How to Feed Electrolytes to Horses

We recently had a horse owner ask about providing electrolytes to her horses all at once, through the watering trough.  While in theory this might work, in practicality, it may cause some issues.

First, it is important to understand what horses need:

  • The key electrolytes are sodium, chloride, potassium and magnesium.
  • Forages and feed normally contain adequate potassium and magnesium to maintain body levels.

Then, we need to understand how a horse consumes & utilizes electrolytes:

  • The best way to add these to a horse’s diet is to provide free choice salt in a loose form at all times, as sodium and chloride are the primary electrolytes lost in sweat.
  • Horses may not consume enough salt if the salt is in block form, particularly during cold weather or hot, humid conditions.
  • Horses cannot store excess electrolytes and will excrete in the urine.

If you have particular events where the horses will be worked hard, particularly in hot, humid conditions, it is recommended to provide the additional electrolytes immediately prior to, during and immediately following a competition.  Maintaining water consumption is key to preventing dehydration and adding electrolytes to the water may not be desired.

Dr. Krishona Martinson at the University of Minnesota recently published a useful newsletter review that suggested that adding supplements to the drinking water for horses can actually decrease water consumption, which is exactly what you would want to avoid doing.

Warm Temps & Water Consumption

The transition in temperature and humidity from cool season to warm season may require an adjustment in watering horses. Reduced water consumption may impair performance and may increase the risk of impaction colic. Also, horses that are not conditioned properly may sweat more profusely than a well-conditioned horse, and thus dehydrate faster. This is particularly important early in the season when temperatures may change suddenly and horses may not yet be in peak condition.

The first key element is to make certain that horses have ready access to clean, palatable, cool water at all times or at very frequent intervals. Horses will normally consume about 1 gallon of water per 100 lbs body weight, so an 1100 lb horse will require a minimum of 11 gallons of water per day. This quantity can increase substantially during periods of exercise, high heat/humidity or for lactating mares.

Some tips to keep in mind to keep water consumption up:

  • Horses do not like to consume warm water in warm temperatures. Automatic waterers or large tanks, located in the shade and cleaned regularly, may be good options. If water is supplied in buckets, they need to be cleaned regularly and re-filled regularly.
  • If you are traveling to a show or other competition, it is essential to monitor water consumption, particularly if temperature conditions change.
  • It is routine in many barns to flavor the water with something like wintergreen or peppermint at home so that you can flavor the water in new facilities to match the home water.  Read here for tips on training your horse to drink water away from home.
  • Do NOT use soft drinks or any material containing caffeine as these can trigger positive drug tests.
  • Taking horses to facilities with chlorinated water can sometimes reduce water consumption without proper precautions.

The second key element is to make certain that salt is offered free choice. Things to keep in mind for salt consumption in horses include:

  • Horses require 1-2 ounces of salt per day, and this can increase to 6 ounces per day with exercise in hot weather conditions.
  • Loose salt is consumed more readily than salt blocks in many cases.
  • When evaluating the total diet for salt consumption, commercial feeds normally contain 0.5-1.0% salt. It is not typically any higher than this, due to problems with palatability.
  • If a horse has been salt deficient or is bored, they may over-consume salt while in a stall.
  • Additional electrolytes, commercial or personal recipe, may be used per directions before, during and following completion, but care must be taken to ensure that the horses are drinking adequate water. Administering electrolytes to a horse that is not drinking properly, or allowing a horse to over consume salt without adequate water, can lead to electrolyte imbalances. If electrolytes are added to the water, plain water should be offered also.

Horses need to be offered water throughout the day at a competition, and should be re-hydrated following exertion. They cannot cool out and recover properly without being re-hydrated. Keeping horses properly hydrated and maintaining electrolyte balance is extremely important in order to make a safe transition from cool temperatures to summer time and competition.

Leading a Horse to Water…

Water is the most essential and important nutrient for you and your horse and should be available to your horse at all times. Good hydration is vital to optimal health and performance. With all of the bad things that can happen if a horse doesn’t drink properly, it’s no wonder horse owners, myself included, get anxious about making sure their horse is consuming adequate amounts of H2O, particularly when we are away from home.

So what is a horse owner to do in these cases? The old adage which says ‘you can lead a horse to water, but you can’t make them drink’ may be true. However, with a little preparation before heading out to hit the trails or this year’s show circuit, most horses can be trained to drink. Providing free choice access to salt, bringing along water from home, using electrolytes, and doing things like soaking feed can all help, and training your horse to drink is one more tool you can add to your box of tricks. Supplies are cheap and easy to obtain. I like to use the smaller 8qt buckets – they are easier to hold, especially if watering in a trailer.

  • To begin, I wanted my gelding to associate the small “water” bucket with a yummy treat. So I started giving him his favorite treat – chopped up carrots, a little unsweetened applesauce, and a small handful beet pulp – in the bucket without water. He quickly learned that that bucket meant something yummy.
  • Once that positive association was made, I started adding just a little water over the treat, just enough to cover the carrot chunks (1 – 2 inches) and get the applesauce in solution so the water was “flavored”. The idea is to get his nose wet to get the treat, and he would be rewarded for slurping everything up through lots of verbal praise and the food treat. There are many things you can flavor water with, its just a matter of finding what your horse finds irresistible:
    • Gatorade, applesauce, commercial water flavors, carrot shreds, small handful of grain concentrate, small dollop of molasses, peppermints, etc.
  • Once he accepted the water addition to his treat, I started giving his “water treat” in different locations around the farm (in the cross-ties, by the horse trailer, in the horse trailer, outside of the arena, in the pasture, etc.) AND as soon as we were done working, just as his caveson or bridle came off after being properly cooled out. After a few days of doing this, he started expecting his “water treat” after work.
  • Now that we had established this behavior, it was time to add more water, filling to ¼ of the bucket and letting him get used to that, then filling to ½ bucket, letting him get used to that, and so on, until he was drinking most of a small bucket when I put it in front of him.
  • After a little time I started backing off of the flavor so the mixture got more diluted, but making sure he still got a treat reward for finishing off the bucket each time. That way if he ever got really stubborn about drinking or if I were masking water that was noticeably different from water at home, I could add more flavor back to entice him to drink.
    • Also, since adding things to water can be a labor intensive (buckets need to be cleaned more frequently), the less you have to add, the more practical it is.
    • Another trick, especially when you get to the full bucket stage, is to let the horse watch you add the treat (carrot/apple chunks) to the water, so they stay engaged and interested. If they back off drinking, then go back to the previous step or the step before that and re-establish the behavior, then move on again.

The idea of adding flavor initially is to develop the consumption behavior through positive association, and then wean them off of it gradually while the behavior is retained. If you regularly offer your horse flavored water, be sure they have access to clean, fresh, un-flavored water as well. Also, take care not to go overboard with sugary flavors in your water to avoid digestive upset. It would be counter-productive for your horse to associate a “tummy-ache” with drinking.

Lastly, don’t forget to keep yourself well hydrated along with your horse. Cheers!