Contemplating Colic

By Sarah Gee
©Voice, November 2006

Of all the species of domestic livestock, horses are the most prone to colic. The anatomy of a horse’s digestive tract, its digestive nature, and the management practices imposed by man seem to contribute to its occurrence. Colic is a general term that refers to abdominal pain; it is not the name of a specific disease. Colic can be caused by a variety of agents and conditions and it can be very difficult to diagnose. The following are some of the agents and conditions frequently implicated with colic:

Conditions Frequently Implicated With Colic
Parasites.
Over-consumption of high energy feeds.
Abrupt changes in diet.
Side effects of certain medicines.
Administration of a dewormer when a horse is overloaded with parasites.
Ingestion of poisons, toxins, or molds.
Stress caused by transportation or changes in daily routine, housing, etc.
Formation of a large mass in the large intestines.
Inadequate water consumption.
Poor quality feeds.
Infections elsewhere in the body.
Conditions affecting the locomotor system, like laminitis.

In addition, a number of digestive tract disorders result in colic. All areas of the digestive tract can be affected. The following is a list of disorders that can cause colic:

Disorders That Can Cause Colic
Ulcers, impactions, tumors, and distension of the stomach.
Impactions, enteritis, displacements, infarctions, and obstructions of the small intestine.
Impaction, perforation, torsion, and infarction of the cecum.
Distension, impaction, displacements, strangulation, and obstruction of the large colon.
Obstruction and impaction of the small colon.
Peritonitis – inflammation of the abdominal cavity.

Since even the most well managed horse is likely to experience colic at some point, it is vitally important that all horse owners be able to recognize the most common signs of the affliction. The following are some of the more typical behavioral signs exhibited by horses suffering from colic:

Behavioral Signs Exhibited By Horses Suffering From Colic
Off feed or changes in eating habits.
Circling, laying down, rolling, laying down and getting up frequently.
Pawing.
Violently rolling.
Looking back at the flank or abdomen, kicking at the abdomen.
Stretching out and standing for long periods.
Acting anxious.

Along with these behavioral signs, horses may also exhibit physical signs of pain. The following are common physical signs associated with colic:

Common Physical Signs Associated With Colic
Elevated resting heart rate (a rate over 50 beats per minute may indicate moderate to severe pain).
Purple, dry gums (suggests severe colic).
Slow capillary refill time (test by pressing on the gums, if it takes more than a couple seconds for color
to return there’s a problem).
Lack of gut sounds (assess by listening over the flank area).
Reduced manure output.
Sweating.
Trembling.

The severity of colic can be categorized as mild, moderate, or severe. Not all behavioral or physical signs occur with every bout of colic, and the degree they are displayed is expected to vary. The ability of the horse owner to judge the severity of a case of colic requires experience and veterinarian advice. Immediate consultation with your veterinarian is recommended if in doubt at any point or if signs indicate that the colic episode is moderate to severe.

Veterinary treatment of colic can be categorized as medical or surgical. Routine medical procedures include rectal examination, accessing vital signs, passage of a nasogastric tube, administration of laxatives, and administration of medications for sedation and pain relief. More complex procedures include hospitalization for blood and abdominal fluid tests, supportive therapy and medications, and continuous monitoring and evaluation. Surgical procedures can involve the positioning of a displaced section of intestine, decompressing a gaseous formation, manipulating an obstruction, removing the contents of the stomach, cecum, or intestine, or removing a compromised section of intestine.

While totally eradicating colic is not really feasible, lessening its likelihood is a goal that is obtainable for every horse owner. The following are some practical steps that can be taken to reduce the chances of colic:

Steps That Can Be Taken To Reduce The Chances Of Colic
Do not overgraze pastures and paddocks.
Provide a clean, adequate, and abundant source of fresh water at all times.
Feed on a regular schedule from day to day.
Do not feed moldy or spoiled hay or grain.
Provide adequate long stem roughage in the diet.
Keep stalls, pastures, and paddocks free from foreign objects that the horse might ingest.
Limit access to unknown or toxic weeds.
Put all horses on a regular, properly designed deworming program.
Made adjustments in housings and conditioning as gradual as possible.
Regularly monitor the horse’s overall well being.

References:
Colic in Horses, Cooperative Extension Service, University of Kentucky Bulletin #ASC-128. Freeman, David W., PhD, and
Carolynn MacAllister, DVM, Understanding Colic in Horses, Oklahoma Cooperative Extension Service Bulletin #F-3921.