Colic in Horses

What is Colic in Horses?

There is nothing that strikes fear into the heart of every horse owner more than an episode of colic. An umbrella term for abdominal discomfort, there are many different types of colic in horses. What type of colic your horse has and what caused it in the first instance are often tricky to get to the bottom of. Our guide will walk you through the causes of colic in horses and how to manage the risks with diet control and how to react when you think your horse is suffering from colic.

What Causes Colic in Horses?

Nutrition is just one colic risk factor and specific nutritional risks that are frequently reported, but not exclusively the cause, include limited grazing time, feeding cereal based concentrates and dietary change.

Colic & Limited Grazing Time

Hudson et al., (2001) reported that stabled horses or those that had a recent grazing reduction were 3 times more likely to have colic as those at pasture 24/7. Why might this be the case? What’s protective about pasture?

A reduction in grazing time also equals a change in diet and this may also influence colic risk. However there are some factors relating to grazing that are potentially beneficial for digestive health. Firstly the company of other horses may in some instances serve to reduce stress levels compared to being isolated in a stable. Secondly, a horse at grass will eat little and often more or less continuously throughout the day – a behaviour known as trickle feeding. The horse’s digestive tract functions at its best when there is a continuous trickle of fibre through it and being at grass is conducive to this. Finally, continuous movement whilst grazing encourages the peristalsis action in the gut that keeps everything moving through the digestive system.

Top Tips for Managing the Risk of Colic in Horses When Grazing Is Limited

  • Where possible make all dietary changes gradually
  • Ideally offer forage ad-lib
  • For good do-ers who gain too much weight on ad lib forage reduce intake to a minimum of 1.5% of bodyweight on a dry matter basis. Divide the forage ration into several meals daily, using small holed nets to slow the rate of intake
  • Ensure free access to water and make sure your horse is drinking. Veteran horses need particular attention in the winter months where the addition of some warm water to a cold water bucket may encourage them to drink more
  • Make sure your horse’s teeth are in good condition with regular dental check-ups
  • If appropriate encourage movement in the stable by positioning forage nets in multiple locations or by using a forage/treat ball filled with Dengie’s high fibre Alfalfa Pellets or Pure Grass Pellets as a tasty low starch treat
  • For fussy feeders multiple forage sources can encourage them to consume more and spend longer engaged in foraging activity. Bring the paddock into the stable by offering a bucket of Dengie Pure Grass, Meadow Grass with Herbs or soaked Pure Grass Pellets alongside the usual forage ration


Hay Horse Feed

Colic in Horses & Concentrate Feeding

Tinker et al., (1997) reported that feeding 2.5-5kg of concentrates each day significantly increased the risk of colic in horses. What links concentrate feeding and colic risk?

The horse has a limited capacity to digest starch in their small intestine. Starch escaping digestion in the small intestine ends up in the hind gut where it is rapidly fermented. This rapid fermentation produces a more acidic environment in the gut allowing substances that shouldn’t pass through the gut wall to do so. In addition to this a more acidic environment in the gut is not favourable for fibre fermenting bacteria to survive and so fibre digestion is compromised. These factors combined are linked to an increased risk of colic.

How to Manage Colic Risk When Feeding Concentrates

  • Limit meal sizes to no more than 2kg for a horse dividing larger amounts of concentrates into 3-4 feeds daily to keep meal sizes small
  • Limit starch intake to less than 1g of starch per kg of bodyweight per meal or 2g of starch per kg of bodyweight per day
  • Use concentrate feeds that contain cereal grains that have been cooked by micronizing or extruding which enhances the digestibility of starch in the small intestine
  • Maintain a minimum forage intake of 1.5% of your horse’s bodyweight on a dry matter basis no matter how hard they are working.
  • Use early cut hay or haylage to make a more significant contribution to energy requirements to reduce the reliance on concentrates and thus the risk of colic in horses
  • Use more digestible sources of fibre such as alfalfa and sugar beet, such as Alfa-Beet or feeds that are high in oil as part of the bucket feed to reduce the reliance on cereal based concentrates. Alfalfa naturally has a calorie level comparable to a cool mix/cube, but when combined with oil in products like Dengie Alfa-A Oil provides as much energy as a conditioning mix/cube


Colic & Diet Change

Diet change is probably the most frequently reported risk factor for colic in horses. A sudden change in diet disturbs the bacterial population in the horse’s hind gut. Similarly to excessive levels of starch reaching the hind gut, a sudden change to the ration can result in rapid fermentation, a more acidic environment in the gut as well as compromised fibre digestion and increased risk of colic in horses.

Many horse owners will know that a change in their horse’s bucket feed requires a gradual change, but relatively speaking this makes up a small part of the diet. Under most circumstances grazing and forage form the largest part of the horse’s diet and so any changes in these will need to be managed gradually as well.

Managing colic risk with dietary change

  • Any changes to your horse’s diet should be made gradually over a minimum of at least a couple of weeks including changes to grazing and forage. Introduce increasing amounts of the new food, whilst reducing the old food in a stepwise fashion e.g. 0.5kg increase every 3 days for example
  • If your horse lives out during the summer, but is stabled over winter start to bring your horse in for short periods of time with access to small amounts of forage. Gradually increase the amount of time in the stable and forage offered so that when your horse has to be stabled they are already adapted to forage
  • If your horse lives in during the winter, but is turned out come spring this is a little trickier to manage as less grazing time doesn’t always equate to a smaller intake. Consider the use of a grazing muzzle combined with limited turnout, but increasing amounts of time at grass to gradually allow your horse’s digestive system time to adapt.
  • Try to stick to roughly a similar time of feeding every day to manage the risk of colic in horses
  • If your horse is away from home, take your own feed and forage with you if possible
  • During times of dietary change or travel to competition consider the use of a digestive supplement. Look for products with prebiotics and probiotics or live yeast to support the friendly fibre fermenting bacteria in your horse’s gut.

Would you know how to REACT if your horse had colic?

The British Horse Society and the University of Nottingham have created a REACT now to beat colic campaign. They provide lots of useful information including how to identify the signs of colic in horses and what to do in case of an emergency.