Horses that are on 24-hour turnout spend approximately 75% of the day and 50% of the night eating, whereas stalled horses are fed a fixed number of meals/day. A horse that is in its natural environment grazes for 16-20 hours a day and may travel up to 8km/day, assisting intestinal motility.

Tip: Maximize the amount of time your horse is turned out. If your horse is in a stall, ensure that he is getting exercise and sufficient hay to allow his gut to function properly.

Increased opportunity to graze is associated with reduced incidence of colic since it matches the natural activity pattern of continuous grazing. Horses evolved to have a trickle feeding digestive system in which small amounts of food are needed continuously throughout the day to keep the gut functioning properly.

Tip: Ensure that your horse has enough pasture and/or hay to eat throughout the day. If your horse is overweight, there are new feeding systems that allow feed to be dispensed slowly. A grazing muzzle can also help to limit their pasture intake.

Multiple pastures may have different grass species at varying stages of maturity which alters the nutrient composition of the pasture. Bacteria in the horse’s digestive system adapts to different types of grasses and the type of bacteria will change based on the type of grass the horse is eating. When changing pastures, bacteria need time to change and adapt to the new types of grasses. If there is not enough time for the bacteria to adapt it can cause digestive disturbances.

Tip: If possible, turn your horse out in pastures that contain similar grasses at same stage of maturity. If changing pastures, it is recommended to have a 14 day adaptation/transition period to allow the gut bacteria a chance to adapt to the new grasses.

Higher stocking density reduces the amount of pasture available for each horse and also increases the amount of parasite eggs that are shed (increasing the chances of parasite infection).

Tip: A general guideline of 1 horse per 2.5 acres is the minimum recommendation to ensure sufficient pasture for each horse. This will also depend on your pasture management, soil and climate in your area. In some regions, this could be as high as 10 acres per horse.

Horses that are eating off sandy soil (i.e. sandy paddock/pasture or an arena) are more likely to accidentally ingest sand. Accumulation of sand in the horse’s gastrointestinal tract can lead to impaction and colic.

Tip: If you are located in a sandy region, feed your horse off the ground with raised hay feeders to minimize ingested sand.

Performance horses tend to be involved in certain activities that are associated with stress and have shown to increase the risk of colic. 80-100% of racehorses are known to have gastric ulcers which can also lead to colic.

Tip: Be conscious about trying to minimize the stress and anxiety in your horse’s life.

People that care for their own horse are more likely to be aware of changes in behaviour and feeding patterns since they know their horse the best!

If multiple people are caring for your horse, subtle changes in your horse’s behaviour or feeding may be missed since they may not see gradual daily changes.

Tip: Have a log for your horse in which caregivers can makes notes to pass along information to the other caregivers.

Early colic signs such as changes in behaviour and feeding are more likely to be detected if your horse is being monitored often throughout the day.

Tip: It is recommended that you monitor your horse at least 2x/day, however the more often the better!

Horses evolved to eat a forage-based diet with little to no concentrates. A high concentrate diet may cause digestive upsets including gas production, changes in intestinal motility and bacterial population which can lead to colic.

Tip: Feeding lower amounts of concentrates as well as feeding smaller meals throughout the day (rather than one large meal), will help reduce the risk of colic.

A diet that is high in alfalfa hay will increase the risk of enteroliths, which are stones that are formed from crystallized minerals. These stones can cause a blockage in the large colon causing colic. However, if your horse suffers from gastric ulcers, alfalfa has been shown to have protective properties by increasing the pH in the stomach.

Tip: It is recommended not to feed over 50% of your horse’s hay as alfalfa. Discuss your horse’s hay requirements with your veterinarian/nutritionist.

Mouldy hay, sometimes associated with large round bales, contains dust and mycotoxins that can increase colic risk.

Tip: Providing good quality hay that is free of irritants such as dust and mould will reduce your horse’s colic risk.

Inadequate water supply has been associated with an increase in colic risk. Having fresh, clean water source is important in decreasing risk of colic as it encourages water intake.

Tip: Observe your horse’s behaviour to ensure that he and all the other horses are able to access the water, as sometimes in small paddocks one horse may prevent other horses from getting to the water source. Avoid using water buckets as the outdoor water source since they are more likely to run out of water.

A heated water source in the winter will prevent water from freezing and will also encourage drinking.

Tip: Monitor your horse’s water intake and signs of dehydration. A “skin pinch” on the shoulder of the horse is a useful tool to assess hydration. To do this, you pull the skin away and release to see if there is any delay in the skin flattening back down (this is called skin tenting).

Reduced chewing of feed due to dental problems will lead to larger particles and undigested feed ingredients entering the horse’s gut. Undigested feed and longer fibre particles may reach the hindgut - increasing the risk of impaction.

