WSVMA Annual Conference
Equine Nutrition
Spokane Convention Center
Spokane, Washington
October 1-3, 2010
Steve Duren, PhD
Performance Horse Nutrition, Weiser, ID
Stephen Duren, MS, PhD, PAS
Performance Horse Nutrition
Weiser, ID
Biography:
Dr. Stephen Duren is an equine nutritionist based in the United States. As a consulting equine
nutritionist, Dr. Duren works with horse farms and feed manufacturers throughout the world
including LMF Feeds in the Western United States. Dr. Duren owns the consulting company
Performance Horse Nutrition.
Contact Email:
[email protected]
FEEDING NEGLECTED HORSES
Stephen Duren, MS, Ph.D., PAS
Performance Horse Nutrition
Weiser, Idaho 83672 USA
Starvation or malnutrition in horses can be caused by intentional neglect, ignorance, economic
hardship of owner, disease, dentition, pecking order, parasites, or seasonal variation in
availability of feed. Remarkably, horses can lose 30% or more of their body weight and still
survive. Horses in this condition will have very little muscle mass and will be very weak. Refeeding neglected or starved horses requires special attention and a sound nutrition program to
return them to a proper body condition. Even with the best of care some horses won’t survive,
especially horses that have lost 50% or more of their body weight.
When a horse is fasted, the body starts to breakdown stored fats and carbohydrates to use as
energy to maintain life. When these stores are depleted the body starts to derive energy from the
breakdown of protein. Initially the body breaks down protein from muscle causing muscle
wastage. However, this utilization of protein is not specific to skeletal muscle and can also
breakdown protein from vital organs such as the heart and gastrointestinal tract. The lack of
nutrition also depletes the body of vitamin, mineral and electrolyte stores and leads to a state of
salt and water intolerance.
Body Condition Score
Neglected or starved horses are generally in poor body condition. To quantify the
condition of horses, a body condition scoring (BCS) system is utilized. The most widely
accepted scoring system is the 1-9 system of Henneke and coworkers (1983). This system is
used to determine the fat stores by visually evaluating specific areas of the body such as the
neck, withers, tail head, ribs, shoulder, pelvic area and back. A horse with a BCS of 3 or less is
considered underweight, a BCS of 4-6 is considered ideal, a BCS of 7-8 is considered
overweight and a BCS greater than 8 is considered obese. The following is a written description
of the Henneke body condition scoring system with illustrations put together by the Japan Racing
Association.
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Re-Feeding Syndrome
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Neglected or starved horses that are being reintroduced to feed occasionally suffer from refeeding syndrome. Re-feeding syndrome occurs when a fasted horse eats a meal (generally high
in carbohydrate); insulin is released and causes glucose to be absorbed into the body cells, but is
also draws the electrolytes magnesium and potassium out of the bloodstream and into body cells.
The starved horse doesn’t have an adequate store of these electrolytes and their depletion can
lead to heart, respiratory or kidney failure and subsequent death. These horses will also retain
salt and water resulting in severe swelling. Generally the effects of re-feeding syndrome will be
seen between 3 and 5 days after the first meal, and many horses die within a few days after
starting a feeding program. Re-feeding syndrome can occur regardless of body condition in
horses that have been fasted for more than 5 to 10 days.
Feeding the Neglected Horse
The first step in re-feeding the neglected or starved horse is to determine the reason for the
weight loss. This veterinary evaluation will determine the presence of a medical condition
resulting in weight loss. If the horses’ weight loss is the result of a medical condition, this
condition will need to be corrected to facilitate weight gain. On the other hand, if the reason for
weight loss is neglect, economics or ignorance this also must be noted to successfully plan a refeeding program.
The re-feeding of a starved or neglected horse can be broken down into four phases. These
phases are days 1-3, days 4-10, days 10-14 and day 15 and beyond. The following outline will
provide feeding guidelines during the four re-feeding phases.
Phase 1- Days 1-3
Equine nutrition research has shown the safest way to start a feeding program for a starved horse
is to offer small frequent meals of high quality alfalfa hay. For our example, assume a mature
horse with an ideal body weight of 1000 pounds. This horse may have lost between 30% and
50% of its ideal weight. Start the feeding program by offering one pound of alfalfa hay every 4
hours. The amount of alfalfa offered per day for the first three days of re-feeding is a total of 6
pounds. This is far below the horses’ energy requirement, but most feeding problems with
starved horses are the result of feeding too much too soon.
Alfalfa is better than other types of hay because of its high composition of quality protein, but
also the major electrolytes. Because alfalfa hay is very low in sugar content, there are minimal
effects in regard to insulin response. Follow this feeding program for the first three days and
provide fresh, clean water at all times. If it is an older animal with poor or missing teeth, it may
be necessary to feed an alfalfa hay pellet or cube that must be soaked and made into a mash prior
to feeding. The horse should not be fed any grain during this stage of re-feeding.
