Large Animal Theory I
Equine Nutrition
Equine Nutrition – Anatomy
Review
• Remember, while horses eat similar foodstuffs
as ruminants, they are monogastric
• “Hindgut Fermenters”
• Fermentation takes place in the cecum, not
the stomach.
• Besides having a large cecum, their digestive
system is similar to ours only larger
Equine Nutrition – Anatomy
Review
Equine Nutrition
• Compared to the rest of the horse's digestive
tract, the stomach is quite small.
• The stomach can't handle a lot of food at
once, but if they don't eat enough, gas can
build up and cause colic
• Therefore horses need to eat several meals
throughout the day to maintain digestive
health
Equine Nutrition - Colic
• Colic is not a disease but a general term
indicating abdominal pain
• Not solely a result a issues with the GI tract –
other diseases can lead to colic as well
• In relation to nutrition, these are the most
important factors in colic prevention:
– Frequency
– Quantity
– Quality of feed
Colic Cont’d
• Check foodstuffs for mold, dust, or signs of spoilage
• Check feed, stalls, and pastures for foreign objects
that may be ingested and remove them
• Avoid grazing in sandy areas – can cause “sand colic”
– Buildup of sand in the intestinal tract
– There can be as much as 150 pounds of sand lying
in the bottom of the horse's belly.
– Blockages or ischemia can occur
– Intestinal rupture = death
Colic Cont’d
• If horses are fed an imbalanced diet that
can also lead to colic
– Too much concentrates (grain)
– Too many minerals (improper supplements)
– Too much alfalfa (greater than 50%)
• Too much alfalfa can also lead to enteroliths
– Built up mineralization in digestive tract
– Can be passed in feces
– May get too large and need to be surgically
removed
Enterolith
• http://panoramaequine.com/case_studies_en
terolith_sx.htm
Signs of Colic
• Pawing the ground the ground with its front feet
• Restless, lie down and roll frequently and look or bite
at its abdomen.
• More severe colic: will roll and may lie on its back to
relieve intestinal pressure.
• Very severe colic: will throw themselves to the ground
and roll violently.
– These horses can be dangerous to work with until properly
sedated.
• Lack of gut sounds or very increased gut sounds
Equine Nutrition
• Most digestion and absorption takes place in the
stomach and small intestines.
• Some absorption takes place in the cecum and colon.
• Microbial digestion occurs in the cecum.
– Vitamin B complex and volatile fatty acids are produced
here.
• Energy is provided by the breakdown of starch and
other soluble carbohydrates.
Equine Nutrition
• Horses normally eat grass
and other range forage.
• Feeding cost is the greatest
single cost in keeping a
horse.
• The main difference
between feeding horses
and livestock is the
multiple uses of the horse.
Equine Nutrition
• Meeting nutritional needs of horses is a major factor
in determining their efficiency and years of service.
• Horses can typically be placed into one of the
following groups when utilizing a feeding plan:
1. Maintenance
2. Growth
3. Reproduction
4. Production
Equine Nutrition
• Production can be further broken down to:
– Gestation
– Lactation
– Foals
– Maintenance of adults
Equine Nutrition
• Broodmare
– Typically the first 7 months of pregnancy do
not significantly change nutritional
requirements (typically the same as
maintenance).
– From the 8th month to parturition the
energy requirements increase 20 – 50%.
– Protein requirements increase 20 – 25%
from the 8th month on.
Equine Nutrition
• Broodmare cont’d
– The calcium, phosphorus, vitamins A & D, and riboflavin
levels need to be adjusted for gestation and
lactation.
– Lactating mares need 50% or higher increase in
energy requirements.
– The average mare produces 20 – 25# of milk daily
for the first 2 – 3 months. Milk starts to wane at
this point until the foal is weaned (usually around
6 months).
Equine Nutrition
• Foals
– Foals receive almost all of the nutrients they
need from their mother for the 1st six
months of life.
– Should begin creep feeding around 3 months
of age, however most foals will begin
nibbling on grain and hay by 3 weeks of age.
– Generally 1# of creep feed/ month of age/
day not to exceed 6# daily.
Equine Nutrition
• Weanling
– After weaning a good starting point is 1 – 1.5# of
grain/ 100# of live weight and 1.5 – 2# of hay/
100# of live weight.
Equine Nutrition
• Maintenance
– Healthy adult horse’s need good quality grass or
legume hay
– Free choice water
– Phosphorus
– Trace mineral salt
– The energy requirements of an adult horse is
related to the intensity of work performed.
Equine Nutrition
• Maintenance cont’d
– Energy requirements can be made based on
either observation (BCS and maintaining BCS)
or calculation.
– Protein requirements for work are minimal and an
increased work load does not increase protein
requirements (typically).
– Need calcium and phosphorus in diet.
Equine Nutrition
• Hospitalized horses are at risk to developing proteincalorie deficits, hypermetabolic stress, or catabolic
wasting.
• GI patients may present one of the biggest
challenges.
• These patients need increased protein, calories, and
micronutrients, but also have decreased GI motility.
Equine Nutrition
• Good quality legume hay typically contains
around 14-18% crude protein.
• High quality grass hay typically contains 7-12%
crude protein.
• Cereal grains typically contain 8-12% crude
protein.
• Ideally the calcium/ phosphorus ratio should
be around 1.2-1.6:1 ratio.
Equine Nutrition
• Salt should be provided free choice.
• Copper, zinc, and selenium are needed in very
small quantities.
• The most common vitamins added are A,D,
and E.
• Vitamin A can naturally be found in green
forages and properly cured hay.
• Vitamin D aids in the absorption and
utilization of calcium and phosphorus.
Equine Nutrition
• Vitamin D can be found in sun cured hay and
cod liver oil.
• Vitamin E can be found in sufficient quantities
in the horse’s normal diet.