Signs and Symptoms of Dehydration in Horses

horse exam

Horses become dehydrated because of inadequate fluid replacement. The fluid is lost through sweating, respiration, and excretion. This may happen on long rides on hot humid days and the horse fails to meet the demands of hydration. Most horses weigh around 1,100 pounds and require 12 gallons of water each day to meet their basic needs. This water helps maintain digestion and blood volume in the horse’s body. But in other cases, sudden sickness that brings with it a decrease in thirst might render the horse dehydrated. Generally, you should keep tabs on your horse because dehydration can lead to kidney failure. Here are some signs and symptoms of dehydration in horses:

Elastic Skin

Dehydration leads to changes in several areas. But the most common way to check if the horse is dehydrated is through the skin. A dehydrated horse will have elastic skin. This is due to the loss of water from the skin. Use your thumb to hold the skin of your horse’s neck above the shoulder. In normal circumstances, the skin should snap back quickly. Once it is dehydrated, the skin will form a wrinkle when pulled or pinched and take five seconds to disappear.


If your horse is stiff when it is stretching, this may be a sign of dehydration. Since you regularly stretch your horse, you develop an understanding of how flexible it is. So if you notice any changes such as the stiffness of the horse, this may be a result of dehydration. The body acts as a huge water reservoir. So, a hydrated horse is very flexible during exercises.

Capillary Refill Time

A hydrated horse will have pink and moist gums. In fact, if you place your thumb on its upper gum for a second, the pressure point will be white but return to light pink within a second. If it takes longer, your horse may be dehydrated. Call your vet if you find out that the gums are red. This may be a sign of endotoxemia.


A hydrated horse is very vibrant and focused on each task. If you notice your horse is losing concentration at any task and appears tired, your horse may be dehydrated. Your horse may even quit eating and drinking water even after being exposed to hot temperatures. It is safe to assume the horse is dehydrated even though this may not be the case. Assuming dehydration is the safest approach. Consider contacting your vet if you notice this because your horse may be dehydrated or sick.

Check the Mucous Membrane

Give the inside of your horse’s upper lip a swipe. It should feel moist with saliva and shiny. Colors such as white or purple on its mucous membrane indicate signs of dehydration. But if it begins to feel dry and the eyes look sticky, this may be a sign of dehydration.

Once you have identified that your horse is dehydrated, your vet will try to encourage your horse to drink fresh portable water. If this fails, the vet will administer electrolyte solutions through the mouth of your horse and stabilize it. In severe cases, your vet will inject the electrolytes into its body.

If your horse has experienced any of these signs and symptoms, visit our Chaparral Veterinary Medical Center in Cave Creek, Arizona, or reach out to us today at (480)-595-8600 to schedule an appointment.