Colic is one of the main fears of many horse owners. Basically, colic is anything that causes abdominal pain in a horse. There are many potential causes of colic that can range from something as simple as gas cramps to something as serious as a twisted section of the intestine. While some causes are spontaneous and unpreventable, there are steps you can take to decrease the risk of other colic causes, such as impaction colic.

In simple terms, an impaction colic is a form of constipation. Dry, hard fecal material builds up in the colon, causing a blockage that will not move through the digestive tract. Often, this occurs in the pelvic flexure of the large colon (If you’re interested in the journey of food through your horse, watch this video: https://www.youtube.com/watch?v=fdz78HU_fkM, the pelvic flexure is where the left dorsal colon turns to the right dorsal colon!) and can felt on rectal palpation by your veterinarian. Signs of impaction colic include dullness, depression, decreased appetite, discomfort, increased laying time and dry, hard manure or no manure. If caught early, impaction colic is often treatable with fasting, oral fluid therapy and pain management. Severe or advanced cases may require hospitalization for IV fluids or, less commonly, surgery.

So, what causes impaction colic? The main risk factor is decreased water consumption (other factors include poor hay quality, internal parasites, decreased exercise, and dental problems)! During cold winter temperatures, horses do not want to drink as much water. Decreased water intakes mean that the feed material passing through the digestive tract is drier, increasing the risk for impaction.

https://aaep.org/horsehealth/winter-water-consumption