Colic in Horses: Types, Triggers, Symptoms and Prevention

Aug 8, 2011
Elizabeth Batt

Gastrointestinal fistula research has advanced colic treatments - Todd Huffman

Colic scares the life out of every horse owner, but knowledge is power. Learn about the different types of colic and the strategies for prevention.

In 1986, the Morris Animal Foundation reported that colic is the number one killer of horses and the primary fear of many horse owners. Colic has a rapid onset and multiple causative factors that are difficult to pin down. In fact, the majority of colic cases in equines lack any specific root cause. It is this fear of the unknown that fills owners with dread. Educating oneself to the triggers, types and symptoms of colic is an absolute necessity for every horse owner.

What is colic and why are horses prone to it?

Colic simply means abdominal pain. What actually causes the pain can be something as simple as a change in weather or an ingested trigger such as a different diet. The physical characteristics of the horse's gut plays a large role in colic predisposition. For example, the horse actually has a small stomach because it is a natural grazer used to taking in food over a long period of time which is then digested gradually.

Something as simple as bulk feedings then, ask the horse's digestive system to cope outside of its natural capabilities and colic happens. Unlike humans, the horse cannot vomit when something upsets its stomach, so whatever it ingests has to be able to pass through the gut.

It isn't always food intake that causes colic. The Department of Equine Sciences at the University of Kentucky, lists several triggers that have the potential to cause colic. These are:

Weather changes
Feed changes
Changes in amount and frequency of feedings
Overexertion or chilling of the horse
Intestinal obstruction
Internal parasites
Deworming medicines (particularly in heavily infested horses)
Infections and lameness
Various forms of overgrazing, too much green grass, sand colic etc.

This multitude of potential trigger objects means that even the most diligent of horse owners will face a bout of colic with their horse at some point. Still, identifying the types of colic and removing as many of these trigger factors as possible, can only help.

Types of colic and symptoms

Gastric distention typically occurs when horses ingest dry or concentrated foods that swell with water intake. Gastric distention is one of the worst forms of colic because left untreated, the stomach can rupture. Unfortunately, once the stomach ruptures, the mortality rate is high. If there is any suspicion of concentrated food intake, call a vet immediately.

Colitis is an inflammation of the intestine with consequences as dire as gastric distention. It also requires immediate veterinary intervention. Another more serious form of colic is when the intestine twists, causing a blockage that requires immediate surgery; unless blood flow to the intestines is restored quickly, the intestines will die.

The more common forms of colic are:

Impaction (intestines blocked by food mass)
Gas colic
Spasmodic colic (increased intestinal contraction)
Unknown cause

These forms of colic typically have a better outlook because they are more easily resolved. Unfortunately, all bouts of colic begin with the same symptoms, even the more severe cases. Calling your vet at the first sign of any of the following behaviors could save your horse's life:

Restlessness, rolling, repeatedly lying down and getting up
Inability or refusal to get up
Biting or kicking at the abdomen or flank
Sweating or lathered
Pawing at the ground
Curled lip
Stretched posture, as if urinating
No water intake
Change in feces or not passing feces
Pale gums and elevated capillary refill time (CRT should be 1-2 seconds)

Learn to monitor the vital signs of your horse

Horse owners might wish to learn how to monitor an equine's vital signs, which can provide valuable additional clues as to the well being of the horse. In a horse at rest, the norms are:

Temperature, 99 - 101 F
Pulse in an adult horse is 30-40 beats per minute; foals (70-120 bpm), yearlings (45-60 bpm) and 2-year-olds (40-50 bpm). Pulse should be regular, not weak and erratic
Respirations, 8-15 breaths per minute. Equal depth of inhalation and exhalation
Capillary refill time or CRT (1-2 seconds)

Purchase a cheap stethoscope for your first aid kit. It can be a crucial tool in an episode of colic. A horse's gut has continuous digestive sounds, if these are absent, something is wrong. Check your horse for dehydration by pinching his skin on the neck. It should immediately return to normal; if it remains pinched looking for more than a second, your horse is dehydrated.

By examining the horse's gums you can look for paleness and capillary refill time. Press the gum area, release and observe, the color should return almost immediately. Anything longer than 1-2 seconds, indicates a circulation problem. The horse's nostrils and eyes can also be observed for paleness. This excellent video from theHorse.com, provides a helpful demonstration on how to take vital signs in a horse.

Prevention is better than cure

There is no guaranteed cure for colic, just potential treatment options that may or may not be successful. The best you can do for your horse is eradicate potential triggers before they happen. This means:

Feeding on a regular schedule, hay and water first, then grain
Supplying ready access to clean, fresh water
Not feeding moldy hay or bad grain
Sticking to a deworming schedule
Introducing diet changes slowly (including limiting time on fresh, lush grass)
Ensuring your horse has sufficient turnout time
Not overgrazing in sandy pastures (sand colic)
After exercise, allowing horses to cool down before eating/drinking
Providing a salt and mineral block. Studies show it reduces the chance of colic

The stabled horse is always at an added risk of colic, particularly when laminitis further restricts turnout time or exercise. These horses will require extra monitoring during rehabilitation.

Frequently asked questions about colic

If I suspect colic, should I call my vet immediately?

Without a thorough examination, it can be difficult to determine the level of severity. If you have a horse that colics more than other horses but has been easily treated, you can walk the horse and see if it helps to resolve the issue. If after 30 minutes, the horse is the same or worse, call a vet immediately. If you have a horse that rarely colics however, don't hold off, call the vet.

Are some horses more predisposed than others, to colic?

The University of Liverpool in the UK, conducted a Colic Epidemiology Study between 2003-06 which provided some interesting and eye opening results. Scientists determined that colic episodes were higher in spring and fall months, which incidentally coincided with changes in habitat and feeding. They also showed that some forms of colic were seasonal, cribbers and wind suckers were 70 times more likely to suffer gut twists, a previous bout of colic in the past 12 months increased the chances of another bout, and taller horses were at more risk.

Ultimately, colic in equines is not something to be messed with. Whenever in doubt, always call your vet, even if only to place him on standby and let him know he may be needed. Remember, you know your horse better than anybody else. If something doesn't appear right with him, or normal for him, then it probably isn't.

Sources (accessed Aug. 08, 2011):