The Best Electrolytes For Your Horse
Martin W. Adams, PhD, PAS - Equine Nutritionist for Southern States
Electrolytes are minerals in the horse’s body fluids and tissues that are involved in muscle contraction, thirst regulation, nerve function and maintenance of blood pH. Commercial horse feeds, hay and pasture also contain electrolytes, but horses involved in performance, trail and show events, especially when travel is involved, need additional electrolytes to maintain good health and performance.
Horses use sweating as their major means of evaporative cooling due to the effects of hot weather and exercise. Electrolytes are needed to replace the minerals lost from sweat and to increase the thirst response due to water loss. There must be sufficient water and minerals in the horse’s body to allow sweating to occur at the proper rate and amount to keep the horse’s body temperature regulated. Heat stress from dehydration reduces muscular performance, and can result in heat stroke or exhaustion, which can be fatal. Also, sweat and urine losses can be great enough due to exercise, heat and stress to result in impaction colic.
Depletion of electrolytes in the horse interferes with muscle contraction and causes fatigue or poor performance, and severe loss of potassium results in symptoms similar to tying up disease. Electrolyte deficiency can produce nerve irritability that causes synchronous diaphragmatic flutter or “thumps”, a condition where the diaphragm contracts in rhythm with the beating of the heart. Lack of electrolytes and/or dehydration is also responsible for an exercise-related syndrome that causes reduced intestinal motility (a common reason why endurance horses are pulled from competitive rides at vet checks).
Horse sweat contains the electrolytes chloride, sodium, potassium, calcium, magnesium, and a few other trace minerals. The two electrolytes lost in the greatest amounts are sodium and chloride, which is salt, so a proper electrolyte should be salt-based to meet the horse’s needs. Five pounds of horse feed will contain about an ounce of salt and ten pounds of hay contains virtually no salt, but will supply the potassium needs for all but a hard-working horse in hot weather.
Most show, trail or performance horses receiving a normal daily diet of 15 to 20 pounds of hay and 5 to 10 pounds of fortified horse feed will only require one or two ounces of additional salt per day. This means providing 2 to 4 ounces of electrolytes daily, as the composition of a proper electrolyte for horses contains about 50% salt, so 4 ounces of an electrolyte will provide approximately 2 ounces of salt. EquiMin Horse Mineral, a granular vitamin/mineral supplement sold by Southern States, contains 25% salt. Two ounces of EquiMin Horse Mineral daily provides ½ ounce of salt, so additional electrolytes might be needed for a hard-working horse in hot and humid weather even if EquiMin Horse Mineral is provided.
When looking for an electrolyte for your horse, sodium chloride should be listed first on the ingredient list, followed by potassium chloride as the second ingredient. Electrolytes can be sugar-based instead of salt-based. Horses like the sugar-based electrolytes, but you won’t meet the salt requirements without feeding a lot of it.
Methods to administer electrolytes include adding water and oral dosing with a syringe, providing them in water for the horse to drink, and mixing them in a dry or wet form into the horse’s feed. Oral dosing with a syringe would be similar to dosing your horse with an oral deworming paste, and it can be difficult to be successful getting the electrolytes into the horse as some will try to avoid it or spit it out. When providing electrolytes in drinking water, always provide additional water without electrolytes, as one of the reasons you are providing electrolytes is to make the horse drink more water. A problem with providing water with electrolytes is that many horses are not used to the taste, and it takes time for them to get accustomed to it. Mixing electrolytes into the feed is the most popular way of getting the horse to consume them.
A good recipe for providing electrolytes to the horse is to add 1 to 2 ounces of salt or 2 to 4 ounces of electrolytes to one cup (8 ounces) of dry shredded beet pulp into a container or plastic bag. Then add at least 1½ cups (12 ounces) of water to the electrolyte-beet pulp mixture. Let the mixture soak for at least 30 minutes and add it to the horse’s grain meal or feed it separately through the day. If you need to provide electrolytes often throughout the day, such as an endurance event or trail ride, there is a risk of developing ulcerations in the horse’s mouth and oral cavity, so add a tablespoon of corn oil to the electrolyte-beet pulp mixture to help prevent them from occurring.
The other time to consider the use electrolytes is during cold weather, especially during the fall and winter seasons when horses are only fed hay and no pasture. When horses are kept outside continuously, or when water is not provided in insulated or heated containers during cold weather, horses tend to drink less. Horses prefer water that is 45-65o F and they will drink less if it is too hot or cold. The water content of pasture is about 80%, compared to the water content of hay, which is only about 10%. The danger that can occur with cold weather and hay-only diets is that horses can become dehydrated and the risk of impaction colic is increased. By force-feeding or top-dressing salt or electrolytes (2 ounces of salt or 4 ounces of electrolytes) on a daily basis whenever the temperature gets to freezing or below, the risk of impaction colic can be reduced.