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 – nutritionist at Castle Horse Feeds gives us seven essential steps to take when feeding your horse to reduce the risk of colic.
signs of colic
1) Forage first!!
Forage should always be the foundation of your horse’s diet, 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: 
Firstly, a constant supply of forage travelling through the digestive tract keeps it moving to reduce 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 bodyweight per day to maximise digestive health.  Research has shown that forage fed horses have a more stable and balanced microbial community and this is important given that an unstable microbial community and potential microbial dysbiosis is an important risk factor for colic. Feeding plenty of forage keeps the gut microbes happy and healthy and healthy microbes = a healthy horse!

2) 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 provide, it’s best to supply that through sources of highly digestible fibre like unmolassed sugar beet and soya hulls.  When additional energy is required, this 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. 

3) Ensure dietary changes are gradual
Abrupt dietary changes are an important risk factor for colic, so it’s important to ensure these changes are very gradual. When introducing any 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 fructan reaching the hindgut, potentially causing microbial dysbiosis, so the change still needs to be very gradual to help reduce the risk.

4) Feed little and often – in sympathy with the digestive system
Feeding large, infrequent meals poses a higher risk for colic through imbalances in microbial populations and fermentation and by significantly reducing gut mobility.  Therefore, making sure you feed your horse on a little and often basis is an important strategy to help negate this risk. By mimicking the horse’s natural eating habits and feeding in sympathy with the digestive system, to provide a more constant supply of smaller feeds, you can help reduce the overall risk of colic by optimising digestive health. 

5) Ensure your horse has regular access to grazing and turnout
Free access to grazing is beneficial to digestive health because it mimics a natural diet and allows horses to carry out normal eating and social behaviours along with gentle exercise. Pasture turnout has generally been found to reduce the risk of colic, which in turn, increases when horses are stabled.  So, to minimise the chance of colic, it’s important to make sure your horse is turned out regularly, ideally for more than 12 hours per day. 

6) Make sure your horse gets enough water
Water is key in helping to prevent colic because it helps stimulate gut motility. Making sure your horse drinks enough water is therefore essential.  Adding salt to feed is ideal to encourage drinking and adding hot water to warm up your horse’s drinking water in winter can also help maximise water intake. 

7) Consider digestive enhancers
Yeast based prebiotics have been shown to stimulate the growth of beneficial hindgut microbes, to help stabilise the gut microbe population and enhance fibre fermentation. A stable, balanced microbial population, along with enhanced fibre digestion should help reduce the risk of colic so feeding a balancer or feed containing these prebiotics could be beneficial. 
If you have any questions about how to create the best diet for your horse, email This email address is being protected from spambots. You need JavaScript enabled to view it. or call 01497 570345. See www.castlehorsefeeds.com for further information and to sign up for free nutrition news and insights.
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