Horse Water Requirements: Five Important FactsBy Kentucky Equine Research Staff · November 1, 2016
There are six nutrients in a horse’s diet: carbohydrates, protein, fat, vitamins, minerals, and water. Each of those is considered essential, yet water is king of the hill.
“A horse can live for almost a month without food, but within a mere 48 hours without water a horse can begin to show signs of colic and can quickly develop an impaction, lethargy, and life-threatening sequelae. A horse can only survive about five days without water,” shares Peter Huntington, B.V.Sc., M.A.C.V.Sc., director of nutrition at Kentucky Equine Research (Australia).
Consider these five points to ensure the proper quantity and quality of water is being offered to your horses year-round:
1. Horses normally consume between 5 and 15 gallons (approximately 20–55 liters) of water in a 24-hour period. The individually stabled horse is usually easy to monitor for water intake if you are filling five-gallon buckets two or three times a day. If a horse is kept on pasture or in a herd on pasture, assessing water intake becomes increasingly challenging, but not impossible.
“Hydration can easily be assessed in individuals within a herd by feeling their gums to ensure they are moist and pinching a small area of skin on their neck or shoulder to watch it bounce back to its normal position,” advises Huntington.
2. Field-kept horses obtain moisture from pasture. In fact, fresh pasture is approximately 60–80% moisture, meaning they obtain a substantial amount of water while grazing. In contrast, grains, concentrates, and baled hay contain far less moisture, which means horses need to drink more to meet their water needs. Another factor to consider in a herd situation is pecking order. If you suspect that one or more horses are being chased away from the water trough, consider adding a second trough.
3. Weather and exercise can impact water consumption. Typically, horses consume more water during the hot, humid summer months. That said, some horses actually drink more water in the winter than in the hot summer (recall that the quality of forages is generally not as good as in the summer, with less moisture). It’s also important to bear in mind that horses are different and do not need to consume the same amount of water to remain healthy.
4. Underlying health issues can impact water consumption. Diarrhea or chronic kidney disease in particular can cause increased water losses from the body that need to be replaced. Such horses will need extra water to facilitate recovery and maximize quality of life.
5. “Natural” sources of water such as streams or ponds should not be used as the horse’s primary water supply. If they choose to drink from those sources, it is not usually a concern, but they should still be offered fresh water. The quality of streams and ponds cannot be guaranteed, and pollution or algae blooms can impact the safety of those water sources at various times throughout the year. Horses can also have difficulty accessing the water in ponds and streams if the shores are muddy or frozen.
Learn about water requirements for horses and more by reading KER's technical guide Horse Care and Management.