Structure
First of all a little bit more about the digestion of a horse.
It starts with eating food with the mouth. From the mouth the food goes into the esophagus that transfers it further to the stomach through ritmic contractions. The stomach af a horse has a content of only 15 to maximum 20 litres and only one exit. Once the food arrived in the stomach, it cannot go back to the esophagus.
In other words, a horse that can't vomit has a great risk for colic. Because if there's, for whatever reason, a complete intenstinal obstruction, the stomach gets very quickly (within a few hours) engorged. This has sevear colic symptoms as result and the danger of a rupture of the stomach wall. To prevent this from happening we'll first try to empty the stomach of the horse through a tube inserted in the nose.
In the stomach the food gets pre-digested and the bacteries get killed by acids. Out of the stomach the food goes into the small intestine, that can be up to 20 metres long. Here the food gets further digested and the intestinal wall takes some of it in.
Then the more hard digestible food, like plan cells, come into the caecum. With the help of bacterial cultures, plant cells get further broken off so that later nutrients can be taken in by the colon. Also some very important nutrients are being produced by bacteries.
After the caecum, the food goes into the different parts of the colon. First in the big colon that lies in the abdomen like a loop and is about 3 metres long and takes up a large part of the abdomen. Then it goes into the thinner "small" colon that is about 8 metres long. In the colon the taking up of the last nutrients and 90% of the fluids takes place and besides that most of the waste products gets exctreted. The last intestinal part is the rectum, where the food that had changed into manure is being stored until the horse excrutes the manure.
So there are a lot of intestines where something can go wrong resulting in colic. Besides that there are also other organs in the abdomen that can cause colic.
We will only discuss the most common and important reason caused in the intestines.
Symptoms
The symptoms of colic vary strongly with the gravity of the disease. A horse with a light colic, often won't eat, but will look at the belly and kick with its hindlegs at its belly. Sometimes a horse stand stretched and it seems as if it can't urinate. This is often caused because a part of the intestine takes up a lot of space in the pelvis. Herefor the horse will push. We often see this with an obstruction in the colon.
If the colic gets worse the horse will lie down, roll and sometimes sweat a bit. With very sevear colic the horse will sweat very much and it can't stand on its legs anymore. The temperature is often normal (37,2 to 38,2°C) to slightly increased if the horse has been rolling extremely. The respiration is often accelerated and the horse seems to be restless. The heartbeat is often a good meter to see how bad the colic is: the worse the colic, the higher the heartbeat usually is.
Causes
Cramp colic:
Cramp colic is one of the most common causes of colic. With cramp colic the pain begins because smaller or bigger parts of the intestine tenses up, as the name already says. Important cause of this is that the horse ate something wrong and so the digestion is disturbed and matters are being made that make the intestine tense up.
With cramp colic the horse often shows mild colic symptoms with sometimes a watery manure. Besides that you can sometimes hear the 'rumbling' in the belly from a distance.
Cramp colic is one of the least serious forms of colic that often disappears after half an hour walking. If the colic remains after the walk, then you have to warm the vet to see of it's really cramp colic and, if necessar, for a treatement.
Horses that have repeatedly attacks of cramp colic could have a disturbed bacterial culture that is normally present in the intestine. This will be corrected by special food.
Worms:
A second important reason for colic are worms and worm larvae.
Big amounts of larvae creep through the intestinal wall during their development. This can lead to a decreased functioning of the intestine resulting in colic. Especially with young animals you can find a large amount of little worms in the manure that exctreted spontaneously. We see this especially in the winter.
The disadvantageously role that tapeworms can have in a horse seems to be underestimated for years. According to current views they can certainly cause colic.
Besides the necessary meadow measures, regularly worming with a good cure in the right dosis can prevent a lot of problems.
Gas colic:
With gas colic the gravity of pain can differ and is dependable of the amount of gas and the place in the intestines. The pain begins because of the tension on the intestinal wall caused by the gas.
Mostly it is a mild form of colic whereby sometimes the increased abdominal size and frequent farting stand out.
The cause is a decreased agility of the intestine whereby particularly quick digestible components in the nourishment will rice. With this gas will be formed. The decreased agility of the intestines can have many reasons,like stress or even sudden changes in the weather. Hard efforts give also a decreased agility of the intestines, that's why feeding (particularly concentrates) just before riding isn't good.
With a light gas colic it's often enough to walk for half an hour to remove all excess gas. With a sevear colic the vet must be consulted who will examen the patient to find out what the underlying cause is. As a treatement the horse often gets a pain killing injection and an intestinal relaxer. If the horse is in less pain, the agility in the intestines will increase.
In a few cases there is so much gas in the intestines that it won't go out any more in the natural way and is it necessary to puncture the with gas filled intestines. (= let the gas ecape with a large needle). This way the tension on the intestines diminishes quickly, and hopefully increases the agility.
Horses thta have regularly gas colic often have a disturbed digestion. Here as well special food can offer a solution.
Change of location of the intestine:
This is a very grave cause of colic that can sometimes start with mild colic symptomsn but are quickly followed by graver symptoms; Extremely rolling, kicking at the belly, letting itself fall, not wanting to stand up and sweating fit in. It is very important to warn the vet immediately who will establish the cause of the symptoms through a colic examination. In a change of location the intestine can be turned, be stuck in a whole where it doesn't belong (for example an inguinal hernia) or turned in itself.
The chance that such a change of location will heal spontaneously is very small and a surgery is often the only possibility. The succes of such a surgery depends among others of the kind of change of location and the time that has passed between the start and the surgical treatement.
A milder form of a change of location is when a part of the colon has come over the spleen. This change of location often heals after a treatement with medication and movement.
First aid
What does an owner has to do when he or she establishes that a horse has colic symptoms? Keeping the horse moving is desirable. Movement stimulates the intestinal functioning,it distracts the horse and prevents that the horse will get stuck in the stable and harm itself during the rolling. Movement means a little bit of walking, trotting, lunging or riding. Further, a horse with colic symptoms can't eat, so no snacks or anything of that kind! A horse with colic can drink. Controling the heartbeat is very usefull: it often gives an impression of the gravity of the colic. This can happen at the jaw artery: ask us to learn you how to do this during our next visite!
Keep the horse under control and if the symptoms are bad, or don't decrease, it is wise to call the vet.
Finally ...
We hope to have given you with this story of colic notion about this feared condition, that it's clear that not every form of colic is life-threatening, but that caution is desirable.
In doubt, always call!
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