What is winter colic?

Winter colic, a common condition associated with the colder months, is an impaction colic. The horse’s intestine gets blocked with feedstuff and other material, usually from a lack of fresh water and moisture-rich fresh grass which causes dehydration. Dehydration impedes gut movement, which can result in a blockage. Feed and gas build up behind the blockage, and cause distention of the horse’s intestine and associated pain. Impactions can occur anywhere throughout the intestine, however, the pelvic flexure portion of the large intestine is one of the more common sites due to the decreased diameter at this point.

Symptoms of winter colic:

• Frequently looking at their side
• Biting/kicking their flank or belly
•  Lying down and/or rolling
• Little or no passing of manure, faecal balls smaller than usual, and/or passing dry or mucus (slime)-covered manure
• Poor eating behaviour (eats less grain/hay) & a change in drinking behaviour
• Changes in vital signs – heart rate of over 45 to 50 beats per minute, tacky gums and a long capillary refill time

Avoiding winter colic

• Your horse should always have access to fresh clean drinking water so, when temperatures drop, it can get difficult as water buckets or drinkers can freeze over.  Make sure that water is fresh and not frozen all day, also check that the footing to the water trough is not frozen. Some horses will not drink really cold water so offer them a bucket of water that has been warmed. Ways to increase moisture intake include feeding soaked hay and wet feeds.
• Keep to a scheduled daily feeding routine as much as is possible. Make any changes gradually. Especially be aware of swapping from hay to haylage (and vice versa) and make sure that this is done very slowly and with great care. As far as the bugs in the horse’s gut are concerned there is a very big difference between hay and haylage and many an upset stomach has been caused by a rapid swap. Feeding a prebiotic, whenever change or potential stress arises, will support the microbial populations of the hindgut and help avoid upsets.    If weather conditions force a change in the routine & stable usage, keep a look for signs of colic.
• Feed plenty of forage/fibre as not only does ad lib forage provide calories and other nutrients, and heat during its fermentation in the hind gut, it also provides physical bulk in the digestive tract to encourage gut motility and potentially reduce the risk of twists or intussusceptions, which could occur if portions of the gut are empty. Your horse should always have some form of forage or fibre to chew as long periods with nothing to eat can risk gastric ulcers as well as colic. Hopefully, your horse has daily access to grazing but, when grass quantity diminishes, providing hay or haylage in the field is essential to keep your horse chewing and fibre flowing through the gut.
• Turn your horse out as much as possible. The horse is not designed for a sedentary lifestyle and physical movement is essential to keep the gut functioning and its contents moving so, if turnout is limited and your horse is confined to the box, even a walk round the yard is better than nothing.  
• Make sure you have an effective worming program in place. Especially make sure that your horse is wormed against small encysted red worms in December/January.

Diagnosing and treating winter colic

• Winter colic is typically easy to diagnose, mostly during rectal palpations. Treatment normally includes painkillers along with hydration to get things moving again. If the impaction is more severe, your horse may need to be hospitalised so that intravenous fluids can be administered.

If you spot any signs of colic in your horse please call us immediately.