Tip: Observe your horse’s chewing when he is eating. If there any abnormalities such as difficulty chewing, feed coming out of his mouth or excess salivation contact your veterinarian for a dental check-up.

Digestion is impacted if a horse is unable to grind food properly due to sharp edges or other dental problems.

Tip: Schedule regular dental checkups with your veterinarian to make sure your horse’s teeth are aligned with no jagged edges.

Parasites can cause motility disturbances, inflammation and blood clots in the gastrointestinal tract – all of which can cause colic.

Tip: Performing a fecal egg count is an important part of an overall parasite prevention program. Having a fecal egg count of 200 strongyle eggs/g of feces has been shown to decrease the risk of colic. Talk to your veterinarian about developing an effective prevention program.

Horses that have been recently dewormed are at a slightly higher risk of colic due to the associated purge of worms that could cause an impaction. This effect is more commonly seen if a horse has a heavy worm burden, especially if the horse has not been on a good deworming program.

Tip: After deworming, monitor your horse closely for signs of colic. Performing fecal egg count test (FECT) will assess whether your horse has a high parasitic infection.

With the rise of dewormer resistance, it is important to include other management techniques in your parasite prevention program.

Tip: Removal of manure from pastures, pasture rotation or co-grazing with other ruminants will help reduce parasite populations in pasture.

Horses that have had previous colic episodes are at higher risk of having another colic episode, particularly those that underwent surgery.

Tip: Notify other caregivers about your horse’s colic history and closely monitor your horse for early colic signs. Assess your management practices and identify high risk areas that you can improve.

Relationship between age and colic risk is complex given that colic risk may be more an indicator of activity level and feeding rather than the age of the horse. However, certain types of colic are more prominent in different age groups (i.e. geriatric horses are prone to develop strangulated lipoma which can cause colic).

Crib-biting may not directly cause colic, but could be a marker for other management practices and temperament (i.e. stress, less time grazing/eating when cribbing). Cribbing will also cause teeth to become worn/damaged - impairing chewing capacity.

Tip: Monitor your horse for early signs of cribbing. It is often easier to stop the behaviour in its early stages. Providing free access to hay may help alleviate boredom that could be triggering the cribbing behaviour.

Trailering your horse can sometimes be a stressful event, increasing the risk of colic. Horses that travel long distances may be at an even higher risk of colic.

Tip: Monitor your horse every few hours while trailering and ensure that your horse is eating and is well hydrated. It is also recommended that your horse is walked every few hours.

There is an increased risk of colon displacement particularly during peri-parturient period (close to or after foaling).

Tip: Observe your broodmare closely before and after foaling for colic signs. Ensure she is well hydrated and drinking since her water requirements have increased for milk production

Any change in a horse’s diet, whether it is the quantity or type of the feed or the feeding schedule, will increase your horse’s risk of colic.

Tip: It is recommended to provide a 2-week adaptation/transition period when introducing new feed to your horse’s diet to allow gut bacteria and enzymes a chance to adapt to the new feed.

Bacteria in the horse’s digestive system adapts to different types of hay and the type of bacteria will change based on your horse’s diet. When changing batches of hay, bacteria need time to change and adapt to the new hay. If there is not enough time for the bacteria to adapt it can cause digestive disturbances which can lead to colic. Be prepared before you switch your horse’s hay. Ensure that you have enough of the old hay to mix in with your new hay during the adaptation/transition period.

Tip: Be prepared before you switch your horse’s hay. Ensure that you have enough of the old hay to mix in with your new hay during the adaptation/transition period.

A decrease in water intake will predispose your horse to impaction colic as the feedstuff going through the gut is 'more dry'.

Tip: Pay attention to water intake, particularly during weather changes. If you are using an automatic watering system, a water consumption meter will help monitor water intake.

It is believed that the stress associated with a new environment may increase colic risk. Changes in housing can also be associated with a change in diet (new pasture, different hay batch).

Tip: If possible, make changes to housing slowly as to minimize stress and digestive upsets. When changing barns, try to bring some 'old' hay that you can mix in with the new hay.

Tip: If possible, transition your horse to his new routine by slowly increasing/decreasing the amount of time your horse spends in a stall. A change of 1 hour/day is recommended.

It is believed that colic risk could also be associated with changes in diet/stabling that is often seen when changing activity level.

Tip: When there is a change in activity level, be sure to make changes slowly to your horse’s exercise routine, stabling and diet.

Although it is not known why a sudden change in weather increases colic risk, it is suggested to be linked to changes in drinking behaviour due to the sudden temperature change. (i.e. the horse will drink less when it suddenly becomes cold).

Tip: Monitor your horse’s water intake during sudden weather changes and between seasons – especially in the fall when horses are shifting from a high moisture diet (grass) to a low moisture diet (dried hay).