During hot, humid weather, your horse may not drink enough water to keep up with fluid loss. When that happens, dehydration can occur.
Horse dehydration is more common in the summer, but it can happen at other times of the year, too. Intense activity in hot, humid weather is the most common cause, but an active horse in a hot, poorly ventilated stall or without access to sufficient water (think frozen water buckets!) Can become dehydrated, too.
There are some simple things you can do to get your horse to drink more water.
1. Make sure he has enough water. An idle horse needs a minimum of ten gallons of water a day and an active horse in hot weather can suck up 25 gallons.
2. Make sure the water is clean, clean, clean and easy to access. Tipped over, leaky or funky water buckets will not encourage your horse to drink any more than they'd entice you.
3. Soak hay before feeding to increase its hydrating capacity. One wet-down flake of hay can absorb 1-2 gallons of water. If you feed your horse well-soaked hay, you can make a real impact on his fluid consumption.
4. Offer fresh grass, watery bran mash and moisture rich trees such as carrots, apples or watermelon.
5. Allow your horse access to a clean salt block.
6. Combine 1 teaspoon salt with 2 tablespoons of applesauce. Put it in a syringe or de-worming tube and shoot it in her mouth. The salt should stimulate thirst.
7. Try squirting 1 tablespoon of corn syrup into her mouth. It will coat her tongue and compel her to drink.
8. If her water is very cold, try adding some warm water to the bucket.
9. Some horses do not like "different" water. If you're going on the road and can bring enough water from home, do so. If not, try to add a little apple juice, sugar beet water or apple cider vinegar to the water a few days prior to travel. It may help to disguise the "new" flavor.
10. Go for a ride! A 15-minute walk or a light ride will pilot thirst. Check with your vet before exercising if your horse is recovering from dehydration.
Exercising your horse after he consumes water will not make him colic. The horse's stomach empties very quickly in response to a water ingestion.
Moderate dehydration can be reversed by allowing the horse unlimited access to water and electrolyte supplementation
Severe and dangerous dehydration can best be reversed by giving electrolyte fluid intravenously. Contact your vet if your horse is strictly dehydrated.