There have been a large number of horses with colic in the clinic recently. The term colic refers to any cause of abdominal pain from the gastrointestinal tract and so can have very many different causes.
Signs of colic vary according to the seriousness of the cause and the disposition of the horse. Some stoical equines (most notably donkeys) can have severe colic and yet display very few clinical signs of pain.
Signs of mild abdominal discomfort
- lifting the upper lip,
- flank watching,
- lethargy,
- lying down more than normal,
- pawing the ground,
- restlessness,
- poor appetite,
- not passing droppings or passing less droppings than normal,
- changes in the consistency of the droppings.
Moderate to severe discomfort
- as above plus,
- kicking at the belly,
- kicking out,
- rolling,
- sweating,
- groaning
How Common is Colic?
A study in the USA found that the incidence of colic within the general horse population was 4.2 colic episodes per 100 horses per year. The number of horses that die because of colic are reported as 6.7% to 15.6%. These statistics highlight the importance of preventing colic.
Survival rates are increased when there is early veterinary attention and treatment so call your vet as soon as you see your horse colicking. Most colic cases will respond to medical therapy, but a small number of colics require surgery. These surgical types of colic can progress extremely rapidly, and early intervention is paramount in ensuring a successful outcome. This is particularly important in old horses (>16 years old) as a particular type of colic called strangulating lipoma can occur where a fatty lump on a long stalk can wrap around parts of the small intestine and cut off the blood supply.
In many cases of mild colic, the exact cause may remain unknown, however studies have identified several risk factors.
Risk Factors
- Increased incidence in all types of colic occur during October/November and March/April. This may be due to fluctuations in temperature and grass growth and changes in management practices such as turnout, stabling and exercise which commonly occur at these times of year.
- Impactions (dry ingesta which builds up in the colon causing a blockage) are most common in winter. Risk factors for impaction colic include sudden increase in the number of hours stabled, decrease in exercise, lack of access to pasture, feeding more coarse roughage, decreased water intake, and dental disease.
- A recent German study showed an increase in colic in horses which had been wormed the week prior to presentation at an equine hospital. However, high worm burdens are also associated with colic and therefore rather than avoiding worming, it is important to support the hind gut microbiome when worming.
- Epiploic foramen entrapment is a serious form of colic with a high fatality rate that requires surgery to correct it. The epiploic foramen is a natural gap by the liver where small intestine can occasionally get trapped and the blood supply cut off. Epiploic foramen entrapment is most common in the winter months although the reasons for this are not clear.
Management factors:
- Sudden changes in diet
- A high concentrate diet
- Restricted access to water or reduced intake
- Poor worm control
- A change in management
- Limited or no time at pasture
- Reduced exercise
- Poor dental care
Tips for preventing winter colic
- Daily turnout, at least for a few hours. This could include in a school or menage with hay nets if no grass is available.
- Gradual changes in the amount of exercise and feed.
- Feed according to amount of exercise.
- Regular dental checks and rasping.
- A regular deworming programme based on faecal egg counts.
- If your horse is prone to eating its bedding, using an inedible bedding such as shavings is advisable rather than straw.
- Adequate hay or haylage provision aids gut function as well as alleviating boredom.
- Add probiotics to the feed at times of management (e.g. worming) or feed changes. Ensure the supplement contains a live probiotic that is protected from stomach acid so it reaches the hindgut.
- Monitor the number of droppings your horse produces so you know what is normal.
- Monitor your horse’s water intake; reduced water intake is a risk factor for all colics, especially impaction colic. In winter your horse may be encouraged to drink by adding some warm water to the water bucket to take the chill off it or adding apple juice to water. Some horses can be put off drinking if their water is very cold. Make sure that field and stable water buckets and troughs do not get iced up and be careful with automatic drinkers in stables as it is impossible to monitor how much your horse is drinking and they can get iced up or dirty very easily which can put your horse off drinking. Soaking hay and wetting feed are other ways of increasing your horse’s water intake.
