Do storms raise colic risk?

Q: Are there any established links between barometric pressure and colic? I hear about an increase in colic cases every time we have a fastmoving winter storm in our area. Is the atmospheric change triggering colic? Jill Davidson

Quincy, Massachusetts

A: Your question about potential links between colic and changes in weather---and associated changes in barometric pressure---is a good one. Overall, some connection is believed to exist but it has more to do with how equine behavior can be affected by the environmental conditions. The idea is that horses have different exercise and eating patterns when the weather changes. For instance, a horse may move into a run-in shed or be brought into a stall and stay relatively stationary during rainy weather. Horses may also stop eating and drinking during a storm. The combination of reduced exercise and lower food and water intake may set off a colic episode.

An article in the May 2018 issue of EQUUS titled “Weather-Related Colic” (Hands On, EQUUS 488) suggested that when barometric pressure drops, it can lead to an expansion of the gas within the colon, thereby triggering colic, but the authors indicated that there is no scientific agreement on the premise.

A more definitive relationship has been shown between a drop in barometric pressure and onset of gastric dilatation volvulus (GDV) in dogs, which is the most severe form of canine abdominal distress. This suggests that in the more controlled environment of a dog’s body, barometric pressure does have an association with increases in gas accumulation in the gastrointestinal tract, and the big saclike organs (the stomach in dogs) would be the most likely to be affected.

When it comes to horses, some studies have noted a significant relationship between changes in the weather and incidence of colic, whereas others suggest that more specific weather variables are associated with digestive upset.

For example, in one study from northern Greece, abrupt increases in temperature in the fall and spring were observed to have a significant effect on colic incidence. Similarly, an Austrian study noted an association between colic and high temperatures on the date of arrival at an equine hospital. The likelihood is that the horses in these

Some studies have noted a relationship between changes in the weather and incidence of colic, while others suggest that more specific weather variables are associated with digestive upset in horses.

studies changed their drinking behavior during hot weather. Similar responses to extremely cold weather also can lead to colic.

The take-home message is that changes in weather that affect a horse’s exercise, eating or drinking patterns are likely to be associated with an increased incidence of colic, and owners should think about taking precautions, such as increasing the supply of fresh water when it’s hot, as well as providing shelter and good quality hay. It’s also wise to check your horse carefully after a storm to make sure he is eating and drinking sufficient water (the normal amount for a horse is six gallons/day during temperate weather). If you notice a lack of interest in food or signs of discomfort after a change in weather, call your veterinarian without delay.

Anthony Blikslager, DVM, PhD North Carolina State University Raleigh, North Carolina