What a winter we've had so far, with major weather events hampering our horse’s usual routines and reduced turnout and exercise in general being the most likely impact.

Changes in routine can wreak havoc on our horse’s digestive system with colic being the number one issue. The main problem with colic is that, in the early stages, it is impossible to distinguish a mild attack from a potentially fatal one and therefore all cases of colic should be taken seriously.

There are steps that we can all take to try to minimise the risk of colic in the equine population.

Risk factors:

Unfortunately, if your horse has had colic before, they are at a high risk of a recurrence. In a study looking at colic and possible causes, 43% of horses with colic had previously experienced a colic attack.

It is also thought that 50% of colic cases are related to diet management. They are also at a higher risk if fed a high proportion of grain (fit, hard working horses) or are on restricted turn-out.

Winter causes:

There are a few factors which contribute heavily to the increased incidence of colic during the winter:

1. Horses drink less water, either because they are not as thirsty or because their water supply has frozen up (in the field or stable). Hay and haylage is only approximately 10-40% moisture compared to the 75% moisture contained in spring and summer grass.

With this decrease in moisture intake the processed feed is too dry to move along the digestive tract and problems with impaction can occur. This problem usually builds up over a period of weeks and there may be early warning signs; less or very dry droppings or reduced water intake.

2. When the colder weather comes the inclination may be to increase the hard feed portion of the ration, ie more grain. This is likely to upset the digestive processes.

3. Decreased turn-out time, or no turn out. Inactivity may slow the movement of food through the digestive tract. Suddenly being stabled for longer than usual due to massive weather events will reduce activity.

4. Sudden changes to exercise or feeding routines can also cause digestive upset.

All or some of these factors can be the trigger for a colic attack during the winter months, so what can we do to limit the risk?

Read more: Clyde Vet's equine advice: Coping with sand colic in horses


The causes of colic are multi-factorial and there is no single thing that can be done to prevent it, but there are things we can do to limit the risk.

1. Water – Make sure that water is fresh and not frozen all day, also check that the footing to the water trough is OK. Some horses will not drink really cold water so offer them a bucket of water that has been warmed.

This is easily done with a kettle, or Thermos of boiled water added to a bucket. This trick will also lower the chance of water buckets in stables from freezing. Feed salt to encourage water intake.

2. Include water in the feed whether in the form of a mash, sloppy sugar-beet or just adding plenty of water to a chop-based feed. Offer extra sloppy sugar-beet as a means to encourage horses to drink, especially good if it can be made with warmer water.

3. Routine – make sure that you have a feeding routine and stick to it as much as practically possible. Make any changes gradually. Especially be aware of swapping from hay to haylage (and vice versa) and make sure that this is done very slowly and with great care.

As far as the bugs in the horse’s gut are concerned there is a very big difference between hay and haylage and many an upset stomach has been caused by a rapid swap.

4. Roughage – feed mainly fibre (hay, chaff, sugar-beet etc), only feed cereals if absolutely necessary and try to use high oil products (or oil itself) as an energy source as much as possible.

5. Feed little and often – try to spread your horse’s daily ration over as many feeds as practically possible. This is particularly important if they need a lot of hard feed.

Remember, the horse’s stomach is only the size of a rugby ball and no more than 2kg of concentrate should be fed per meal (preferably less).

6. Worming – make sure you have an effective program in place. Especially make sure that your horse is wormed against small encysted red worms in December/January.

Unfortunately, these do not show up in worm egg counts so should be part of a strategic/targeted worming schedule. Dung samples can be sent off for worm egg counts to check if your horse’s need a routine wormer.

Speak to your vet or local animal health shop SQP (suitably qualified person) about a good worming regime. Pick up droppings from the field (our winter weather is not really cold enough to kill off worms).

There are many other causes of colic that we do not fully understand but if attention is paid to the above areas then the risk of a colic episode should be greatly reduced.