The Scoop on Equine Electrolytes

Most horse owners know how important it is for your horse to be hydrated, but it can be difficult to know if and when you should feed electrolytes. In this edition of “The Scoop On Supplements”, we will explain what electrolytes are and why they are important, ingredients found in electrolyte supplements and horses that can benefit from them, and even give you some tips for keeping your horse hydrated.

Electrolytes are essential minerals that support fluid regulation, nerve function, muscle contraction and relaxation, acid-base balance, and other important functions in the body. When there is an imbalance of electrolytes, issues such as dehydration, slow recovery, weakness, and muscle cramping are common. Even issues such as abnormal heart rhythm and metabolic problems are possible, which is why it’s important to make sure these minerals get replaced.

Electrolytes are lost on a daily basis through urine and feces, however, the greatest amount is lost through sweat. In fact, a horse exercising and sweating heavily can lose up to 15L of sweat per hour. While performance horses and those working in hot weather typically sweat the most, horses with lighter workloads and those living in milder climates also require these essential minerals.

The main three electrolytes that horses lose through sweat are sodium, chloride, and potassium. Calcium, magnesium, and other trace minerals are also lost but in significantly smaller amounts.

• Sodium: Sodium helps the body manage fluid balance by helping to retain water. Sodium also triggers the “thirst” sensation, which encourages your horse to drink. Sodium is lost at twice the rate of potassium. Horses at rest need about 1oz of salt daily.
• Chloride: Chloride pairs with sodium to create sodium chloride, otherwise known as table salt. Not only is chloride important for fluid regulation, but it is also used to support hydrochloric acid production in the stomach, and it helps maintain acid-base balance in the body.
• Potassium: Along with sodium, potassium helps regulate fluid balance, muscle contraction, and relaxation. Most horses get enough through their diet since forage is high in potassium.
• Calcium: The majority of calcium is found in the bones and teeth, however, it also plays a vital role in nerve function and muscle contraction.
• Magnesium: Magnesium functions as a cofactor for hundreds of reactions in the body, from energy production to DNA synthesis. It’s also critical for nerve function and muscle relaxation.
• Sugar: Although it’s not an electrolyte, sugar is added to supplements to increase palatability. While a small amount may be beneficial, too much can dilute the electrolytes in each serving so you will have to feed more to have the desired effect. If you’re looking to limit excess sugar, it’s a good idea to avoid products that list sugar, corn syrup, or dextrose as the first few ingredients.

Electrolyte supplements come in both powder and paste forms. Powders can be added on top of grain or diluted in a bucket of water. Paste is handy for use on-the-go, such as when trailering or during competitions.

For horses in light work living in mild climates, electrolyte requirements are usually met with a balanced diet. If you want to give your horse an opportunity to consume more salt without feeding a supplement, salt and mineral blocks are an easy addition to their stall or pasture.

Performance horses in heavy work, those that live in hot and/or humid climates, and horses under stress can benefit from 1-4oz of salt or an electrolyte supplement daily. If giving more than 2oz, try to split it up into two feedings during the day. As long as plenty of fresh water is provided and you are following the feeding guidelines listed on the supplement, your horse will flush out any excess electrolytes that they don’t need so you generally don’t need to worry about giving too much.