Steps to reduce the risk of colic through feeding

Steps to reduce the risk of colic through feeding from nutritionist Lisa Elliot, MSc

Did you know you can reduce the risk of colic by feeding your horse correctly?

Horses have a unique digestive system, finely tuned to efficiently digest a constant supply of low starch, fibrous feed. Domestication and modern horse management have meant that horses are sometimes fed very nutrient-dense diets that the digestive system is not well adapted for.

Unfortunately, a less-than-natural feeding regime can result in potential digestive health problems, one of which is colic. Colic is one of the most serious conditions a horse can suffer and can be life-threatening.

However, the chances of your horse getting colic can be decreased with the right feeding principles. Lisa Elliot, MSc, gives us her essential tips to consider when feeding your horse to reduce the risk of colic.

Forage first!

Forage should always be the foundation of your horse’s diet, and it should be fed on an ad-lib basis to support good digestive health. Providing good-quality forage with higher digestibility is key because the less digestible a forage, the more the risk of colic will increase. Ad-lib good-quality forage will help reduce the risk of colic in two ways:

• A constant supply of forage travelling through the digestive tract keeps it moving, reducing the risk of feed getting stuck in the more ‘bottle neck’ areas of the gut and potentially causing an impaction.
• Secondly, a constant supply of forage promotes the growth of beneficial microbes and helps support microbial equilibrium in the hind gut.

Forage should never form less than 70% of the horse’s diet or 1.5% of body weight per day to maximise digestive health. Research has shown that forage-fed horses have a more stable and balanced microbial community. This is important given that an unstable microbial community and potential imbalances are important risk factors for colic. Feeding plenty of forage keeps the gut microbes happy and healthy and healthy microbes equals a healthy horse!

Keep starch to a minimum

Whilst cereals provide a reliable source of energy from starch for those horses that need it, overfeeding them can heighten the risk of colic. Excess starch which reaches the hindgut can result in hindgut acidosis and microbial dysbiosis due to rapid microbial fermentation. Both of these are risk factors for colic, so it’s important to keep starch levels to a minimum. 

Ideally, the amount of starch fed per meal should be no more than 2g per kg bodyweight (BW) per meal, but to help further reduce the risk, cereal-based meals can be divided into smaller meals so that the horse receives only 1g per kg BW per meal.

If your horse is in a level of work that requires more energy than forage alone can, it’s best to supply that through sources of highly digestible fibre like unmolassed sugar beet and soya hulls. When additional energy is required, it can also be supplied through sources of oil such as linseed meal. To reduce the risk of colic from cereal starch, fibre should always be the first choice and cereals should only be fed when the nature of the horse’s work demands it.

To reduce the risk of colic from cereal starch, fibre should always be the first choice and cereals should only be fed when the nature of the horse’s work demands it.

Ensure dietary changes are gradual

Abrupt dietary changes are an important risk factor for colic, so it’s important to ensure they are gradual. When introducing new feeds, changes should be made over 2 – 3 weeks to enable the hindgut microbes to fully adjust and minimise the risk of colic, but this doesn’t only apply to bucket feeds. Research has indicated that the risk of colic is greater when a horse is changed to a new forage, for example – if switching from hay to haylage, a different batch of the same forage and when changing from winter to summer grazing.

Compared to winter grazing, spring or summer grass can be higher in non-structural carbohydrates (NSC), which can pose a colic risk due to higher levels of sugars (fructan) reaching the hindgut. The change in sugar levels can potentially cause microbial imbalances, therefore change still needs to be very gradual to help reduce the risk.