Acidity of Water Affects Palatability for Horses

Horses are sometimes reluctant to drink water when they’re away from home. Owners suspect that the water may taste different enough to be uninviting, but it becomes a problem when horses refuse to drink, leading to possible dehydration and increasing the risk of colic and other health concerns.

How different does the strange taste, smell, or level of acidity have to be before horses will back off from a bucket of water? In a study conducted at the University of Guelph, twelve horses were offered control water with a pH of 7.5 as well as separate buckets of water that contained citric acid to change the pH to more acidic levels of 5.0, 3.6, or 2.9. Amount of water drunk from each bucket was monitored.

Consumption was highest from the control bucket. Less water was taken from the 5.0 bucket (moderately acidic). Horses did drink from the other two buckets (most acidic) at similar rates, but showed more aversion to these choices. This seems to indicate that horses avoid drinking strongly acidic water, though in this study it seems possible that either the smell or the taste produced the aversion.

To increase the chance that your horse will drink and remain hydrated when he is away from home, try one of these suggestions:

• Take his regular water along with you. This may not be practical on a trip longer than a day or two, because horses may drink 10 to 12 gallons (40 to 44 liters) or more per day.
• A few weeks before the trip, begin to add a small amount of flavoring (cherry drink mix, apple juice) to the horse’s water. Add the same flavoring to any water offered to the horse while he’s away from home. The flavoring may mask strange tastes or smells.
• Offer water in a familiar bucket. If the horse has a metal bucket at home and you take a plastic or rubber bucket on the road, it may be the look or smell of the strange container that makes the horse refuse to drink.
• Allow the horse to rest a bit after you reach your destination. After he has had half an hour or so to relax and nibble some hay or grass, offer the water again.