How I made my skinny horse fat

Anyone who follows my blog knows about my beautiful old paint mare, Sunny. She just turned 25, and has, with a couple of exceptions, always been skinny. I’ve known her for 12 years, have owned her for ten of those, and in that time I remember her being at a good weight exactly twice. Every other point in my long relationship with this mare has centered around trying to get some weight on her.

Looking for ways to help your skinny horse gain weight?

We tried everything: More grain. Less grain. Hay in a haynet. Hay on the ground. Beet pulp. Alfalfa cubes. Beet pulp mixed with alfalfa cubes. Seriously, there’s nothing we hadn’t tried. Well, nothing, that is, except the three things it turns out she actually needs to keep weight on:

  1. Free choice hay. We’re talking all-you-can-eat hay buffet.
  2. A good quality (and yummy) senior feed (Purina Evolution is her grain of choice).
  3. 24/7 turnout, with a cozy shelter and absolute control over whether she goes outside or stays indoors.

Sometimes we over-think this whole feeding business. With so many articles written by experts (real or self-professed), and so many different feeds and supplements and natural additives on the market, it’s not hard to see how we can get really caught up in the whirlwind of jumping from one fad to the next, and forgetting what it is that horses really need.

For a long time, I was stuck on the idea that I didn’t want to feed “processed food” (read: commercially-prepared grain) to my horses. I thought that if processed food isn’t great for humans, it likely also isn’t for horses. I have since realized that a good quality, balanced, age- and condition-appropriate grain (or supplement) is often necessary to give horses the macro- and micro-nutrients they really need.

And what do horses really need? Well, every horse is different (just like every person is different), and some horses thrive better on certain things than others. Before we get into why most of the “usual suspects” didn’t help Sunny gain weight, how about we take a look at what every horse needs, to some extent or another?

What Horses Live On:


Water is an essential part of every cell in your horse’s body. Up to 12 gallons a day or more is required for vital functions. Clean, fresh water should be available at all times, and in winter, cold water may need to have the chill taken off to encourage your horse to drink more.


Carbs come mainly in the form of grains, and provide energy. Plant fibre (from grass, hay and other roughages) is required for digestion.


Found in such sources as oilseed meals, alfalfa and (to a certain extent) some grains, proteins are essential for growth, repair and maintenance of the body. This is especially true for young horses and old horses (which we found out when we began to feed Sunny a proper senior feed with a little extra protein).


Fatty acids, such as those found in corn oil, wheat germ oil and the like produce extra energy, can help put weight on a poor doer, and, in small amounts, aid digestion (especially of vitamins).


Vitamins come from good hay, grain, sunlight and supplements, and aid all bodily functions.


Found in good hay, grain, salt and supplements, minerals build and maintain bone and tissue, and trigger natural bodily functions.

Determining How Much to Feed Your Horse:

Before you can figure out how much to feed your horse, you need to know at least these three things:

1. How much your horse weighs;

2. How much each of your feeds weighs;

3. What condition your horse is in (thin, soft, hard, etc).

Using a set of kitchen scales and your scoop (many prefer a coffee can or similar container to a feed scoop because you can easily mark it), determine how much a pound of each type of grain you feed is (you may find that a pound of sweet feed takes up more of the can than, say, a pound of barley).

To determine the weight of your hay, put an average-sized flake in a plastic bag. Weigh yourself on a digital bathroom scale, then weigh yourself holding the hay, and figure out the difference. If you don’t have a set of digital scales, most feed stores will weigh your hay for you. Most types of hay weigh between three and five pounds per flake.

You can weigh your horse using a weight tape, which isn’t an entirely accurate system, but will give you a good starting point and will help you keep track of changes. As a general rule of thumb, horses require 2 to 3 pounds of total food (grain and hay) per 100 lbs of body weight per day.  Thin horses or hard keepers may need substantially more, and fat horses, easy keepers or ponies may require a little (or a lot) less.

Always keep in mind that horses need to be fed according to work done, size, age, type and temperament. Ponies tend to make better use of their forage, and therefore require less. Many ponies, in fact, do very well on good quality hay alone. Our large pony, Stella, gets a handful of supplement pellets twice a day (mainly so she thinks she got dinner), and stays, shall we say, pleasantly plump on good quality hay in the winter and grass in the summer.

The harder a horse works, the more of his daily ration will need to be supplemented with grain. The average horse in good condition requires roughly 90% of his daily ration in roughage (hay) and 10% in concentrates (grain), and a good rule of thumb is to supplement the hay ration with grain at a rate of about 10% for each step up in activity level.