Phase 2 – Days 4-10
If the horse tolerates the Phase 1 feeding program with no diarrhea or other problems, keep
increasing the amount of alfalfa hay fed and decrease the number of feedings. From day 4
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through 10, the horse should be gradually adapted to being fed 4 lbs of alfalfa every 8 hours.
This provides a daily intake of 12 lbs of alfalfa. This is a twice the amount of hay that was being
fed initially to the starved horse. Follow this feeding program for days 4-10 and provide fresh,
clean water at all times. If it is an older animal with poor or missing teeth, it may be necessary to
feed an alfalfa hay pellet or cube that must be soaked and made into a mash prior to feeding.
The horse should not be fed any grain during this stage of re-feeding.
Phase 3 – Days 11-14
If the horse tolerates the Phase 2 feeding program with no diarrhea or other problems, the
amount of alfalfa can be increased again. During this stage of feeding we attempt to get the
horse to consume 2% of its body weight in alfalfa hay. This hay should be divided into two
equal feedings. Depending on the appetite of the horse, this amount of alfalfa should be easily
consumed throughout the day. The feeding rates for horses with different body weights are
shown below.
Current Weight of Horse
600 lbs
700 lbs
800 lbs
900 lbs
Total Amount of Alfalfa per 24 hours
12 lbs
14 lbs
16 lbs
18 lbs
Follow this feeding program for days 11-14 and provide fresh, clean water at all times. If it is an
older animal with poor or missing teeth, it may be necessary to feed an alfalfa hay pellet or cube
that must be soaked and made into a mash prior to feeding. The horse should not be fed any
grain during this stage of re-feeding.
Phase 4 – Day 15 and beyond
After two weeks, the horse can be fed twice daily with the total amount of alfalfa hay provided
equal to 2.5% of the initial body weight. These feeding amounts are shown below.
Current Weight of Horse
Total Amount of Alfalfa per 24 hours
600 lbs
15.0 lbs
700 lbs
17.5 lbs
800 lbs
20.0 lbs
900 lbs
22.5 lbs
After 14 days introduction to pasture can begin with an hour of pasture access for three to
four days. Gradually increase pasture time over a period of 10 to 14 days and then daily or 24hour access can be allowed. Also, if alfalfa hay is not readily available and another type of hay is
more available or economical, the horse may be gradually changed to another type of hay over
the next two weeks so that alfalfa hay no longer is fed after four weeks into the feeding program.
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Grain Feeding
The horse’s digestive system is designed to digest fiber from hay and pasture. However, grain
concentrates offer a more calorie dense feed and provide the horse with nutrients to repair
tissues. Starting at day 15, add a small amount of protein, vitamin and mineral pellet. This pellet
will add the essential nutrients that have been depleted from the body. This low inclusion
supplement will help protect the digestive system from upset often caused by large meals of
grain. A good protein, vitamin and mineral pellet to utilize with alfalfa hay is LMF Super
Supplement (A). This product is designed to be fed at a rate of 0.1 lbs of LMF Super
Supplement (A) per 100 lbs of body weight. For the body weights of the horses utilized in the
previous example the amount of LMF Super Supplement (A) that should be fed is as follows.
Current Weight of Horse
600 lbs
700 lbs
800 lbs
900 lbs
Total Amount of LMF Super Supplement (A)
0.6 lbs
0.7 lbs
0.8 lbs
0.9 lbs
The dietary adequacy of this diet is shown below. In this example the horse is eating 2% of its
body weight in alfalfa hay along with 0.1 lbs of LMF Super Supplement/100 lbs of body weight.
Finally, the horse has access to a plain white iodized salt block.
At 21 days discontinue the LMF Super Supplement (A) and begin to add a more calorie dense
grain concentrate. The LMF Primetime (A) is a pelleted grain concentrate that will facilitate
weight gain. LMF Showtime (A) is a non-pelleted grain concentrate that will also help horses
gain weight. Begin by feeding only one pound of grain concentrate twice daily. Gradually
increase the amount of grain by adding one pound per day until feeding 0.5% of the horse's body
weight daily. The dietary adequacy of this diet is shown below.
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Feeding this amount of grain and plenty of hay will allow for a slow and gradual weight gain.
Bringing a starved horse to normal body condition will take three to six months, depending on
the level of weight loss. Incorporating commercial feeds that contain high amounts of fat will be
beneficial as fat is the most dense form of calories that can be fed to horses (1 cup of oil is
approximately equal to 2.5 pounds of cereal grains when considering energy content).
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