Colic in the horse is unfortunately a common health condition and is one of the top reasons for euthanasia in veterinary practice. There are many unknowns when it comes to colic conditions, and with it, many different types of colic conditions. Many types have a good prognosis while others are not so favorable. What more do we know about colic? What more can be done to potentially prevent these conditions and what can you, as a horse owner do to monitor your horses?
Colic. A word that just with the mentioning of it can raise the heart rate and blood pressure of any horse owner and likely, their veterinarian. It is a potentially serious condition in any equine patient, and no matter how many times you contend with it as a veterinarian, the situation never gets easier. There are so many unknowns that it can create dilemmas regarding how to manage and more importantly, how to prevent in the first place.
Colic in the Horse. What is it?
Colic simply implies abdominal pain or discomfort. The condition of colic is most often associated with the gastrointestinal tract, but the pain can be created by other organ systems from the liver or kidney, to the reproductive tract or bladder. Simply put, in a case of colic the horse has abdominal pain. The source of that pain can vary from one case to the next, but most are associated with intestinal pain or discomfort.
When looking at the intestinal tract, pain is often created in the horse when there is distension of a piece of bowel. To make this more visual, if you take a balloon and begin to inflate it, it distends or increases in size. This distension, when it comes to the GI tract, creates pain. The distension can be due to excess gas production, a blockage of some form, or due to an abnormal position of that section of the intestinal tract. When we have pain in a horse with colic, there is distension, and now the question is what is the cause of that distension.
Most common causes of colic in the horse include:
- Gas or flatulent colic
- Small intestinal obstruction/impaction
- Large intestinal obstruction/impaction
- Displacement of the large colon
- Colitis or Enteritis
- Gastric ulcers
With the exception of the last two causes, most do cause or create distension which then creates pain. The conditions of colitis, enteritis, and gastric ulcers have an inflammatory component associated with them, and thus irritation on some level which creates the discomfort.
Clinical Signs of Colic in the Horse
Colic implies abdominal pain or discomfort in the horse. With that being said, dependent on the severity of the condition, the pain level can vary tremendously. This pain level can also be an indicator of the severity of the condition and used as a monitoring tool.
Typical signs of colic in the horse include:
- Off feed
- Restless, pawing, circling or weaving
- Looking at flanks continuously
- Lying down with rolling
- Excess gas production
- Depressed or anxious attitude
More often than not, these clinical signs are present together, rather than just one being present. For example, you may have a horse that is refusing that night’s feed, but is also restless and pawing. Just because you see one or two of these clinical signs, it is not a time to panic, but more so a time to step back and evaluate the situation. This is where performing a quick physical exam can come in handy for you as the horse owner.
Assessing the body temperature, gum color, capillary refill time, respiratory rate and gut sounds is very helpful and can help you to get a better handle on the situation.
The Vital Signs in the Equine Colic Patient and What They Mean
When evaluating any horse with colic, you as the horse owner must take precautions for safety. These horses can be very painful and often unpredictable regarding their behavior. Some are very stoic and just stand there, allowing you to get a physical exam done, while other will violently throw themselves to the ground in pain. Take precautions! If your horse is that painful, the best thing to do is to contact your veterinarian for further advice and to obtain an examination.
If you elect to perform a basic physical examination, and all is safe to do so, these are the points to keep in mind.
The first thing to evaluate is your horse’s body temperature, being careful with the thermometer especially if your horse is restless. Are they running a fever? If so, this could be an indication of pain/stress or an infectious cause associated with the colic.
The second thing is to evaluate their attitude. Are they stress and anxious, or are they more depressed with head hung low? A more stressed and anxious demeanor may coincide with high levels of pain or discomfort. A depressed attitude may connect back with a fever or deteriorating health condition.
The third thing is the heart rate. How high is the rate? Considering that 35-40 bpm is normal, how high is your guy? The level of pain in your horse is often reflective in the heart rate. The good news is that the less severe conditions often have the lower heart rates, even though they are still higher than normal. Cases of gas colic, as an example, can appear quite painful, but yet, their heart rates are often only around 48 bpm. Cases of large colon displacements are generally pretty stoic unless there is compromise, with heart rates from 48-80 bpm. As conditions deteriorate or you get into more serious colic causes, the heart rates can easily climb above 80 bpm, especially if there is dehydration and impending endotoxemia.
The fourth thing is the respiratory rate, which again can help us to determine pain levels in the horse. The respiratory rate often mirrors the heart rate, climbing in the patient, as pain levels rise. It is not uncommon to have respiratory rates around 20 bpm or higher, comparing that to a normal of 12-15 breath sounds per minute.
The fifth thing is gut sounds or gastrointestinal sounds. These can be performed using a stethoscope against the abdomen in 4 different quadrants, listening for evident gurgling or other noises. It is noteworthy if you fail to hear any sounds at all, which could indicate that the section of bowel is not moving properly, termed ileus. While you are assessing gut sounds, take a good visual look at your horse from behind. Is the belly distended or swollen? If so, where? Gas colic cases tend to have increased gas sounds, while more obstructive types of cases often have reduced or absent sounds in various quadrants.
The sixth thing is to evaluate the gum color and capillary refill time. Lift your horse’s lips and take a close look. What color are his gums? A normal horse is a salmon pink, moist with a refill time of less than 3 seconds when you press a finger and release. A horse with a white or light pink color may indicate anemia, dehydration, or shock state. A horse with a dark red color and delayed refill time may also indicate dehydration, but commonly is associated with endotoxemia and severe colic. A horse with a purple gum color is generally a poor prognostic sign and indicates very poor circulation due to various reasons.
Now that you have evaluated your horse with evident colic signs…what do you do next?
We will cover this in another article.
Author: Tom Schell, D.V.M., CVCH, CHN