One caveat: leaving horses go without hay or grass in their bellies for extended periods of time (ie the “usual” routine of feeding a couple flakes of hay two or three times a day, and two large grains a day) is one of the leading causes of gastric ulcers. I strongly recommend free choice hay for (almost) all horses.

How I made my skinny horse fat


If you have a very easy keeper, you can use a slow-feed haynet or feeder so you can regulate the amount of hay they eat. Or, if you can’t do this (for example, at our farm, everyone shares the round bale and what one eats, they all eat), then you’re going to need to exercise those easy keepers a little more to keep them at a healthy weight. A grazing muzzle is another option.

For really fat ponies or horses with metabolic issues, your only option may be to keep them in a grass-free paddock and use a slow feeder.

Conversely, thin horses or hard keepers will require more food than an easy keeper. Remember, though, that just increasing the grain for a hard keeper is not always the answer. Changing the type of grain being fed, or even just adding more good quality forage, might work better. A thin horse being fed a lot of concentrates may just build extra energy, and actually lose weight trying to work that energy off.

So, what should we feed those hard keepers?

Let’s get back to those horses that are just plain hard to keep weight on. There are a few tried-and-true methods of getting a skinny horse to gain weight. Here are some that we tried, with varying degrees of success.

Once we figured out the “magic formula” for Sunny’s weight gain, we stopped feeding all of these, but if you’re struggling to get, or keep, weight on your hard keeper, these are definitely worth a try as additions to a balanced, age/condition-appropriate grain ration and good quality, free-choice hay:


Vegetable oil (or corn oil, soybean oil, sunflower oil – speak to your vet about the right one for your horse) is pretty much pure fat. It’s a great way of upping the calories in your horse’s food without increasing energy. It’s palatable, inexpensive (especially if you buy the great big containers at Costco), and has the added benefit of adding a nice shine to your horse’s coat. Start out with just a few caps-ful until your horse is used to it, and then add up to a cup a day to add cool calories to your horse’s diet.

Beet Pulp

Beet pulp is another great way to add some calories to your horse’s diet. Beet pulp sometimes gets a bad rap. Many people still think that it has too much sugar to be good for your horse, but remember that beet pulp is the by-product of sugar production – it’s the fibrous material left over after the sugar has been extracted from sugar beets. Most horses enjoy the taste of beet pulp (although for some, it is an acquired taste for sure), and it makes a lovely treat in winter if soaked in warm water.

NOTE: It is commonly believed that beet pulp must be thoroughly soaked (ie for 12 hours or more) before being fed, while others believe that this is unnecessary, and that the soaking time can be drastically decreased, especially if you soak it in warm water instead of cold. Speak to your vet about this, and decide between the two of you what is best for your horse).

Hay Cubes

Pound for pound, hay cubes are a much more expensive way to give your horse the forage he needs, but they are definitely a sensible way to add more bulk to your horse’s diet and if fed soaked until they are soft (which they always should be), they can also be a good alternative for an old horse who has trouble chewing hay itself.

The most popular types of hay cubes are alfalfa, and a timothy/alfalfa mix. Straight alfalfa cubes may give your horse a bit too much protein for senior horses. I find timothy/alfalfa cubes to be a more sensible option (again, this is a good conversation to have with your vet).

Obviously there are many other options for adding calories to your horse’s diet. I would always recommend speaking with your vet, or an equine nutrition specialist, if you’re not happy with your horse’s condition. Having said that, horses, just like humans, do not do well with “one-size-fits-all solutions, and what we realized with Sunny was that calories were not the main ingredient to her (lack of) condition. As with people, there seems to be a psychological component to weight loss/gain as well.

The Free Choice Lifestyle

Since moving Sunny home almost a year ago, there are a few things I’ve noticed. Now, we’re extremely lucky in that we have (read: have made a zillion sacrifices in other areas of our lives so that we could build) what we consider to be a perfect little horsey paradise in our back yard.

We had two particular issues with two very different horses: Sunny with her weight problems, and Stella with her ulcer issues. For us, what worked best was to build them a lifestyle that revolved around “free choice”. The choice to be indoors or out, the choice to be alone or together, and the choice to eat or not.

We have a small shed-row type stable with stall doors (that are for the most part never closed) leading directly to a “sacrifice paddock” (we sacrificed the grass in that area to instead build a mud-free, grass-free paddock where they spend the winter months with their round bale). Off the sacrifice paddock, via a cleverly-designed series of corridors and gates, are six different grass paddocks that remain closed off until late spring, and are carefully managed so that the horses have nutritious, lush grass from mid-May through mid-October.

