Last Updated on December 28, 2021
At some point in a horse’s life, you might find that he does not drink as much water. This could be for a variety of reasons, including old age, ill health, or high levels of stress and anxiety. If you are worried that your horse does not have access to water, it is important to know how long horses can go without drinking water.
It could also be the case that your horse cannot drink water for some reason – maybe because of a medical problem or due to management restrictions. In this case, how long is it safe for horses to go without water?
How Much Water Do Horses Drink A Day?
To understand how long horses can go without water, firstly we need to understand how much horses drink. This varies widely for several reasons, as we shall find out.
Horses need to consume a certain amount of water each day to keep healthy. In veterinary terms, this is calculated as 50 milliliters of water per kilogram of body weight every 24 hours. So, an average 500-kilogram horse needs 25 liters of water per day just to survive.
However, it is not quite as simple as this! This is the bare minimum amount of water a horse needs to maintain its basic body functions.
Many other factors also affect the amount of water a horse drinks a day, including:
Size Of Horse
It may seem obvious, but larger horses need to drink a lot more water! A miniature horse may only need 5 to 10 liters of water per day, whereas a large draft horse could drink up to 100 liters every day.
In hot weather, horses will need to drink more water. This is because they lose a large amount of water through sweating, in an attempt to keep cool.
The food your horse eats may or may not contain water, and this will affect how much your horse needs to drink. For example, grass contains 83% water, but hay contains less than 18% water. A horse fed entirely on hay will drink much more water than one out at grass.
During intense exercise, horses lose a lot of water through sweat and respiration. A fit and active horse will drink a lot more water than one that does very little exercise.
As we can see, many factors affect how much water a horse needs to drink. A horse that lives out on the grass in a cool climate and does very little exercise will drink 25 to 55 liters of water per day. A horse living in a hot country, with an intense exercise regime and that eats only hay, may drink at least twice this amount.
How Long Can Horses Go Without Water?
One of the most important rules of caring for horses is to allow them access to clean, fresh drinking water at all times. Water is one of the most essential nutrients for life, and without it, a horse will quickly die.
After 48 hours without water, a horse may start to develop health problems. The severity of this depends again on the horse and its individual circumstances. A horse that can access lush grass is able to survive for longer without water than one which eats only dried hay.
What Happens If Horses Go Too Long Without Water?
If a horse goes too long without water, it will start to become dehydrated. This means that the body does not contain enough water to function normally.
Water makes up an incredible 65% of your horse’s body and is essential for life. When a horse does not have access to water, it will quickly start to become dehydrated.
When dehydration occurs, the horse is not able to maintain its normal bodily functions. The blood becomes thick and viscous, making it harder for the heart to pump it around the body. Levels of electrolytes in the body will also become imbalanced, leading to cellular dysfunction and death.
If left untreated, dehydration will quickly lead to death. A dehydrated horse may be too sick to drink water, so prompt veterinary attention is required to rehydrate the horse.
Read more about Miniature Horse Lifespan Facts And Figures Revealed!
How To Tell If A Horse Is Dehydrated
A dehydrated horse may show a wide range of clinical symptoms. As a horse owner, you must learn to recognize these signs of dehydration. The sooner a horse with dehydration is treated, the better chance it has of surviving.
A dehydrated horse will be lethargic and depressed, and the eyes will appear sunken and dull. The inside of the mouth will be dry, and any saliva will be thick and gelatinous. If a horse is dehydrated the flanks will be tucked up and he will pass very little urine or feces.
When dehydrated, the horse may also show signs of fatigue and may start to tremble. The muscles will become stiff and sore, particularly if dehydration occurs during exercise. The heart rate of the horse can also be elevated, and the heart itself might start to beat irregularly.
The skin pinch test is a quick and easy method to judge if a horse is dehydrated. Take a fold of the horse’s skin on his neck and pinch it upwards. Release the skin and observe what happens.
In a healthy, hydrated horse, the skin will immediately pop back into its original position. If the skin remains in a ridge or takes more than a few seconds to return to position, then the horse is suffering from dehydration. If you are concerned that this is happening to your horse, call for veterinary help immediately.
So, as we have learned, horses can go without water for up to 48 hours, but this is very dangerous for the animal. Horses should be able to access fresh, clean drinking water whenever they need it. Reduced access to water can cause health problems including colic and life-threatening dehydration.
We’d love to hear about your experiences – do you find that your horse drinks very little water when he is out grazing? Or maybe you are worried that he does not drink enough water in hot weather? Add a comment below this post and we’ll get back to you!
Kate Chalmers is a qualified veterinary nurse who has specialized in horse
care for the vast majority of her career. She has been around horses since
she was a child, starting out riding ponies and helping out at the local
stables before going on to college to study Horse Care & Management. She
has backed and trained many horses during her lifetime and competed in
various equestrian sports at different levels.
After Kate qualified as a veterinary nurse, she provided nursing care to the
patients of a large equine veterinary hospital for many years. She then went
on to teach horse care and veterinary nursing at one of the top colleges in
the country. This has led to an in-depth knowledge of the care needs of
horses and their various medical ailments, as well as a life-long passion for
educating horse owners on how to provide the best possible care for their
Kate Chalmers BSc (Hons) CVN, Dip AVN (Equine) Dip HE CVN REVN RVN A1