Oral electrolyte supplementation and prevention of dehydration in horses

Abstract

Dehydration is common in equine disciplines and can be avoided by effective oral rehydration strategies. Thermoregulatory loss of heat in horses requires sweating which, in turn, can result in considerable loss of water and electrolytes. Maintenance of hydration and prevention of dehydration requires the continuous replacement of lost electrolytes and water. The stomach and small intestine can function as reservoirs to facilitate the uptake of water and electrolytes consumed 1–2 hours prior to competitions, training and transport. Ions and water are rapidly absorbed in the small intestine and taken up by muscles and the skin, where they serve to replace losses resulting from muscle contraction and sweating. An effective electrolyte supplement replaces electrolytes in the proportion that they are lost through sweating; failure to do this results in an electrolyte imbalance. Electrolyte solution osmolality must be maintained at less than that of bodily fluids to promote gastric emptying and intestinal absorption. Palatability of the electrolyte supplement should be high, and horses should be trained to drink the solution voluntarily before any dehydrating event to try to prevent dehydration from occurring.