Adding supplements or electrolytes to water can decrease intake in horses.
A 1,000 pound horse should drink about 8 to 10 gallons of water each day. In order to encourage horses to drink, especially when away from home, owners frequently "flavor" (i.e. peppermint) their water; however sometimes electrolytes or supplements are added, which are different than flavors. The objective of this study, conducted by Land O'Lakes Purina, was to test the hypothesis that horses decrease water intake when supplements or electrolytes are added to water.
Six mature horses were offered both plain water and water with one of 4 different supplements. Additives included 2 electrolyte preparations (Farnam Apple Dex and Land O'Lakes Calf electrolyte), a vitamin/mineral (Farnam Red Cell) additive, and a joint additive (Finish Line Fluid Action). All additives were offered at a rate of 28 g per 5 gallons of water. Water intake from buckets was recorded via weight and replenished at 7:00 am and 6:00 pm each day. Horses were fed the same diets, had unlimited access salt, and were housed individually.
There was an effect of adding supplements and electrolytes to water as horses preferred plain water with a mean daily intake of 3 gallons versus 1 gallon for supplement or electrolyte water; horses drank over twice the amount of plain water compared to supplement or electrolyte water. There was no difference within the additive treatments for water intake. There was a trend for water intake to be affected by time of day, with the greatest volume consumed overnight. This trend may have been influenced by timing of water weighing and replenishment, and/or housing management conditions.
Adding supplements or electrolytes to water can decrease intake in horses. This may lead to dehydration, poor performance or other adverse health effects in horses. If planning to add supplements or electrolytes, acclimate the horse before traveling or placing the horse in a stressful condition.
Summarized by Krishona Martinson, PhD, University of Minnesota