Electrolytes are used in horses to help control hydration levels. The main electrolyte that does this is sodium – the same sodium contained in sodium chloride, table salt.
Electrolyte needs vary from horse to horse and they will depend on diet. Generally speaking, as the weather gets warmer and the horse works harder, it will lose more electrolytes through sweating and will therefore need more in the diet.
Commercial horse feeds may not supply sufficient electrolytes, so you will need to supplement.
This can be done with an electrolyte supplement or even with ordinary table salt. Some horses will not drink water with electrolytes in, so instead add to feed.
For an average horse in hard work in the summer, a good starting point would be 50g per day, split between feeds, but do check with your vet first.
The electrolytes most commonly used in supplements – sodium chloride, calcium carbonate and potassium chloride – are not included in the FEI clean sport prohibited substances list.
Neither are other ingredients, such as sodium bicarbonate or glucose. Simple electrolyte supplements should, therefore, be safe for competition.
However, it is advisable to check the label of any supplement or ask the manufacturer. For the full list of banned substances visit www.feicleansport.org
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