Skinny Horses


Yin and yang food

For every yin, there is a yang.  I wrote an article on fat horses – here’s one on skinny horses.

Skinny horses are the other side of the coin from fat horses.  Skinny horses are a little bit – I emphasize, a little bit – more complicated than are fat horses, mostly because if your horse is skinny, it’s not necessarily your fault (deep breath).  It could be your fault, it’s usually your fault (in one way or another, and usually not intentional), but it’s not always your fault.

Before we get started, let’s talk about what we’re shooting for.  Ideally, you want your horse to be thin enough where you can easily feel his ribs, but not so that you can see them. That said, a horse can be a bit thin and still be very healthy.  In fact, it’s better for a horse to be a bit thin than it is to be a bit fat – look at racehorses and endurance horses, for example.  On the other hand, lots of horses are kept too fat.  Try to shoot for the “can’t see the ribs but can feel them” target for most horses; if you can feel his ribs but not see them, he’s NOT skinny, no matter what the person in the stall next to you says.

Anyway, here’s the question.  If your horse is to thin, what’s the number one reason?

Drum roll, please….. Answer:  He’s not getting enough to eat.

Anticlimactic, I know.  Still, skinny horses are usually skinny simply because they aren’t getting enough to eat relative to what they need to eat.  That, of course, brings up another question, that being, “How much do horses need to eat?”

And the answer is, “It depends.”



Slow metabolism

1.  Your horse’s metabolism.  You have friends that can eat and eat and eat and eat and don’t seem to put on a pound.  You are envious of them.  (In fact, you are so envious of them that you sometimes wonder why you keep them around as friends, but I digress.)  There are horses like that, too.  Their temperament, or metabolism, or something just makes it hard for them to put on weight.  Those horses need to get more than what you’re currently feeding them.


Michael Phelps. You’re welcome.

2.  What your horse does.  Michael Phelps, the Olympic swimmer, eats something along the lines of 12,000 calories a day when he’s training.  CLICK HERE if you don’t believe me. You can’t eat 12,000 calories a day, and not gain weight (it would be hard to eat 12,000 calories a day under any circumstances).  But Michael exercises five hours a day.

Certain activities increase the horse’s needs for calories.  An endurance horse, for example, who goes 50 or 100 miles in an event, needs lots and lots of feed simply because exercise requires lots and lots of calories.  Lactating mares need lots more feed because producing milk for their foals requires lots of calories.  So, if your is doing something that requires extra calories, and you’re not giving them to him, he’s going to be thin.

3.  What you’re feeding him. If you had an unlimited supply of celery, and that’s all you ate, you’d starve to death.  You could eat and eat and eat all of the celery you wanted, and you’d eventually kick the bucket.  That’s because celery is mostly fiber and water.  If you ate 1 kilogram (2.2 pounds) of celery, you’d satisfy less than 10% of your daily caloric requirements.  And, you’re stomach would get full before you could eat enough anyway.


Not for weight gain

Same with horses.  Some feeds, such as oils and fats, have lots of calories in them; they have a high caloric density.  A pound of rice bran supplies a good amount of extra energy for your horse.  Some feeds, such as oat hay, have much fewer calories per pound than, say, alfalfa hay.  If you’re trying to fatten up a horse on a diet of oat hay, it’s generally not going to be easy.

What this all means is that if your horse is skinny, you may need to give him feeds that are more calorie dense, that is, feeds that have lots of calories in them relative to the amount that you have to feed.  If you were skinny, and you wanted to gain weight, you wouldn’t load up on rice cakes (hopefully), you’d eat ice cream, or chocolate cake.

fat bomb

Calorie density, deliciously illustrated

In that same vein, you have to be able to get the calories in you horse.  If your horse is skinny, simply throwing him a bit more hay may not do the trick – his stomach might fill up before he can get enough extra calories.  You may need to feed him a higher calorie hay (substituting some alfalfa for grass hay, for example), or add fats, or, in some cases, even grains.

