Why You Should Feed Electrolytes to Your Horse

5 min read

Electrolytes are essential minerals to help your horse’s body function normally. In this blog we discuss the impact electrolytes have on horses and why it’s so important to replace them.

What are electrolytes?

Electrolytes are minerals that dissolve in the body’s fluid to create electrically charged ions. They’re important for a variety of processes in the body to keep it functioning normally. The most important electrolytes that horses require are Sodium (Na⁺), Chloride (Cl⁻), Potassium (K⁺) and to a lesser extent Magnesium (Mg²⁺) and Calcium (Ca²⁺). Sodium and chloride are the main electrolytes that are present around the cells and in blood, while potassium is the primary electrolyte present within cells. Magnesium and calcium are important electrolytes for muscle contraction and relaxation.


Why do horses need electrolytes?

A horse’s body contains approximately 70% water. This water is spread across the body into two main areas: inside of cells (intracellular) and around the cells (extracellular), including in blood. It’s important that the fluid between these areas remains balanced and is kept from varying too much. Electrolytes are essential to ensure this balance is maintained so that the body can continue to function normally. Sodium and potassium are the most important electrolytes in maintaining fluid balance and normal circulatory function. As electrolytes carry an electrical charge, they’re also essential for establishing proper electrical gradients across cell membranes. This allows cells to send and receive electrical signals which is critical for normal nerve, muscle, and brain function. Electrolytes also help to control the body’s pH (acid/base balance), help with the transport of nutrients into and out of cells, are involved in metabolic processes and also assist with the elimination of waste products from cells.


How are electrolytes lost and what happens if they aren’t replaced?

Electrolytes are normally lost daily from the body in sweat, tears, digestive secretions, urine, and faeces. A substantial amount of electrolytes can be lost through sweat as horses can produce up to 10 – 15 litres per hour when exercising, especially in hot, humid weather. The five main electrolytes are lost through sweat in varying amounts. Chloride and sodium make up the largest proportion of the electrolytes lost through sweat, followed by potassium and then in very small amounts calcium and magnesium. Illness, medication, weather, and fluid intake can also affect the loss of electrolytes from the body.

Horses do not produce their own electrolytes; they must be consumed as part of the diet. If lost electrolytes are not replaced, it can have some detrimental effects on how the horse’s body functions. Horses that have low levels of electrolytes can experience fatigue, muscle weakness, lethargy and can reduce their food and water intake. Recovery times can become longer, and performance reduced. Horses that become deficient in electrolytes may have a reduced sweating capacity which can result in the animal overheating when exercising, they may also become dehydrated, lose weight, and can also be predisposed to “tying-up”. In extreme cases, deficiencies can result in colic, collapse and even death. 


When do horses need electrolyte supplements?

Horses vary in their daily electrolyte requirements. The amount and type of electrolytes required by a horse varies based on the amount and type of work they are doing, their fitness, the environmental conditions they are performing in and normally live in, diet and their tendency to sweat. Even when not in work, horses will generally have higher requirements for electrolytes in hot and humid conditions, particularly those that are kept in paddocks without shade. Generally, if the temperature is greater than 30°C, horses will sweat more and require more than their recommended daily nutritional requirements for sodium, chloride, and potassium.  

Most horses won’t need an electrolyte supplement on a day-to-day basis. Leisure horses or those in light work that are fed a high forage diet will generally get enough electrolytes if plain table salt (NaCl) is added to their feed. Alternatively, providing free access to a salt lick or block can also provide sufficient electrolytes for maintenance. Electrolyte supplementation may be needed for horses during long periods of hot dry weather or temperatures over 30°C with high humidity. 

Horses undergoing harder work or that are competing in hot and humid environments are more likely to lose greater amounts of electrolytes through sweat. These horses will have a larger electrolyte deficit and are likely to benefit from a supplement. Replacing electrolytes helps keep these horses hydrated and aids in the recovery process after training and competition. In situations where exercise is prolonged, such as endurance riding or long hot days moving stock, horses can also benefit from a supplement being provided during the exercise. These supplements should be specifically formulated for use during exercise and should not be given unless there is free access to clean water available.

Electrolyte supplements can also be beneficial in stressful situations such as when travelling or settling into a new environment (such as for a competition/race or a new home). During these times horses may not be eating as much feed or hay as they usually would. Supplementing can replace electrolytes that are not being consumed in the diet until your horse is relaxed and eating normally again. As some horses don’t like the taste of water if it’s different to what they drink at home, adding the supplement to the water at home before you travel can help to disguise any change in the taste of water.


How to supplement electrolytes

There are many electrolyte supplements available on the market that come in a variety of flavours in pastes, powders, or liquids. A good supplement should contain the five main electrolytes with sodium, chloride, and potassium as the main ingredients. Many supplements will contain glucose as a main ingredient to make it taste better but the aim of electrolyte supplementation is to replace salts, not sugar. So, it’s best to avoid supplements containing glucose as a main ingredient.

Depending on the type of work a horse performs and the product being used, electrolytes may need to be supplemented before, during or after exercise, competition, or travel. Regardless of the nature of work, horses should be fully hydrated before performing. Always ensure horses have free access to clean drinking water when giving electrolyte supplements and follow the directions on the label to avoid overdosing or dosing at an inappropriate time. 

If a horse has lost a large amount of sweat, they may need to drink at least 20 litres or more of an isotonic solution (a liquid that contains the same amount of electrolytes in water as sweat) to replace the electrolytes that have been lost. An easier solution is to feed an electrolyte paste or powder such as Horseland Electrolyte Powder and ensure adequate water is provided. When large amounts of sweat have been lost or horses have performed harder and longer than usual, it can be beneficial to continue supplementing electrolytes for 2-3 days after performing to assist with recovery and restoring electrolyte balance.

Getting horses used to the taste and flavour of electrolyte supplements is recommended so that they don’t refuse food or water containing them when they are needed. Mixing a small amount in feed or water and gradually building up to the required amount over several days or weeks is an easier way to get horses used to eating or drinking them rather than only giving them when required. Additionally, it’s better to build electrolyte intake up rather than excessively loading a horse with one dose of electrolytes on the day of competition or a big race.


Important things to remember about supplementing electrolytes

  • Always make sure your horse has access to clean, fresh water when giving electrolytes as a supplement, including plain table salt. Horses can quickly become dehydrated with supplementation if they don’t drink an adequate amount of water as well.
  • Never give electrolytes to an already dehydrated horse, especially if it’s not drinking. Call your vet if you think your horse is dehydrated.
  • Try and get horses used to the taste of a supplement before a competition or race. Don’t assume they will like the taste as this may result in horses refusing to eat or drink.
  • Always have free access to a salt lick or block, especially in hot, humid weather.
  • Avoid adding electrolyte supplements to an already fussy eater’s feed. Try mixing with molasses or applesauce to disguise the taste.

Always follow the directions on the label to avoid overdosing or giving the supplement at the wrong time. Ensure you know the correct way to use the supplement not all powders can be mixed in water and not all liquids or pastes can be mixed with feed.


Ensure your horse is the best version of themselves with our new Horseland Health products! To shop the new range and give your horse the nutrition they deserve head into your local Horseland store or browse online.