Colic

Colic – simply means your horse has belly ache: so why do we worry so much? Well, nine times out of ten it will luckily resolve simply; just a case of bellyache similar to us after having 3 portions of Christmas pudding, when we should only have had two.

However, in some cases it can be serious and life threatening and the initial signs may not allow you to differentiate the two!

There are a number of reasons why horses suffer more commonly from colic than other species. They are termed hindgut fermenters, which means that after food passes through a stomach and small intestine similar to ours, the fibrous part of their diet (grass and hay) is then digested in the large colon. This is a large V shaped structure where fermentation takes place. This colon contains huge numbers of bacteria and when full of grass can weigh over 100kg (in a 500kg horse). The colon is held in place inside the abdomen (belly) by sheets of tissue called mesentery. Unfortunately, these sheets are long in horses and allow the colon to move around a lot. The combination of a movable large colon and a structure that can rapidly fill with gas (from the bacterial fermentation inside) means it is prone to being shifted out of place, and that is definitely painful! The second problem is that horses are unable to vomit. This is due to a number of anatomical reasons but means that if fluid builds up in the stomach (which would cause us, dogs, cats and just about any other species to vomit), in horses it leads to stretching of the stomach, which again is very painful, and can cause very marked colic signs.

What things cause colic?
These are literally hundreds of causes of colic and often we do not determine the exact cause of your horse’s pain and discomfort. That said, in general the different causes tend to fall into four categories:

1. Spasmodic colic: this is when the gut becomes too active and starts to spasm and contract too fast
2. Impactions: this is where food material forms a solid mass within the intestine. It most commonly occurs in the large colon
3. Displacements: this is where a piece of gut moves out of place and becomes trapped somewhere within the abdomen it shouldn’t be
4. Torsions: this is where a piece of intestine twists around itself or some other structure within the abdomen. These colics are often very serious because the intestine’s blood supply is cut off and the intestine will start to die if surgery is not undergone quickly to correct the twist.

What are the clinical signs of colic?
These will be quite variable depending on the severity of pain. In mild cases colic may cause loss of appetite, flank watching and pawing of the ground. In more severe cases this will progress to active rolling and this may continue despite distraction or any attempts to keep the horse on its feet.

Toxic Gums

What should I do if I think my horse has colic?
As a general rule, a vet should see all horses with colic. Whilst waiting for them to arrive, remove all feed from the stable although water is ok, and if the horse is rolling try and remove any sharp objects that they may injury themselves on.

We are often asked whether horses with colic should be walked. In many situations this can be helpful. Certainly if the colic signs are mild then walking may help relieve gut spasm and some gas. However, if the horse is wanting to continually lie down and roll then he/she is best left in the stable where there is less change of injury to the horse and any people dealing with him/her. Rolling almost always will not make the colic worse.

What will the vet do?
This will depend on the cause of colic. Our initial examination will include taking a heart rate, looking at gum colour, and listening to the gut sound produced by the intestine. It is also very common to do an internal (rectal exam). This helps us to tell if gut is distended and stretched, impacted or out of place. In some cases we also pass a tube down the horse nose into its stomach, to allow any fluid collecting in the horses stomach to be removed. Treatment will depend on the cause. In situations where the colic appears to require surgery (e.g. a twisted gut) then the horse will be given pain killers and immediately transported to a centre with surgical facilities. If the colic appears to be spasmodic then we will often administer gut relaxants. In cases of impactions then lubricants such as liquid paraffin and electrolyte containing fluids may often be administered by a tube passed down the nose to the stomach. In some cases painkillers and a period of no food may be all that is required.

Nearly all horses are starved after a bout of colic, usually for 12 hours although this may be considerably longer if a large impaction is present. Food is usually re-introduced slowly: the horse being watched carefully for further signs of colic during refeeding.

How can I prevent colic?
Unfortunately there are no ways of entirely preventing colic. Many cases such as a twisted gut just occur by chance, and no prevention is possible. However the following may minimize other types of colic:-

1. Ensure your horse’s teeth are in good order so he/she can adequately chew their food.
2. Ensure your horse is wormed regularly. Many intestinal parasites are associated with colic.
3. Do not make sudden changes to your horse’s diet if they can be avoided. Bacteria in the colon take a while to adapt to changes in incoming feed