4.  If there’s some sort of problem.  So, here’s a big difference between skinny horses and fat horses.  Sometimes horses are skinny because they have health problems.  Not often, mind you, but sometimes.  If you think that you’re feeding your horse enough – or more than enough – then it’s probably worth getting your veterinarian out to take a look.  If your horse is skinny, your veterinarian might check to see:


Don’t look here, if it’s a gift

If he has bad teeth.  Honestly, bad teeth are a pretty unusual cause of weight loss, unless your horse is old, and missing teeth.  I wouldn’t count on your horse putting on a bunch of weight just because you had his teeth floated, however.  It’s usually more than that, but it’s definitely worth checking.

– If he is parasitized. That’s another pretty unusual one, especially now, when many people seem to want to deworm their horse so often.  It takes a whole lot of worms to make a horse lose weight.  Sure, that could be your horse, but if you’re at all conscientious, parasites are probably not the problem.

sick liver

Sick liver (rarely seen)

– If he has some sort of disease.  Every once in a while, you’ll run across a horse that has a medical problem that is causing him to lose weight.  Maybe his kidneys aren’t working efficiently, or his liver is diseased.  It’s possible – just unlikely.  Still, if your horse seems to be defying all efforts to get him to put on some weight, it’s certainly not a bad idea to get him examined, and perhaps submit a complete blood count and body chemistry tests to make sure things are working.

But here’s the thing.  After you go through all of that, the number one, mostly likely cause of your horse being skinny is that he’s not getting enough to eat.  I realize that this is not the answer you wanted to hear – it’s sort of like finding out that the dryer wasn’t working because it wasn’t plugged in.  You’re happy that you can get it going again, but, really, finding it it was so obvious is a bit embarrassing – and especially after you called the repairman.

Anyway, if you’re wondering if you’re feeding your horse enough, your question is…


Well, let’s go through a checklist.

1.  KNOW THE FEED RULES.  And, for your convenience, you can CLICK HERE to see the feed rules.

2. FEED AT LEAST 1.5 – 2.0% OF YOUR HORSE’S BODY WEIGHT IN FEED.  Look, I don’t really like math either.  But if you’ve got a skinny horse, you really should do some measuring.

weight tape

Where you put a weight tape

First, get an estimate of your horse’s weight, with a weight tape, or a scale.  Let’s say your horse is a typical Quarterhorse, weighing about 1000 pounds.  That means that he is going to need 15 – 20 pounds of feed per day, just to maintain his normal weight.  That’s what he needs to keep the lungs working, the heart pumping, etc., etc.  If you want him to do some work, you’re probably going to need more.

Second, weigh your feed.  Things such as “flakes” or “coffee cans” are not official units of measurement.  Get a feed scale (if you don’t know where to find a feed scale, send me an email, I can get you an almost indestructible one).  Then, weigh the feed before you feed it.  It’s a simple step that will 1) Ensure that you’re giving enough feed, and 2) Ensure that you’re not giving too much feed.*

horse at dinner table3.  Make sure he’s eating all  you give him.  I don’t know how many times I’ve seen three horses in a pasture, two of which were fat as a pig, and one on which you could scrub clothes on his ribcage.**  Mr. Bones will thank you for feeding him separately.

4.  Make sure he’s getting fed all that he needs, considering everything that you’re asking him to do.  If your horse is big, or anxious, or pregnant, or exercising a lot, you may simply need to get some more feed into him or her beyond what would be needed if your horse wasn’t doing any of those things.  Don’t worry – you’re horse won’t mind.  They love to eat, and aren’t worried about getting fat.

Oh, and one other thing, if you’re not the one who is feeding your horse, and your horse is skinny, make sure that your horse is getting what you’re being told he’s getting.  I’m not trying to point any fingers here, but you never know.

ONE LAST THING – Horses almost never get skinny because they lack supplements.  If you want to put on weight, what, you’re going to load up on the Flinstones Chewables®? (At least I think it’s a trademark – better safe than sorry).  Skinny horses generally need to be supplemented with just one thing – calories.

Look, a skinny horse is skinny for a reason – you (perhaps with the assistance of your veterinarian) just have to figure out what that reason is.


* Feeding too much feed is a waste of money.  Hay is expensive enough.  Your horse may enjoy tossing his hay up in the air, and walking around on it, but you’re the one who gets to pay for his entertainment.

washboard**  For those of you who haven’t seen what an old washboard looks like, here’s a picture.

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