What is colic anyway?

Externship Project

Hi everyone, this week I would like to talk about equine colic. If you have been around horses or know a person that owns a horse, I’m sure you have heard the word colic before. So, what is colic really? In the simplest terms, colic refers to abdominal pain. Horses show abdominal pain through a wide variety of clinical signs. These range from mild signs (looking/ biting at their abdomen, yawning, stretching out their neck repeatedly, and sweating), to moderate signs (biting/ kicking at their abdomen, pawing the ground repeatedly, laying down, frequent posturing to urinate and muscle tremors), or severe signs (rolling, violently throwing themselves to the ground, distended abdomen and panting). Horses that are experiencing colic symptoms generally have an elevated heart rate, respiratory rate, and change in the mucous membrane color. There is a wide variety of reasons that a horse becomes “colicky”, lets discuss a few common reasons:

Tympanic Colic: 
Tympanic colic is due to bloating from gas within a portion of the intestinal tract. This gas distension triggers pain receptors as the intestine is stretched. This can occur after consuming highly fermented feeds, errors in feeding, and behavioral vices such as cribbing (a horse that is cribbing will place his incisors on a hard object and suck in a large amount of air).

Impaction colic:
Impaction colic is a physical blockage within the horse’s gastrointestinal tract. This can happen due to dehydration, ingestion of foreign non-digestible material, mass die-off of a large burden of parasites, and poor dental health. This physical blockage causes the intestine to get distended, causing pain.

Spasmodic Colic:
Spasmodic colic occurs when a horse experiences rapid changes in weather or diet, has poor dental health, parasites, as well as other unknown causes. You may be asking; how does this relate to intestinal pain? In the simplest terms these things cause irritation. This irritation causes the intestine to spasm and become distended and painful.  This condition generally causes intermittent, acute (rapid onset), moderate-to-severe signs of colic.

Entrapment:
Entrapment happens when a portion of the intestinal tract travels out of its normal position and becomes trapped within an area of the abdomen. The most common entrapment is nephrosplenic entrapment. This happens when a portion of the horse’s colon becomes bloated with gas, allowing it to rise. It then can then lay in-between the left kidney and the base of the spleen. This leads to the colon becoming distended with gas, causing pain.

Torsion, Volvulus, or Strangulation:
Torsion and volvulus both refer to twisting of the intestinal tract. These conditions can happen secondarily to gas colic. Strangulation occurs when a piece of intestine becomes “tied off”, such as when fat tumors in the abdomen get caught around a piece of the intestine.  These conditions essentially strangle the intestinal tract, cutting off the blood supply to a portion of the intestine. This causes distension cranial (towards the head) to the torsion/ volvulus, and lack of blood flow to the affected portion of the intestinal tract, causing pain.

False colic:
False colic happens when horses experience pain that does not actually originate in the intestine. These horses will display signs similar to those experiencing colic. Common causes of false colic are: advanced pregnancy, testicular torsion, hemorrhage, severe respiratory conditions, diarrhea, laminitis (inflammation of the connection between the hoof wall and your horse’s hoof bone), and muscle inflammation. 

What should you do if you think your horse is colicking? 
If you notice your horse has any of these clinical signs, the first step is to contact your veterinarian. The second step should be to avoid injury to yourself and your horse. Walking your horse can help prevent your horse from injuring itself. Horses often lay down, roll or thrash, causing self-harm. Be cautious, a painful horse can abruptly lay down and roll/thrash not realizing that you are in the way. Next, remove all feed and do not administer any treatments unless directed by your veterinarian. 

While waiting for your veterinarian to arrive, record any clinical signs you see. Include the time and frequency that the clinical signs happen. Once your veterinarian arrives, they will gather your horse’s vital signs.  These vital signs and the history of clinical signs you provide will help determine the severity of your horse’s condition. They may need to do additional diagnostics, such as rectal palpation and passing a stomach tube, before making recommendations about how to manage the colic. If you have helpers, setting up a bucket of warm water (6-8L) to have on hand for their arrival is one way that you can get prepared. However, this should not come at the expense of yours and your horse’s safety as your number one concern while you wait for them to arrive.