Colic. . . one of the most dreaded conditions by the average horse owner. It equates to pain for your companion, potentially long nights of monitoring and even costly veterinary care in the worst scenarios. The good news is that in the majority of colic cases, the problem often resolves on its own over a short period of time with some TLC and dietary changes. There are many different types of colic, which essentially means abdominal pain, but that belly pain can be coming from anywhere.
Horses tend to have very sensitive gastrointestinal tracts that are susceptible to upset due to stress, dietary changes, parasites, various medications and even changes in barometric pressures. As a veterinarian, I would often keep tract of incoming weather fronts and would be able to pinpoint which clients I would be hearing from that day or evening. Barometric pressure plays a major role in the development and movement of gas within the lumen of the horse’s bowels and can be quite dramatic at times.
The most common type of colic seen in my practice is what is termed a gas colic, which may be associated with changes in feed, stress, pasture changes or even barometric pressures. Some feeds are more likely to lead to gas formation, which is especially prevalent in the spring with lush pastures. The bowels always contain gas at any given time, which exerts a specific pressure outwards on the bowel lining. When the gas is excessive, the pressure is increased against the lining and pain is perceived as it stretches. Barometric pressure often changes, which induces changes in the gas pressure as well.
The second most common type of colic, at least in my practice, is that associated with stomach or gastric ulcers. These horses generally have a history of gastric ulcers, which are flared up due to changes in feed or excessive stress levels. In these cases, we can have a wide range of pain levels as well as dehydration, dependent on the severity of the ulcer.
Other less common types of colic include impactions or blockages of the stomach, small intestine or large colon. These conditions are often associated with low water intakes as well as consuming foreign material or feedstuff that is hard to digest. Large colon impactions are common to certain breeds, but are most often seen when water is limited or is frozen or cold during the winter months. Displacements or twisting of the bowel is yet another source of colic in the horse, but involves a much lower percentage of horses. Colic pain can becoming from anywhere in the abdominal cavity, thus in mares sometimes we will have reproductive or genital concerns. In other cases, we may have a primary problem such as diarrhea (colitis or enteritis) or even laminitis, which then create secondary symptoms of colic.
Most horse owners are quite astute and know how to recognize if their horse is colicky. Typical signs include rolling, sweating, pawing with heavy breathing at times. Pain levels can range quite a bit, dependent on the severity of the condition and it is not uncommon to have some horses with severe impactions just seem “off” to the owner for a day or two with no evident rolling. In most situations, the clinical signs come on rather quickly and there is no notation of the horse being off his/her feed, but often they seemed just fine even an hour ago, but are now rolling and uncomfortable.
The veterinarian will usually evaluate the heart and respiratory rate initially to help gauge the severity of the condition. The heart rate tends to climb or increase with pain and the amount of increase can be used by the veterinarian to gauge the severity of the colic and rule in/out causes. The next step is usually to listen to the abdomen to determine the presence of ‘gut sounds’, which is movement of gas and feedstuff as the bowels contract. Generally, the presence of consistent GI sounds is a positive thing, however, one can also determine if there is excessive gas accumulation, which may prove to be troubling. The gums or mucous membranes will also be evaluated, which help to determine hydration, perfusion as well as the presence of possible toxemia. Body temperature is also important to determine as an elevation in that number can not only equate to stress, but potentially also indicate an infectious cause such as enteritis or colitis.
After the basic examination is performed, the veterinarian may then chose to perform a rectal examination in order to determine whether if the bowels are in their proper locations and if there is any palpable abnormalities such as a displacement or impaction. This often times requires sedation to perform safely and to minimize stress to the horse. A nasogastric tube may also be placed to determine the presence of gas or fluid accumulation within the stomach, which may indicate a stomach or small intestinal obstruction.
In cases of upper GI problems, such as suspected ulcers, the veterinarian will often rely on an endoscopic examination, in which the stomach can be visualized and inspected, if this modality is available. Other tests available include an abdominal ultrasound and if fluid is present, an abdominocentesis, in which fluid is recovered for laboratory analysis.
The severity of the condition determines the type of treatment offered. In simple cases of gas accumulation, treatment would include a pain injection as well as possible mineral oil infused through the nasogastric tube to help move the gas onward. Handwalking is often very useful as it helps to stimulate the gas to move and spread out within the bowel. Colics associated with more severe gastric ulcers can be a little more tricky to manage and involve the use of antacids or acid blockers in addition to pain medications. In more complicated cases, such as with obstructions, other therapies include IV fluids to help rehydrate the horse and move the impaction. In cases of displacements or torsions, surgery is unfortunately the only option as medical therapies have not been rewarding.
Colic prevention is the key, but can be tricky as one never knows what can trigger an episode. There is very little we can do about the barometric pressure, but we can monitor the diet closely to reduce feeds that may produce excessive gas. Excessive grain intake as well as the use of some pelleted types of feeds are associated with higher levels of gas, stomach ulcers as well as impactions. The most common cause of impactions in my practice was the improper use of beet pulp. Certain hays have also been associated with in an increase in colic due to low roughage type content. Bermuda hay is one of several and the current thinking is that the hay quality is so fine, that it may not stimulate proper GI motility or movement.
Gastric ulcers are a very common condition not only associated with colic, but also behavioral and training problems. Therapy often includes antacid type of medication as well as acid blockers, which can have not only long term health implications, but can also be very expensive. Ulcers and GI upset are often a part of life for the competition horse, and prevention is the key to keeping these problems under control. In our experience, we gain the best results by utilizing ‘soothing’ type of herbs, including Marshmallow and Aloe in high levels (Cur-OST EQ Stomach), as a part of the normal daily diet. These herbs have been demonstrated in human studies to help repair the stomach mucosal lining and soothe the ulcers, and thus reduce the discomfort, making the patient more responsive and at ease.
Monitoring and maintaining dental health is also key, especially in the older horse. If the feed is not chewed properly, then the incidence of impactions and stomach upset increase dramatically. Routine deworming is also important in order to minimize parasite loads that can contribute to colic cases.
Gastrointestinal health is a major player in colic prevention and an area that I believe many herbs can prove beneficial. This is an area we are exploring not only for potential colic prevention, but for those horses prone to gastric ulcers as well. If this is something you’d like to discuss further, please feel to reach out to me.
All my best,
Tom Schell, D.V.M.
Nouvelle Research, Inc.