We tend to work our horses harder in the warmer months. The harder the horse’s body works, the more energy it burns, and the byproduct of this energy process is heat. As a result, keeping horses cool and hydrated in hot and/or humid weather becomes a primary focus of horse owners in the summertime.
The body’s cooling efficiency is determined by environmental temperature and humidity, as well as the physical and metabolic condition of each individual horse. While thoroughbreds and Arabians have an easier time staying cool, heavily muscled horses like quarter horses and warmbloods can face bigger challenges when dissipating internal body heat.
The more fit the horse is, the more efficient the horse becomes at dissipating heat; horses that are overweight can be hampered in the recovery phase by the fat layer that traps heat. Yet even fit horses, when working in conditions of high heat and humidity, will lose varying percentages of water and electrolytes, and can be slow to replace muscle glycogen.
Cooling down: Walking, scraping and rinsing
During warm months, the cool-down phase of walking after a training session helps to redistribute the blood in the body. In the cool-down phase more blood is circulated to the skin, lungs and organs, and less to the muscles. This helps pull heat out of the horse’s muscles and dissipate it through the skin and through the lungs. Walking helps restore the horse’s heart rate and other vital signs to a normal range.
One of the most important parts of cooling the horse’s body with water is the sweat scraping. Water left on the coat, particularly in humid conditions, acts as an insulator. Don’t forget to towel-dry the legs as well.
Additionally, there are many water-based rinses that you can sponge on your horse to ease sore muscles and aid in the cooling process. One of the easiest ingredients to add to water is apple cider vinegar, which provides cooling properties for the skin.
Water for hydration
It’s good practice to check the hydration of your horse with the simple skin pinch test. Pinch a small piece of the skin in the neck or shoulder area. If it stays elevated or “tented” for as little as three seconds, your horse is moderately dehydrated. At four seconds or more, your horse is severely dehydrated.
Capillary refill time is another good test for hydration. Press a finger to the upper gum for one or two seconds. When you remove your finger the normal, pink color of the gum should return in one to two seconds. If it takes longer for the color to return, your horse is probably dehydrated.
When horses sweat to cool themselves, they not only lose fluid, but also massive amounts of electrolytes. Muscle recovery and the synthesis of glycogen after exercise is dependent on intercellular water and electrolytes. Horses can’t replenish muscle glycogen as quickly as humans do.
Electrolytes combined with water provides fast delivery through the oral transmucosal pathway. Oral transmucosal absorption is rapid because of the rich vascular supply to the oral mucosa. Even the respiratory tract provides a large mucosal surface for water, nutrients, and electrolyte absorption.
A study conducted at Michigan State University by Hal Schott, DVM, showed that adding electrolytes, particularly salt added to water, helps to maintain the horse’s thirst drive.
“An initial drink of salt water improved recovery of sweat fluid losses because horses drank more water when it was offered a few minutes later. With that initial drink of salt water, the salt concentration in the blood remains elevated to activate the drinking centers of the brain. In contrast, horses that were offered plain water for their initial drink did not drink further during the initial hour of recovery, despite the fact that they remained partially dehydrated.”
Electrolytes added to feed is a much slower delivery system than electrolytes in paste or added to a bucket of water. Don’t depend on a salt lick or salt block for all the electrolyte needs of your horse in hot weather. If your horse is dehydrated, it is especially important not to add electrolytes to the feed. Electrolytes given without water can cause further dehydration.
After your horse is cool, provide electrolytes either by paste syringe or in water. Prepare two buckets of water: one with the electrolytes, one with plain water.
Keep in mind that some horses can develop ulcers to the mouth and stomach from the overuse of electrolytes. Some horses are sensitive to paste-based electrolytes given on an empty stomach unless gastric protection is added to (or included with) the electrolyte formula.
The role of amino acids in the recovery phase
Research has shown that the branched-chain amino acids (BCAAs) and the essential amino acids fed after exercise can support muscle repair and growth.
Alfalfa pellets or cubes are a wonderful post-exercise recovery food because they provide the essential amino acids and BCAAs. (Adding a banana to the alfalfa pellets or cubes helps replenish glycogen and makes a good post-exercise snack.)
Antioxidants play multiple important roles:
- Limiting oxidative stress, and assisting in quicker recovery time after exercise, competition, or in countering the effects of environmental stressors
- Reducing muscle damage from training, thereby reducing stiffness and soreness
- Providing for senior horses’ and metabolic horses’ greater requirements for protection against free radical damage
Key antioxidants include: vitamin E, vitamin C, beta-carotene, the carotenoids, CoQ10, SOD, selenium, the flavonoids and flavonols, quercitin, and glutathione.
Supplements for recovery
Rebound EQ provides a blend of foods high in BCAAs and essential amino acids, plus bovine colostrum for immune support and for cellular repair of muscles and tissues. Rebound also provides a range of active, viable probiotic strains for the GI tract, along with the sea vegetable alaria (rich in macro- and micro-minerals, vitamins, fiber, and protein), plus smectite clay that can bind toxins at a greater rate than other clays. This formula is especially recommended for horses on layup from injury, horses coming back into work, or horses in the process of getting fitter. Can be used as needed.
Starlyte EQ provides a blend of mineral-dense salts from land and sea for electrolyte and trace mineral needs. Also provides the sea vegetable alaria for additional macro- and micro-minerals, vitamins, fiber, and protein. Contains organic mango powder for a healthy sodium/chloride balance in the body, and smectite clay to soak up exercise-induced toxins and free radicals. This formula is added to feed, not to water. Recommended for horses in light to moderate work.
Aqua-Forte is a water enhancer that provides good hydration and essential support for electrolyte replacement. The formula includes electrolytes from Celtic sea salt in the same ratio as sweat; mineral and vitamin support from the sea vegetable alaria; cellular energy and CoQ10 support from the bio-resin shilajit; GI tract support from organic fennel seeds; and provides organic apple powder for antioxidant support. This formula is added to water for faster electrolyte replacement and hydration needs of the horse. Can be given to horses of all ages and levels of activity. Aqua-Forte is especially beneficial during periods of extreme heat and/or humidity. Can be given as needed.
Alixir is a comprehensive water enhancer for high-performance horses, formulated to address electrolyte needs, cellular energy support, antioxidant support, protection of the GI tract, and reduction of cortisol from stress. Alixir provides electrolytes from Celtic sea salt in the same ratio as sweat; mineral and vitamin support from the sea vegetable alaria; and shilajit for mitochondrial support and energy production including ATP and CoQ10. Also includes: organic holy basil for adrenal and glandular support, helping to normalize cortisol levels in the body; medical-grade microcrystalized aloe to coat the GI tract and protect intestinal mucosa; camu camu and organic apple powder for antioxidant support through several components including beta carotene, the carotenoids lutein and zeaxanthin, vitamin C, bioflavonoids, and quercitin. Alixir powder is added to water for fast electrolyte replacement, hydration and recovery. The paste version of Alixir will be available in July, 2018 and includes camelina oil for added vitamin E, and organic barley juice powder for the super-antioxidant SOD.
The new normal
According to data based on research by James Hansen, a retired NASA climate scientist and professor at Columbia University, summer temperatures have shifted towards more extreme heat over the past few decades.
His research showed that from 1951–1980, temperatures across a third of the Northern Hemisphere were near average or normal range, a third were considered cold, and a third were considered hot. Since then, summer temperatures have shifted drastically; from 2005–2015, two-thirds of the values were in the hot category, and nearly 15% were in a new category: “extremely hot”.
What this means for our horses, is that we have to be even more mindful and diligent about cool-down after exercise, electrolyte replacement, hydration, and recovery.