How to deal with Colic in horses

One of the most terrifying words to hear as a horse owner is colic, writes vet Sean Rooney.
Two horses grazing in a buttercup meadow near Sheepwash Bridge. Picture by Jim JonesTwo horses grazing in a buttercup meadow near Sheepwash Bridge. Picture by Jim Jones
Two horses grazing in a buttercup meadow near Sheepwash Bridge. Picture by Jim Jones

Colic is the word given to any form of abdominal pain in the horse.

It has various causes but it is always worth remembering that the vast majority of colics will respond to medical therapy on the yard.

So, what is it?

Mostly colic is related to issues arising from the digestive system; however some are due to urinary or reproductive problems.

What are the signs?

Pawing the ground

Kicking or stamping

Staring at the flank

Lying down

Rolling

Sweating

Curling of neck to hold head in the wrong position

Curling of the upper lip

Stretching as if to pass urine

Dog sitting

Aggression

Depression

Loss of appetite

There are four main types of colic caused by the digestive system:

1 Idiopathic/spasmodic:

This is the most common form of colic and occurs when the gut becomes ‘over-active’. Sometimes we see these occur when feed types are changed too suddenly. So in spring colic is rife, as many of us go from having horses that have been in all winter and out to a diet of fresh grass. The horse over-indulges themselves and the gut bacteria cannot cope. The same applies when changing hard feed choices so do not do it suddenly.

To think about it simply, if the gut is familiar with the feed going through it then a sudden change will cause upset. The use of pre-biotics can help during a feeding transition (on both grass to hay in winter and the reverse in spring). Talk to your vet about which they would recommend.

This type of colic normally responds well to anti-spasmodic and pain relief therapy.

2 Impactions

Essentially a blockage of the intestine, mainly the large intestinal tract. These appear to occur when the horse or the gut material dehydrates. 
Examples of this occurring are:

Autumn to winter transition – the gut is used to grass and then has only hay when the horse is stabled. Hay has a far lower moisture content than grass.

Summer heat – we see a peak in impaction colics during warm weather when the horse doesn’t drink as much as it should.

Winter freeze – water buckets left frozen cause reduced water intake.

Older horses – hay needs to be fully ground down before entering the hindgut. Consider hay replacements when the older horse loses the ability to grind the hay well.

Moved onto a straw bed from a shavings bed and eating the most of it.

As dehydration plays a key role in the formation of impactions, the treatment involves hydration. The severity will dictate how your vet decides best to treat. The most common approach is to pass a nasogastric tube and administer oral fluids. Some vets will use liquid paraffin to encourage softening. I use epsom salts once the dehydration has been resolved, as this encourages the passage as well.

Impactions can also be caused by incorrect or inefficient worming; i.e. when a large worm burden is killed off suddenly and blocks a piece of gut. Or when a large volume of tapeworm gather in one area preventing the passage of gut material. These result in far more severe episodes of colic and may require surgical intervention to correct.

3 Displacements, strangulations and torsions

Put simply a piece of gut ends up somewhere it shouldn’t be. Sometimes this occurs when the gut fills with gas and ‘floats’ into an incorrect position. Strangulations are when the gut’s blood supply is directly shut off. Torsions occur if the gut becomes twisted and cuts off its own blood supply.

A common example of a displacement is nephro-splenic entrapment – there is a ligament that runs between the left kidney and the spleen, a piece of bowel becomes trapped within it and enlarges making the situation worse.

4 Parasite related colic

As mentioned previously parasites can cause impaction colic. But they also pose a risk when they are encysted within blood vessels or the gut wall. Mass emergence can cause dramatic and dangerous colic. To avoid this always speak to your vet as worming should be carried out correctly and appropriately. At the veterinary clinic we strongly advocate worm egg counting and targeted therapy for the most reliable outcome.

Help! My horse has colic!

1 Stay calm

As I said the vast majority of colic will respond to medicines on the yard.

2 Call your vet

Colic is a true emergency and a vet is required as quickly as possible to prevent it worsening.

3 Move your horse to a well-lit area, allowing for observation and examination when the vet arrives.

4 Remove all food from your horse, even if they do still want to eat.

5 If your horse is rolling, keep them walking gently, only if it is safe for you to do so. Violently colicing horses can cause themselves injuries or get cast whilst rolling. Keeping them distracted by walking until they can be assessed is helpful thing. Again, only do so if it is safe; your horse will not recognise you whilst they are in distress. Endangering yourself will not help your best friend.

6 Think of any pertinent information for your vet when they arrive. Such as:

Any previous episodes of colic

Age of your horse

When did the colic episode begin

Has anything changed in your horses husbandry? ie new pasture, stabled for first time in months, new feed materials given.

Have they passed any faeces?

When were they last observed eating and drinking

Recently foaled? Pregnant?

Worming history?

7 Have the kettle on

Not just because I like a coffee, but a supply of hot water is always appreciated by your vet, especially if your horse requires stomach tubing of fluids.

8 Think what you would like to do should the vet advise a referral

It is always a relief to a vet to know that your horse is insured; that way serious events like this do not have significant financial implications associated. We can work to the standard at which we are trained to do so without making adjustments for a lack of finance.

What will the vet do?

The colic examination allows the vet to diagnose the cause of the colic.

The main parts of the examination are:

1 Taking of parameters. Heart rate, respiratory rate, capillary refill time and temperature. Resting heart rate should be 30-40 beats per minute for a normal horse.

2 Gut sounds. Your vet will assess the gut in four quadrants by listening for gut motility, be that increased or decreased, normal or absent.

3 Rectal examination. Please hold your horse securely for the vet to carry out this procedure. They are really at risk doing this and incompetence in holding the horse could result in serious injury. This is often carried out over a stable door and with sedation. This gives the vet the ability to assess the rear third of the abdomen, their arms can only reach so far.

Adjuncts to the main exam are:

4 Passing of a stomach tube. Your vet is looking for reflux, this occurs when there is a blockage of the small bowel and fluid builds up in front of it. Horses cannot vomit so this is the only way to release this. Presence of gastric reflux is a strong indicator of the requirement for surgery.

5 Abdominocentesis. A fancy term for a belly tap, the lowest point of the belly is clipped and cleaned, then a needle is placed and any fluid obtained is examined to indicate gut health.

What then?

As I have stressed throughout this article colic is generally easily treated. Most of the time your vet will administer drugs and perhaps fluids. They will advise you to starve your horse overnight and may return to check on them or ask you to keep them posted.

There are times when referral for a further workup or surgery is required. Your vet may administer certain drugs to keep your horse comfortable and will arrange referral to an equine hospital. Your vet will help you to weigh up all the key considerations such as the severity of the issue and the prognosis for your horse, the likely expenses and how to act in the best interests of your beloved.

Key points:

1 Avoid rapid and sudden diet and management changes

2 Practice good preventative health programmes such as strategic and targeted worming

3 Know that even the best managed horse can still colic without reason

4 Keep calm and call the vet.

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