With this set up, the horses make their own choices as to whether they stay inside or outside, and when they eat hay. And that choice seems to have made all the difference for Sunny.

how I made my skinny horse fat -


What we noticed at first…

Before Sunny came home, she was… well… kind of (really) neurotic. She had some pretty odd habits. She would walk up and down her paddock aimlessly for hours. She would all of a sudden run full tilt to the gate, then canter back and forth as though panicking. She would practically attack you at feeding time, like she was worried she’d never be fed again.

Sometimes she did fine on her own and other times she had a total melt-down if you took her neighbour out of sight for two minutes. She had headshaking episodes, you could always see the whites of her eyes, and she never, ever, ever seemed settled.

Once she and Stella moved home to their world of choices, we started to notice little things (long before we noticed any change in weight):

  1. Sunny was much more relaxed. She didn’t have cause to panic at the gate anymore because she could decide if she wanted to be in or out.
  2. She spent more time lying down.
  3. She spent a lot of time at the round bale, but she didn’t necessarily eat any more hay (all winter, she ate about the equivalent of half a bale of hay per day, which was actually less than she was getting at her previous digs).
  4. She was happy to see me coming with the grain bucket, but began quietly standing in her stall and politely waiting for me to bring it to her.
  5. I was able to slowly start to increase the amount of time Sunny could stay alone in the paddock, to the point that I could take Stella out for a ride and Sunny didn’t even seem to notice.

Lo and behold, when spring came, I put the weight tape around her and she had actually gained weight. Through the winter, a time when typically she would have lost condition!

I know a lot of you will be thinking well of course she gained weight, she had her head stuck in a round bale all winter… but bear in mind, as I said, she was actually eating less hay than she normally would. The difference, I believe, is that she could make the choice as to when she ate. She never worried about when her next meal was coming.

Sunny’s ability to come and go as she pleased was integral to solving the weight and behavioural issues as well. I know that a lot of horses will adapt to being stalled for a large part of their day/night. Horses are amazingly adaptable, generous creatures. But just because a horse can adapt, doesn’t mean that’s what’s best for them. I’m not saying that my way is the only way, but I am saying that my way has dramatically changed my horses’ lives for the better.

A Few Notes About “My Way”…

While we did encourage an outdoor lifestyle for the horses (and in fact, neither stall door was closed all winter), I have never made Sunny (or Stella, for that matter) choose between food or shelter. At all times during the winter, we kept full haynets in the stalls just in case the weather got too nasty for the horses to want to go outside and eat at the round bale.

We did find, for the most part, that they didn’t eat much indoors in the winter (and in fact, every three or four days, we would end up dumping out the leftover hay from the haynets into the round bale feeder and replacing it with fresh). The weather had to be pretty nasty, indeed, for them to not want to eat outside.

blanketing horses in cold weather

We also kept Sunny blanketed all winter. We didn’t want her to have to waste any of her precious calories on staying warm. Stella, on the other hand, grew a coat that would rival that of any wooly mammoth, and had a nice layer of fat to help keep her warm, so she stayed naked all winter. Interestingly, the only weather that kept them indoors was either a cold freezing rain-type event, or howling wind. The rest of the time, in freezing cold or snowy conditions, and then on those lovely sunny days we sometimes get in our Canadian winters, they chose to be outdoors.

Also during this time, we actually cut out all of the extras Sunny had been eating. Before moving home, besides her senior pellets, she was getting large quantities of beet pulp, alfalfa cubes and oil through the day. By the time spring came, we had cut out all of the additives. She now eats three pounds a day of Purina Evolution (senior feed), free choice hay, of course, and a good probiotic (we use OmegaAlpha Biotic 8). That’s it.

So, to come full circle, if you remember at the beginning of this post, I mentioned the three secrets to Sunny’s weight gain:

  • Free choice hay. We’re talking all-you-can-eat hay buffet.
  • A good quality (and yummy) senior feed (Purina Evolution is her grain of choice).
  • 24/7 turnout, with a cozy shelter and absolute control over whether she goes outside or stays indoors.

So you can see that, for Sunny, the quantity of food wasn’t ever really the issue. For her, it was mostly knowing that she could have food whenever she wanted it. And the ability to choose to be outdoors as much as she wanted to. That, coupled with a good quality senior feed, has made all the difference.

How i made my skinny horse fat

Sometimes less really is more. And sometimes weight isn’t as associated with food as you would think. Sometimes it’s all about creating a lifestyle that works for your horse, and then allowing them to be… well… horses.

Do you have a skinny-minny horse? What sorts of feeding or lifestyle changes have you found that helped?