Cold Weather Colic
The changing weather and changing seasons brings along with it new sets of challenges for horse and owner alike. Fall and winter bring colder weather. Colder weather brings about changes in horses turnout, eat and drinking habits. Horses have sensitive gastrointestinal tracts and these changes can cause an otherwise healthy horse to colic. Colic in itself is just a term used to describe abdominal discomfort in a horse. It does not specify the particular reason the horse is in pain. It’s our job as veterinarians to try to figure out the cause of the horse’s distress and to treat them accordingly.
Cold weather in particular seems to bring about an increase in the incidence of impaction colic. Impaction colic, by definition, is the blockage of feed material along any part of the horse’s gastrointestinal tract (GI). Horse’s have over 90 feet of bowel in their abdomens. Most of the time when we are talking about impactions in horse’s, they are occurring in the large intestine at the pelvic flexure. Here, the diameter of the lumen changes as well as it makes an abrupt turn. The mostly liquid ingesta becomes more dry, forming the manure we are all used to seeing.
The onset of cooler weather also means horses are drinking less water. This alone can cause the GI tract to dry out more, contributing to blockages forming. As the weather gets frigid and horses are eating more hay, but not drinking as well, they are more prone to becoming blocked. Activity level is another component to the problem. Often less turnout and less time being worked leads to more sedentary time, which can effectively decrease the motility of the horse’s GI tract. As an owner, identifying the signs of an impaction is key to treating it early. Often before a horse becomes impacted you will notice they are passing less manure and the manure they are passing is dry and firm. Horses often start with subtle signs, maybe just being off their feed or lying down during the day more than usual. As the impaction persists, often the signs of colic are more obvious, with a horse pawing, flank watching and rolling.
Diagnosis of impaction colic begins with a thorough physical exam and rectal palpation. If the impaction is in the common site, at the pelvic flexure, it can be felt on exam. The lack of feeling an impaction on rectal exam cannot rule out impaction somewhere else in the GI tract that is not accessible on rectal exam. The majority of impactions can be treated medically on the farm, without needing hospitalization or surgery. The goal of treatment is rehydrating the GI tract to break up the feed material and allow the horse to pass the impaction on their own. Using a nasogastric tube to administer fluids, electrolytes, oil and Epsom salts is often the first step. If the impaction is large or has been present for a while and is very hard, IV fluids are often very helpful in the rehydration process.
Regardless of the fact that impactions are usually treatable, the best course of action is that of prevention. There are a few measures that can be taken to try to help prevent a horse from becoming impacted in the first place. Encouraging your horses to drink by offering heated water in the cold months can go a long way. If you have horses that aren’t particularly good about drinking, giving them an electrolyte supplement in their feed is a good idea. There are plenty of pellets and powders available. If you choose to use a powder that goes in their water, make sure there is also clean water available without electrolytes in it. Encouraging exercise and giving horses as much turnout and activity as possible will help maintain good GI tract motility. So bundle up, get you and your horse a nice warm drink, and go enjoy some time spent outside on those nice winter days!