Electrolytes and Muscle Function in Horses: Essentially Linked

Electrolytes play a vital role in maintaining hydration, muscle contraction, nerve function, and fluid balance in horses. Sodium, chloride, potassium, calcium, and magnesium are lost through sweat, urine, and feces, with heavy exercise and hot, humid conditions increasing these losses. Because horse sweat is highly concentrated with electrolytes, deficiencies can lead to fatigue, dehydration, muscle cramps, and conditions such as “thumps,” which occurs in severely dehydrated horses.

Horses receiving furosemide may experience even greater electrolyte losses, making careful replenishment especially important. Research shows that balanced electrolyte supplements are rapidly absorbed, helping horses maintain hydration, improve exercise performance, and recover more effectively. However, excessive supplementation can disrupt acid-base balance and irritate the stomach, so electrolytes should be fed according to recommended guidelines and preferably with feed or diluted in water. Studies also found that adding dextrose does not improve electrolyte absorption. Proper hydration, balanced nutrition, and appropriate electrolyte supplementation are essential for optimal performance and recovery.