and forage, but to help you decide if you need to give an additional supplement consider the following
A horse working hard in hot weather would certainly benefit from electrolytes, particularly if they are sweating when travelling to competitions. However this does not need to be a high level or race horse. A leisure horse competing or working hard training at home in hot weather would probably sweat sufficiently to require electrolytes. Feeding an isotonic solution, simply a solution where electrolyte levels are the same concentration as body fluids, will help re-hydrate your horse replacing both fluid and electrolytes.
One method of giving electrolytes is via a water buffet. Offer your horse a bucket of clean fresh water and one containing electrolytes. You can either buy a pre-prepared solution or you can use a 2:1 ratio of standard salt lo-salt.
It is worth getting your horse used to drinking this in training so that when he really needs them he is used to the taste.
You can give an electrolyte supplement in feed as well, this will stimulate thirst so make sure clean fresh water is available at all times.
For those in lighter work access to a salt lick or adding 25mg of salt to feed per day would meet their requirements for sodium, and would keep them drinking. A salt lick alone is not sufficient for horses working hard because this is only replacing sodium and it is dependent on their willingness to consume from the salt lick. Several studies have found that willingness of horses to consume sodium, consumption varies from 0-31 g Na/day to 0-79 g NaCl/day. So horses’s don’t always know what is best for them!
Worried about your horse not drinking enough? You might find this article useful https://www.nkcequestrian.com/9-ways-to-keep-your-horse-drinking/