A diet low in starch and high in fat is beneficial for draft
horses & ponies.
Feeding Draft Horses: The
Story and Photos by Beth A. Valentine, DVM, PhD.
horses and draft-light horse crosses have been around for a
very long time. In years gone by, these powerful and hard working
horses worked to build our cities and to produce, harvest, and
transport the food we eat and the supplies we need. Although
the age of the machine is upon us, working horses are definitely
still with us. Folks, who prefer working the forest or fields
with horses, rather than with machines, can be found in virtually
every country in the world. But the popularity of the draft
breeds has moved far beyond the field and forest. People are
discovering that drafts are incredibly versatile animals, with
the ability to be super trail horses and to excel as performance
horses in many different disciplines. Many times the first draft
horse becomes only one of several in the barn. As I like to
say, "you gotta love a draft!"
Years ago no one asked many questions about what is the best
diet for draft horses. Drafts, like most horses, were fed a
traditional diet of grain and hay. Aside from water, forage,
whether in the form of hay or pasture, is always the most important
part of any horse's diet. Remember that most horses should be
fed 2 - 2.5 percent of their body weight in forage per day,
so a 2000 pound draft can eat a lot of hay! But is hay or pasture
enough, and is grain the best option for needed extra calories?
Studies in the last ten years have taught us an enormous amount
about the nutritional needs of draft related (and many other)
horses. In particular, the focus has been on what to feed to
keep a horse's muscles healthy. After all, muscle is the reason
we have horses, especially draft horses. There is still a lot
to learn, but what we have found is that many drafts are "metabolically
different" than we expected, and that a traditional diet
of forage, or forage with supplemental grain is often not enough
to keep draft horse muscles healthy. Draft and draft related
horses that are not fed properly are at risk for developing
a muscle problem known as equine polysaccharide storage myopathy
(EPSM, also called PSSM and EPSSM), which is a fancy way of
saying that the muscle builds up glycogen and glycogen related
compounds rather than using them for energy. And drafts are
often stoic and don't show signs of the problem until it is
quite severe. Mild indications of EPSM include poor hind muscling,
stiff hind limb gait, abnormal muscle cramps leading to what
is called "shivers," poor performance, and a low energy
level. Some people think that drafts are low energy by nature,
but nothing could be further from the truth - try spending some
time at a draft horse pulling competition and you'll see! Older
drafts that develop a stiff hind limb gait are often misdiagnosed
as having "arthritis." An older draft that is reluctant
to canter may be considered "normal." So, subtle signs
of EPSM are often overlooked or misdiagnosed.
Severe problems related to EPSM include tying up (also called
Monday morning disease and azoturia), progressive muscle wasting,
and weakness leading to an inability to stand after lying down.
In fact, EPSM is a common reason why so many wasted drafts are
found at auctions, and many people have assumed the problem
was neglect or abuse. Owners who have "rescued" such
drafts find that simply feeding these horses a traditional diet
cannot solve the problem.
was discovered about 10 years ago that draft muscles are prone
to building up abnormal levels of glycogen. To prevent this
condition, we designed diets that relied on fat and fiber calories
rather than starch and sugar calories. The grains in the diet
were drastically reduced, and fat calories were added to provide
needed energy. Along with plenty of good quality forage, supplemental
vitamin E, and when needed, supplemental selenium, this diet
has been a life saver for many draft related horses. Often referred
to as the EPSM diet, this type of feeding not only treats affected
horses, but we believe it can help prevent this problem from
ever occurring. Draft related foals can be weaned onto a high-fat,
high-fiber, and low starch and sugar diet, along with supplemental
vitamins and minerals to help support healthy growth. Working
drafts have better muscling and more endurance on this type
of diet. And older drafts benefit from the high density calories
of fat. Fat provides calories that don't need to be chewed,
and reduces the risk of laminitis due to age-related pituitary
gland problems. So, the EPSM diet works for drafts of all ages.
How much fat are we talking here?
gelding exhibits one of the subtle signs of EPSM. Notice that
his coat is shiny so you know he is not being neglected, but
his hind end muscling is underdeveloped when compared to the
we are aiming to provide at least 20-25 percent of total daily
calories from fat and less than 15 percent of total daily
calories from starch and sugar. I should add that this would
be considered a low fat diet for people. Horses digest added
fat very well, and do not metabolize fat into the low density
lipoproteins (LDLs) that contribute to disease in people.
The easiest way to design an EPSM diet is to gradually decrease
starch and sugar intake and gradually introduce fat into the
diet. Increase the fat until the horse is getting at least
1 pound of fat per 1000 pounds of horse per day. Fat can be
provided in the form of plant origin oil (such as soy oil,
rice bran oil, corn oil, flaxseed oil, etc.). Two cups of
oil is 1 pound of fat. Feeds that are at least 10% fat and
also low in starch and sugar can also provide some of the
needed fat. You can calculate the amount of fat in these feeds
by multiplying pounds fed per day by the percentage of fat
in the feed. That is, 1 pound of a 10% fat feed provides 1
x 0.10 = 0.10 pound of fat.
are different types of fatty acids in different fat sources,
but at this point we have no indication that any type of fat
is any better than another when it comes to feeding drafts.
