Understanding Colic

Colic simply means abdominal or belly pain. Most horses will have an episode of colic at some time during their life, but as some owners know, a horse rolling and thrashing violently on the ground can be quite a scary sight.

Symptoms of Colic

As horse owners, it is extremely important that you can recognise the symptoms of colic so as to enable early veterinary intervention. A horse with colic is a sick horse, and most horses with colic do not want to eat.  In some early cases of colic this symptom of not eating up their feed may be the very first indication that something is wrong.  In mild cases of colic a horse will show pain by just turning and repeated look at its belly.  Perhaps they may sweat a little, or curl their upper lip.  Some horses will dog sit like this horse on the slide.  As the pain worsens, they may paw at the ground with a front leg.  If the pain gets worse, your horse may roll about on its back, sometimes violently, taking skin off from around their face.  A horse with colic may distend in the belly, appearing swollen and bloated, and they may or may not pass manure.

If your horse shows signs of colic you should call your veterinarian immediately.  Most cases require urgent veterinary intervention.  While waiting for the vet there are a couple of things that you should remember.  Do not feed your horse, and if the horse is pawing and trying to roll walk them briskly to prevent them going down.  There is a risk that rolling on the ground may result in a twisted bowel.

Be careful when dealing with a violently rolling or thrashing horse.  Do not put yourself at risk.  If the horse can’t safely be kept on its feet, just leave it down until the veterinarian arrives.

Causes of Colic

The causes of colic are varied.  Most are the result of gas build up in the gut which causes distension and stretching of the gut wall.  This causes the pain that we associate with colic.  Other colics are due to excessive spasm of the gut, while some are the result of blockages.  Blockages can be caused by feed such as hay or foreign bodies like string or plastic bags as well as enteroliths, which are large stones that from over time in the horses gut.  These enteroliths are a common cause of surgical colics in this area.  The form in the horses gut, starting as a little tiny stone, minerals from the diet concentrically coat them and they get bigger, and as they roll around in the gut they develop into these smooth balls. E ventually when they are big they move into a bottle neck within the gut and obstruct it.  They can get to be the size of a small football.  Even a large worm burden can cause an obstruction.

Sand accumulation can also cause colic.  Sand and dirt is ingested in horses that are fed from the ground in sandy or loamy country.  Small amounts of sand in the gut will mechanically damage the inner gut lining resulting in inflammation and pain, occasionally large amount of sand can accumulate in the gut over months or years and this obstruct the gut.

As much as 20 litres of sand has been reported blocking the gut.  Very rarely the horses gut can spontaneously twist.  This can be the result of a gassy distended gut becoming buoyant and twisting around on itself, or a twist could result from a horse rolling about with colic pain.  This is a real emergency and if the twists aren’t corrected quickly the gut dies. This is fatal for the horse.

Let’s look at some examples of gut that twists , or moves into the wrong place.  This first example is of a horses large intestine that twists around on itself.  This is a real emergency, for this horse to be saved it must get onto the operating table quickly.  When gut twists like this the blood supply is cut off to the twisted portion of bowel.  This has to be corrected before the  bowel dies from lack of blood supply.  This next example is of some small intestine that accidentally moves through a tear in this sheet of aft within the abdomen.  You can see the gut moving through and now it is locked off with it is blood supply also affected.  If this gut is too sick at surgery to leave then it can be cut out and the gut rejoined.  This final example is a displaced large bowel.  This gut has just moved in to the wrong place but is not twisted off.  This is also a surgical colic but these can go for some days before being operated on.

Diagnosis of Colic

As a veterinarian assessing a horse with colic, it is our job to determine if your horse has a medical colic or a surgical colic.  A medical colic is one that will resolve with injections and stomach drenches, while a surgical colic is just like it sounds.  That is, a colic that requires emergency surgery.  To determine this we consider the level of pain, how long the colic has been going on for, the response to pain relieving drugs, heart rate, gum colour and any changes in these, as well as the amount and quality of gut sounds we can hear with a stethoscope.  Occasionally we will place a stomach tube, or we may do an internal examination, a belly tap or an ultrasound.  These procedures help us to work out how severe the colic is, what is likely to be causing it and then how to best treat your horse.

Treatment of Colic

The vast majority of colic cases respond to treatment in the field.  That is, at your property or agistment centre.  Injectable medications such as pain killers and sedatives to stop or prevent rolling are usually administered.  Sometimes other treatments such as electrolytes or paraffin oil are given via stomach tube.

While most colics respond to simple treatments such as these and get better, occasionally a horse with colic will need more intensive medical treatment.  These horses present with significant life threatening blockages or impactions of the gut, or just fail to respond to treatment in the field. T hese horses are admitted to our hospital where we can treat and monitor a horse more intensively.  In most cases the horse is put on a drip and very large volumes of fluids are given.  Most horses have at least 20 litres and some have 100 litres or even more.  Medications are often repeatedly given via stomach tube and the patients are examined frequently.

In many serious colics, the horses condition improves following this intensive treatment, but for those that don’t improve or for those whose colic is even more severe, surgical intervention is necessary.  Fortunately these cases are few and far between.

Surgical cases are those with twisted gut or blockages that don’t respond to medical treatment.  These horses are put on the operating table and the abdomen is opened and explored in order for the surgeon to correct the problem.

Don’t let all this scare you though.  The good news is that most cases of colic don’t require intensive or invasive veterinary treatment, with most getting better following simple treatment at home.

Prevention of Colic

Plenty of cases of colic develop despite the horse receiving the best care.  There is no doubt though that certain simple management strategies will lower the chances of your horse developing colic.

Ensure you feed your horse enough fibre in its diet.  A minimum of 1% of your horses body weight is required.  Another way of looking at this is to say that half your horses daily intake of food by weight should be fibre.  You have to be careful not to feed too much grain and ensure a constant supply of clean water.

Horses are creatures of habit so try to keep your routine the same.  Feed at the same time morning and evening and avoid sudden changes to your horses diet.  In situations where no pasture is available for grazing, small feeds frequently are best.  Don’t feed off the ground in sandy or dirty conditions as your horse will inadvertently pick up some of this sand as they eat.

Regular annual or biannual dental treatment is essential to prevent feed impactions from unchewed food and regular worming every 6 to 8 weeks is another must.  Worms and bad teeth can cause life threatening colics.