An Ounce of Prevention….or Table Salt!
By, Steffany Dragon
Maintaining a thriving horse is very often in the details. You’ve heard the saying that an apple a day keeps the doctor away…well, topdressing a tablespoon of plain, non-iodized table salt to each feeding per day might be the most critical, easiest, and cheapest supplement you add to your horse’s feeding routine. Especially in cold weather when horses are apt to drink less, you can count on salt to keep them drinking.
Q. In the horse, can you guess what nutrient is essential for…(Briggs, 2007):
-maintaining gut health and critical for digestion
-thermoregulation (maintaining your horse’s body temperature)
-eliminating toxins through urine and sweat
-cushioning the central nervous system
-health healthy eyesight and hearing
A. Water! Other facts about water that emphasize its importance to your horse: percent body composition of water (70% of his weight is water), how few days a horse can survive without it (3-6 days), the fact that every single cell in the horse’s body needs it, a horse at rest requires at least 12 gallons of water a day (Table 3, below)!
The saying goes, “You can lead a horse to water, but you can’t make him drink,” but in reality, when you bring a horse to water, you don’t have to make him drink, you just have to make him thirsty! In cold temperatures, the main purpose of adding salt to your horse’s diet is to keep him drinking and hydrated even when his body might be telling him he is not thirsty. That’s right…Horses do not always know they are thirsty. Here’s why: Through physiological triggers sensitive to the imbalance of water and sodium in a horse’s body at any given time, the horse’s body initiates survival mechanisms through hormones that place the highest importance of maintaining the correct water to particles ratio in the blood. While this is important for survival, retaining water from other critical pathways (kidney detoxing through urination, for example) to do this would be detrimental if it persists and the horse stays in a dehydrated state. To complicate matters, if your horse is not getting enough sodium (salt), yet another hormone tells the body not to let sodium leave but triggers the release of potassium in the blood instead causing an electrolyte imbalance (all in an effort to maintain the correct osmolarity in the cells), which can result in muscles being overly excitable, causing tying up, weakness, or fatigue, excessive sweating than anhidrosis and a rapid heart rate. The take home message? Provide adequate sodium so your horse will drink enough water daily.
How Much and What Type of Salt?
Among other important benefits, staying hydrated supports gut motility and prevents colic, the number one killer of horses. Providing a plain, white salt block within easy reach of your horse is the very least you can do but is only effective IF you know he is consuming at least 2 tablespoons (about 1 ounce) a day, his maintenance requirement of salt a day when not in work. A 5 lb salt block should be consumed within 2 months if he is indeed ingesting enough. While in work, 4 tablespoons a day would be required so that would be, let’s say, 2 tablespoons sprinkled on feed twice a day (Getty, 2016). A brown/mineralized block is not necessary when feeding a commercial feed or diet balancer, as the minerals are already in the formula at the appropriate ratios. The take home message is that to keep your horse drinking, it is as easy as adding plain table salt to whatever he likes to eat. While salt replenishment on a hot humid day can require as much as an ounce of salt per hour, it is also important to replenish the other salts besides just NaCl (table salt) that are lost in the composition of sweat. That is where electrolytes come in. However, in cold temperatures, the main purpose of adding salt to your horse’s diet is to keep him drinking and hydrated even when his body might be telling him he is not thirsty.
Human vs Horse: Excess salt in humans can cause high blood pressure, which can result in heart disease or stroke. Rest assured that Humans and horses have different types of hearts: horses do not suffer from the same heart diseases that humans do. National Research Council advises that as long as adequate water is available excess sodium will be excreted in urine and gives the maximum tolerable concentration in the ration of 6 percent of total feed intake.
While table salt will keep your horse drinking and hydrated, it will not replace what is lost from perspiration during hot and humid temperatures or from exertion by the performance horse. Electrolytes should only be given to a horse that is already in a good sodium balance and drinking appropriately. Providing your horse
with adequate salt each day can go a long way in maintaining hydration which not only safeguards health but supports optimal performance as well. A good performance electrolyte, like Aqua-Aide® https://equineoutfitters.biz/product/aqua-aid-equine-elecrolyte/is indicated for horses who need to replenish vital water and body salts lost from significant sweating. Performance and recovery can be significantly improved in these situations by using these as directed. NOTE! These electrolytes are recommended for healthy athletes. When performance horses are in moderate to intense work, their system becomes alkalotic VS When a horse is sick with diarrhea, their system becomes acidotic. Therefore, do not administer a performance electrolyte to a sick horse, as their body is in a very different state. A word to the wise also. Research found that concentrated electrolytes like pastes may lay in the stomach and small intestine and draw water from the body when they are absorbed. This process may dehydrate a horse in the short term when rehydration is most critical. Discuss using any electrolytes in a sick horse with your veterinarian.
Briggs, K. (2007). Understanding Equine Nutrition. Lexington, KY: Eclipse Press.
Getty, J. M. (2016). Feed Your Horse Like A Horse. Getty Equine Nutrition, LLC.