Whatever type of fat you are happy buying, that your horse is
happy eating, is the best fat. My only caution is that the entire
fat needs should not be provided by linseed (flax) oil, as at
high levels (about twice the EPSM "dose") this oil
can cause gastrointestinal irritation.
Many people find that this type of diet can improve even normal
appearing drafts, by providing safe calories that reduce the
risk of colic, laminitis, and possibly stomach ulcers, and by
reducing excess body heat production during exercise in hot,
humid weather. The latter is particularly important, as the
skin surface area to muscle mass ratio in drafts is much smaller
than in light horse breeds, and excess body heat can be a real
problem for heavily muscled horses.
an EPSM Diet
This Belgian mare was rescued from slaughter. Her severe muscle
wasting is indicative of EPSM.
Many people focus on the protein level of concentrated feeds.
Some know that about 10% protein is all an adult horse that
isn't working hard or being bred needs, and steer clear of higher
protein feeds. What many people don't realize is that the recommendation
for protein is for the horse's entire daily diet, most of which
is hay or pasture. Horses that are eating forage that is less
than 10% protein will need a higher protein concentrate. This
will be particularly important for young growing horses, for
broodmares, and for hard working horses. Without analysis it
is impossible to know the protein content of the forage, although
in general clover and alfalfa products are higher in protein
than grass. No one yet knows whether drafts need more protein
in their diet than light horses, but since they have more muscle
to maintain I'd rather err on the side of a bit more protein
than the horse might actually need.
Is too much protein bad for a horse?
There are many claims that excess protein causes liver and kidney
problems, or causes horses to be overly energized. Actually,
the only problems associated with feeding too much protein are
increased urine production that is higher in ammonia, and increased
body heat production during exercise. High ammonia levels can
be irritating to the respiratory tract, especially of foals
that are closer to urine-soaked bedding. Increased heat production
can be a problem for drafts exercising in hot, humid weather.
Feeding a fat supplemented moderate protein diet will help to
keep the horse cooler, especially in hot and humid weather.
Addition of electrolytes when the horse is working hard and
sweating a lot will be important to replace salts lost in sweat.
And, be sure to cool the horse with cold water and provide plenty
of water to drink after exercise. Studies have disproven the
ideas that cooling a horse rapidly and that letting a hot horse
drink water will cause problems with colic, laminitis, or tying
up. In fact, not cooling a horse and rehydrating it rapidly
can cause health problems.
Feeding an EPSM Diet
It takes time (just over a year in this case), but feeding an
EPSM diet can really make a difference.
what is the bottom line when it comes to keeping drafts healthy?
My best recommendations are: plenty of good quality forage,
a low starch and sugar and high-fat diet, plenty of vitamin
E and adequate selenium, access to plenty of clean water and
free choice salt, fresh air and exercise, and heaps of love
and attention. Try it, I think you'll like it!
Valentine is an Associate Professor at the College of
Veterinary Medicine at Oregon State University. Dr.
Valentine owns drafts with EPSM, and helps keeps them
healthy with diet and exercise. She is the co-author
of "Draft Horses, An Owner's Manual" published
by Rural Heritage www.ruralheritage.com |
of EPSM Diets
by Jill Haight
Feed has several low-starch and high-fat feeds that fit
perfectly into an EPSM feeding program. Perfect 10, Perfect
12 and Victory! are both high in fat and low in starch.
Seminole Senior and Spillers Hdf Pellets provide very
low starch levels and may be supplemented with Seminole
Ultra Bloom, Seminole Rice Bran Oil or Seminole Corn Oil
to increase the amount of fat in the diet. The following
are examples of diets that provide the recommended levels
of fat for working horses with EPSM when fed with recommended
amounts of forage:
2000# Draft horse on Seminole Perfect 10 & Seminole
Rice Bran Oil
10 pounds per day of Perfect 10 = 1# fat
2 cups of Seminole Rice Bran Oil = 1# fat
Total fat in diet is 2.0 pounds.
800# draft horse on Seminole Perfect 12 & Ultra
10 pounds per day of Perfect 12 = 1.2 # fat
3 pounds per day of Ultra Bloom = .6 # fat
Total fat in diet is 1.8 Pounds.
600# Draft horse on Seminole Victory! & Seminole Corn
8 pounds of Seminole Victory! = .64 # fat
2 cups of Seminole Corn Oil = 1
Total fat in diet is 1.6 pounds
Draft/Light Cross on Seminole Senior
8 pounds of Seminole Senior = .56# fat
¾ Cup of Seminole Rice Bran Oil = .75# fat
Total fat in diet 1.3 pounds
1000# Draft Pony on Spillers HDF Pellet & Seminole
Rice Bran Oil
6 pounds of Hdf Pellets per day = .3# fat
1.5 cups of Seminole Rice Bran Oil = .75# fat
Total fat in diet = 1 pound
To learn more about these Seminole Feed products visit