As the days shorten and the weather turns, most horse owners focus on rugs, hay supplies and frozen troughs. Colic is often thought of as unpredictable, something that strikes without warning at any time of year. However, many of the changes that come with winter are recognised risk factors for colic, and a large number of them are within an owner's control.
Colic is the most common reason for emergency veterinary treatment in horses (Curtis et al., 2019). A review of the research on colic risk found that the strongest evidence for management-related risk relates to change, with recent changes in feed and housing forming the largest bodies of evidence (Curtis et al., 2019). Winter brings both. Horses move from grass to hay, spend more time stabled, often exercise less and may drink less as water becomes colder.
For owners, the aim is therefore not to avoid winter management changes altogether, which is rarely possible, but to manage them carefully. The following steps outline practical ways to reduce the risk of colic through the colder months.
Why winter increases the risk
The horse's digestive system is designed for a steady intake of forage, regular movement and a consistent routine. Winter tends to disrupt all three at once.
Research from the University of Nottingham tracked horses as they moved from full-time grazing to a stabled routine with light exercise. Although the horses drank more water once stabled, their droppings became drier and fewer, and gut activity in the large colon was reduced. These changes were most marked during the first five days after the move (Williams et al., 2015).
An earlier UK study of horses admitted to referral hospitals found that a type of colic involving obstruction of the large colon was associated with an increase in time spent stabled and a reduction in exercise in the preceding two weeks (Hillyer et al., 2002).
1. Make feed changes gradually
The switch from grass to hay or haylage is one of the biggest dietary changes a horse makes all year. Wherever possible, it should be made gradually over a couple of weeks, rather than overnight.
In practice, this means starting to introduce hay while horses are still grazing, and increasing it as grass quality drops. The same applies to changes between batches of hay or haylage, which can differ considerably in nutritional value and moisture content. Mixing a new batch with the old one for a period helps the gut adjust.
Changes to hard feed should be made in the same gradual way. If a horse's workload drops over winter, its feed ration may need to be reduced to match. Your vet or a qualified nutritionist can advise on the right approach for an individual horse.
2. Keep turnout going where you can
Because an increase in stabling is linked with colic risk (Hillyer et al., 2002; Curtis et al., 2019), maintaining some turnout through winter is one of the most useful things an owner can do. Where turnout has to be reduced, a gradual transition is preferable to a sudden change (Williams et al., 2015).
Mud is often the main reason turnout stops. Gateways, feeding areas and tracks become poached and unsafe, and fields may be closed to protect the land. Stabilising these high-traffic areas can make it practical to keep horses out for longer. Jelka's HIT Top Clean mud mats are designed for gateways, feeding areas and track systems, giving horses a firm, free-draining surface to stand and move on, even when the surrounding ground is wet.
Laying mats is best done in early autumn, while the ground is still firm enough to keep them level.
3. Maintain regular exercise
Reduced exercise is another change associated with colic (Hillyer et al., 2002), and it often comes hand in hand with reduced turnout. Short days, frozen or waterlogged arenas and busy schedules can all mean horses go several days with little movement.
Where possible, keep exercise consistent rather than stopping and starting. Even light daily work, such as walking in hand or on a horse walker, keeps the horse moving. For yards where weather regularly limits riding, an equine treadmill offers controlled, consistent exercise regardless of ground conditions. It also allows workload to be adjusted gradually rather than changed suddenly.
4. Encourage horses to drink
Horses generally drink less when water is very cold. In a study of ponies kept in cold conditions, they drank around 40% more when offered warmed water than when offered near-freezing water (Kristula and McDonnell, 1994). Interestingly, when both were available, the ponies tended to choose the cold water but drank less of it overall.
Reduced water intake matters because dry forage requires more water to digest, and impaction colic is associated with the gut contents becoming too dry. Practical steps include:
checking troughs and buckets at least twice a day and breaking ice
insulating pipes to troughs to reduce freezing
adding warm water to buckets in very cold weather
monitoring how much stabled horses are drinking, so any change is noticed early
Soaking hay or adding water to hard feed can also increase overall water intake, though this should be discussed with your vet if a horse has specific dietary needs.
5. Feed forage off the ground
When hay is fed in the field, horses inevitably pick up soil or sand along with it, especially where the ground is bare or poached. Research on horses kept on sandy soils found that feeding directly on the ground increased the risk of sand being present in the droppings when combined with short or no grass (Husted et al., 2005). Over time, sand can build up in the gut and, in some cases, cause impaction.
Feeding forage from racks, haynets or feeders reduces the amount of dirt picked up. Placing feeding areas on a firm surface that can be swept clean helps further. HIT Top Clean mats are designed for use in feeding areas and can be kept clean more easily than bare ground. Moving feeding points regularly also prevents one area from becoming heavily poached.
6. Keep up with routine health care
Winter is a good time to check that routine care is up to date. Dental problems can affect how well a horse chews its forage. Poorly chewed fibre is harder to digest, which is particularly relevant when horses move onto a hay-based diet. Your vet can also advise on a worming plan based on faecal egg counts and the time of year.
Body condition should be monitored throughout the winter. Changes in weight can be a useful early sign that a horse's feed, workload or health needs attention.
7. Know the early signs
Even with good management, colic cannot always be prevented. Recognising the early signs allows the vet to be called sooner. Signs include restlessness, pawing the ground, looking round at the flanks, lying down more than usual, reduced appetite and fewer droppings than normal.
If colic is suspected, contact your vet immediately. It is also worth keeping a simple note of each horse's normal behaviour, water intake and droppings over winter, as this makes changes easier to spot.
Conclusion
Much of the increased colic risk in winter comes from change: in diet, housing, exercise and water intake. Winter management inevitably involves some of these changes, but they do not need to happen all at once or without preparation.
The key points are to make changes gradually, keep horses moving and turned out wherever conditions allow, and pay close attention to water intake. Practical infrastructure can support this, from stable, mud-free feeding and turnout areas to options for consistent exercise when the weather limits riding.
Every horse is different. Any concerns about an individual horse's diet, health or colic risk should always be discussed with your vet.
For advice on creating mud-free turnout and feeding areas, or on equine treadmills, contact the Jelka team.
References
Curtis, L., Burford, J.H., England, G.C.W. and Freeman, S.L. (2019) 'Risk factors for acute abdominal pain (colic) in the adult horse: a scoping review of risk factors, and a systematic review of the effect of management-related changes', PLoS ONE, 14(7), e0219307. doi: 10.1371/journal.pone.0219307.
Hillyer, M.H., Taylor, F.G.R., Proudman, C.J., Edwards, G.B., Smith, J.E. and French, N.P. (2002) 'Case control study to identify risk factors for simple colonic obstruction and distension colic in horses', Equine Veterinary Journal, 34(5), pp. 455–463.
Husted, L., Andersen, M.S., Borggaard, O.K., Houe, H. and Olsen, S.N. (2005) 'Risk factors for faecal sand excretion in Icelandic horses', Equine Veterinary Journal, 37(4), pp. 351–355.
Kristula, M.A. and McDonnell, S.M. (1994) 'Drinking water temperature affects consumption of water during cold weather in ponies', Applied Animal Behaviour Science, 41(3–4), pp. 155–160. doi: 10.1016/0168-1591(94)90020-5.
Williams, S., Horner, J., Orton, E., Green, M., McMullen, S., Mobasheri, A. and Freeman, S.L. (2015) 'Water intake, faecal output and intestinal motility in horses moved from pasture to a stabled management regime with controlled exercise', Equine Veterinary Journal, 47(1), pp. 96–100. doi: 10.1111/evj.12238.