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Electrolytes essential for performance horse diet

A well-balanced diet is essential every day to ensure working horses receive all required nutrients for fitness, recovery and overall health. Plenty of forage and a well-formulated performance horse feed are a great start.

Deciding which supplements to include can be challenging, given the large number of products on the market. Most of these supplements offer considerable benefits and play an important role in the diet, but the first that should be considered for a working horse’s diet are electrolytes.

Electrolytes are salts that play an important role in maintaining osmotic pressure, fluid balance and normal nerve and muscle activity. The most important electrolytes are sodium (Na+), potassium (K+), chloride (CI-), and magnesium (Mg++). These are lost daily in sweat and urine, and are lost in vast amounts when the weather is hot and the horse is working hard, trying to dissipate excess body heat through sweat. The major losses are of chloride followed by sodium and potassium, and therefore these are the most important electrolytes to replace.

All horses that work hard enough to break a good sweat will require electrolytes if they are to recover quickly and rehydrate. Travel and stress can also induce heavy sweating – a horse travelling a few hours to a competition on a hot day may lose up to 25 litres of sweat. If these losses are not replaced, the horse may start the competition already dehydrated.

Some horses sweat more than others, so it’s important to monitor sweat losses to determine how much needs to be replaced. It is easy to underestimate sweat loss on hot dry days because even though there may be considerable electrolyte loss, the sweat may quickly evaporate from the horse’s skin.

Substantial loss of electrolytes causes fatigue and muscle weakness, and can eventually decrease the thirst response. Research has also found that electrolyte deficiencies are a significant causative factor for muscle soreness and tying up in horses. The restoration of a correct dietary electrolyte balance can significantly improve this condition.

Since most of the electrolyte loss in the horse occurs through sweating, one method of calculating electrolyte requirements is to match the sweat loss. Body weight loss during exercise is a good way to estimate that, where 1kg of body weight loss equals 1 litre of body water and salt loss.

When choosing an electrolyte it is important to select a product that contains the correct proportions of the nutrients lost in sweat. Equin Electrolytes are available from Farmlands and have been formulated to mimic the composition of horse’s sweat, so all nutrients are replaced in the correct proportions.


For further assistance and advice on designing a diet for your performance horse, consult a reputable equine nutrition advisor.

Article supplied by Luisa Wood, Equine Nutrition Technical Advisor.