Colic is the most common cause of pre-mature death in domestic
horses. It is also the most frequent cause of major veterinary
bills. However, the vast majority of colic cases could be
easily prevented through correct management. A study of the
existing research into this illness, including case studies
covering thousands of cases of horse colic, which has identified
the most common causes of colic, is the basis for the following
Ensure that the horse is on a regular deworming schedule.
All other horses which share the same pasture should be on
a synchronized deworming schedule, to prevent cross-reinfection.
If a horse has a heavy infestation of worms to start with
(e.g. if it has not been dewormed for a long time), then the
actual deworming itself can be dangerous, so one should use
a laxative to reduce the worm population prior to starting
a deworming schedule.
2) Food and Pasture.
Horses have evolved to eat and digest throughout the day.
Their digestive systems are based on 'continuous processing',
rather than periodic feedings (such as one finds in people
or large carnivores). Consequently, restricting them to feedings
only twice or even a few times per day is unnatural and places
a strain on their system. The ideal situation is for the horse
to spend the majority of its time on pasture, constantly eating
and moving. If this is not possible, it should be fed as often
as possible so that one comes as close as possible to the
'continuous processing' it has evolved for. One should never
feed food which has gone off (e.g. moldy, fermented).
3) Hay before Grain.
The horse digestive system is designed for 'high volume, low
calorie' food such as grass and hay; foods which are 'low
volume, high calorie' such as grain do not provide the volume
they require and can lead to various medical conditions (in
particular, ulcers). Consequently, use high-roughage foods
in preference to grains, unless there are specific reasons
otherwise (e.g. for intensive sports, grain may be necessary).
Furthermore, if one is providing both hay and grain, the
hay should be fed first. One reason for this is that by reducing
appetite with hay, it is less likely that the horse will 'bolt'
the grain (see 'bolting' below). Another reason is that there
is evidence that hay following by grain is digested much better
than grain followed by hay.
4) Soak Pelleted Food.
It is advisable to soak pelleted food before feeding to horses.
The main reason for this is that pelleted food expands in
contact with water, so if a horse 'bolts' a large quantity
of dry pelleted food, it can rapidly expand to an excessive
volume upon contact with fluids in the stomach. By pre-soaking
the pellets, the food is expanded before it is eaten. This
also reduces the rate at which the horse eats, reduces the
risk of choke and ensures that additional water is ingested
(for horses that are poor drinkers).
5) Excessive Feed.
Horses sometimes manage to get into the feed stores (e.g.
where you store grain or other high-calorie food) and stuff
themselves, which can result in colic. It is wise to keep
the room with feed locked, so that if a horse gets out of
its stable or pasture, it will not be able to get into the
If your horse 'bolts' (swallows without chewing) its food,
discuss options with your veterinarian. For example, with
hay pellets one can pre-soak them in water.
Ensure that the horse has access to water at all times. If
for some reason the horse has not had water for some time,
provide water in small amounts at first rather than allowing
it to drink a large amount at one go (particularly after exercise).
Likewise, if a horse has not been drinking for some time (horses
often refuse to drink during transport), ensure that when
it resumes drinking that it is gradual.
During winter, try to provide warm drinking water. A study
by the University Of Pennsylvania School Of Veterinary Medicine
determined that this increased water consumption by 40% (warm
water compared to near freezing water). As inadequate water
consumption is an important cause of colic (impaction colic),
providing warm water is advisable. Further, there is strong
anecdotal evidence that consumption of large quantities of
cold water in a short time (e.g. after exercise or after water
deprivation) can cause colic.
Colic can be caused by inadequate exercise (e.g. horse spends
most of day in stall), excessive exercise (especially if horse
is out of condition), or rapid changes in the amount of exercise.
Consequently, one should avoid these extremes.
Ensure that the horse does not eat its bedding, certainly
not in large quantities. If it persists in eating its bedding,
change to another bedding type which it does not eat.
10) Sand and Dirt.
Do not feed the horse on sand or dirt surfaces. Avoid stabling
the horse on sand or dirt. Do not leave a horse on over-grazed
11) Dental Care.
Correct and periodic dental care (e.g. annual examination,
with work if required) will minimize the risk of horses not
chewing their food properly due to dental pain.
A horse will sometimes lie down or roll so that its back is
against a fence or wall, with the result that it cannot get
up. Remaining in this position for a lengthy period risks
serious colic (e.g. movement of colon into a dangerous position),
so if one sees a 'trapped' horse one should quickly move it,
taking care to avoid accidental injury to oneself. Likewise,
a horse that lies down in a paddock sometimes gets its legs
trapped under or in the fence rails and needs to be freed.
Extreme temperatures (very high or very low) and rapid temperature
changes can cause stress on a horse, particularly those which
are weak (old or sick). During extreme weather, consider keeping
the horses in their stalls. Alternatively, there are a range
of horse jackets to protect from rain and/or cold. These should
be used if there are sudden extreme changes in weather or
if a horse is weak. In addition, although stables should have
good ventilation, they should not be drafty (in general, drafts
are more of a risk than simple cold).
Finally, one should be aware that horses do not react well to
change or stress. One should minimise these as much as possible;
if a period of change or stress is necessary (e.g. long distance
transport, changes to feed), one needs to monitor the horse
much more closely than normal and take special care of it. The
ways in which change can affect a horse negatively are numerous.
For example, horses will often stop drinking during periods
of stress or if they are moved to another area where the water
tastes different. As another example, adding or removing a horse
from a herd can upset the herd social dynamics, resulting in
About the Author
Dr. Stewart is the owner of Horse
Care. The above article is a small extract from his detailed
study at Horse Colic.