Horses and water - it's never easy
 
HorseFeathers Veterinary Service, PLLC 

It is truly an age old problem to be sure that enough water is getting into the horse.  Being horses, they are not always the most cooperative.  If you are used to working with dogs, the possibility of inducement comes to mind.  It may come to mind with the horse as well, but, as you will find out, it doesn't work.  Doesn't work at all.

Horse Physiology

One of the reasons that horses and water are a concern is how the horse is built.  Horses are enormous creatures with enormous muscles.  They are a delight to ride or just to watch them chase each other and play.  The dickens of it is that the horse sweats isotonically.  That is to say, when the horse sweats, she loses water and electrolytes in a normal body mixture.  The horse has chemoreceptors in her carotid arteries.  These chemoreceptors check the blood passing by for too much sodium, too little potassium, etc.  Since the horse sweats isotonically, all these markers being checked by these chemoreceptors maintain a normal mix.  It is not the case that the horse's blo0d becomes thick with electrolytes and low on fluids and the horse is stimulated to drink.  The horse is stimulated to drink in a much more subtle manner and sometimes not until the conditions become dire.

Also, horses are living longer these days.  Veterinary Medicine has progressed and conditions that would cause the demise of these beautiful creatures are now treatable conditions.  There are more situations to watch for in the older horse with various compromised systems.  Markers become more subtle and systems become even more fragile.

Winter and Horses in North Carolina

Here in North Carolina, it rarely gets to the freezing mark for more than a day or two.  This year (2008) has already been different.  There were days that were in the 60's and a string of days in the teens and low thirties.  What this means to the horse owner is that the water trough will freeze and stay frozen.  Some horses don't really care how cold their water is and will drink clean water quite readily.  Other horses (they don't wear a sign so you can't tell by looking at them) will drink only enough to survive if the water is too cold.  Often they will become remarkably dehydrated, refusing to drink water with large chunks of ice floating in it. 

 Consider the horse that is getting up in age.  Teeth that were once sparkly clean and perfect have suffered the ravages of age and the idea of putting ice water on a cracked tooth becomes a very effective negative reinforcement.  And, since horses lose water in an isotonic manner (see above), they can become very dehydrated before it becomes noticed in the winter.  Your veterinarian will be able to help you determine if your horse is adequately hydrated.  Just to 'see him drink' is not at all the same as having him drink enough to stay healthy.

A horse in a paddock and stall is basically locked in to what could be a heaven or not.  The only option for water is what you the caretaker offer.  It is a good idea to have some benchmark of how much your horse drinks on a normal, regular, not much happening day.  Then, with that in mind, you can make a knowledge-based guess on whether he is drinking enough.  Just in general, that amount is more than you think.  A horse is a big animal.

In the winter, there are trough heaters that prevent the water in the trough from freezing.  Often this is enough to allow the horse to drink as needed.  For those poor souls with tooth problems or gum problems, water at 40 degrees F is just too cold.  Older horses will more readily drink warm (warm to the touch of your hand) water when offered.  The problem here is hauling water.  For those who haven't had the pleasure recently, water is heavy.  And, for some reason, it wants to spill.  But,  the horse needs to drink the same amount of water when it is winter as when you measured above.  Else, you risk dehydration colic.  A horse, for all his magnificence, is a very delicate creature.

Summer and Horses in North Carolina

The summer here in North Carolina gets hot.  A horse cools himself by sweating, often profusely, and ultimately, panting.  The amount of water consumed by a horse per day in North Carolina in the heat of the summer is huge.  Now, you still want to know what consumption is normal for your horse. 

One problem you will face is keeping the water trough clean.  In 100 degree weather, in the sun, all sorts of microflora grow in the water trough.  And, they grow quickly.  It is common to see a trough with some sort of reddish, greenish slime attached to the sides of the trough.  Doesn't matter what the identity of these microbes are, empty the trough and scrub it till it's clean.  There is an on the farm test for water - the 'would you drink that?' test.  

The horse will easily get dehydrated if the only source of water is that trough with the multicoloured slime on the sides.  He will take a sip when he cannot stand it anymore, then only just a little.  Remember, he is a your responsibility and this is his only choice for any hydration. The solution here is both easy and hard. The easy part is that all you have to do is empty the trough and scrub it sparkling clean.  The difficult part is that it is hard work to do that.  In North Carolina, that procedure has to happen at least once a week.  More often if the trough looks dirty . . . would you drink that?

HorseFeathers Veterinary Service, PLLC 1