Winter Water Concerns for Horses

Maybe you’ve noticed - it’s been cold outside lately. If you own horses, you may be concerned about the amount of water your horses are consuming. Because of the increase in dry forage a horse consumes in the winter and a lack of foraging activity, too little water in the equine diet may lead to impaction colic.

During the summer months, pastured horses spend the day foraging, walking from one patch of grass to the next collecting succulent, moisture and nutrient rich feed. When cold snowy weather arrives, horse owners are forced to switch their steed’s diet to preserved feed, most commonly in the form of dry hay.

Dry hay is just what it sounds like, dry. As the weather gets colder horses require more hay to provide the energy needed to keep warm. For each decrease in temperature of one degree Fahrenheit below the “critical temperature”; (which for a horse in good flesh with a dry, heavy coat is 30 degrees) there is an increase in digestible energy required to maintain body temperature. For example, the temperature including wind chill is 20 degrees F, your horses’ energy requirement increases by 2 Mega calories (Mcals) per day, this translates to an additional 2 pounds of average quality hay per day. The average 1000 pound horse should already be consuming 15 pounds of hay and now will need 17 pounds of hay to avoid a loss of body condition.

Recent temperatures in the -10F range would require such a large increase in hay consumption that most horses could not consume enough hay to avoid weight loss. Adding concentrates (grain) to the diet will help to meet your horses energy needs, be sure to add grain slowly (over a period of weeks) to avoid digestive upsets that can lead to colic and founder.

Horses tend to reduce their water intake as temperatures fall. This reduced water intake in addition to an increase in dry hay consumption can lead to a greater incidence of

impaction and colic. Horses require between 8 and 10 gallons of water per day, cold water and ice will reduce the amount of water most horses will drink. Horses will eat snow to obtain needed moisture, but putting cold snow into a cold horse will only increase the energy needed to maintain body temperature.

Water consumption is most easily measured when horses are watered in buckets in their stall. If buckets are used, offer enough water so that the horse has access to more than the minimal 8 to 10 gallons per day, add buckets if necessary. Try to maintain water intake above the minimal amount, a study of water consumption during cold weather has indicated warming the water to well above freezing, around 90 degrees, increased water consumption roughly 40 percent. An easy way to accomplish this is to bring a half bucket of hot water from the house and mix it to the desired temperature. It is probably not necessary to warm the water for all of your equine charges, only those who are not drinking enough, elderly horses and those with a history of impaction.

The addition of salt to the diet will also increase water consumption. Most horses will do well with free choice salt in either block or loose form. It is dangerous to force a horse to consume salt unless there is free access to clean water.

Remember, winter or summer, the rule is the same: if you wouldn’t drink the water, don’t ask your horse to drink it.

Tina Savage, UNH Cooperative Extension Educator, Agricultural Resources, Carroll County