Colic

Does Barometric Pressure Cause Colic?

By Adam Marcus

A recent study lets the air out of the notion that barometric pressure is associated with the risk for colic in horses.

Although barometric pressure was not linked to the risk for colic, the study did find an association between higher latitude and seasonal weather changes—particularly spring, summer and fall, which can be volatile in the Mid-Atlantic states—and gastrointestinal illness in horses. However, the veterinarians said this effect likely reflects the way horse owners and stables manage their animals rather than any direct impact of weather on GI health.

“Although barometric pressure changes were not found to be significantly associated with the diagnosis of colic in our analysis, seasons with changing weather in the mid-Atlantic region were,” said Ashley Boyle, DVM, an associate professor in the School of Veterinary Medicine at the University of Pennsylvania, and leader of the study team.

“We are extrapolating that human management changes may be playing a role in this, so minimizing disruptions in management of the horses is advised.”

For the study, Dr. Boyle and her colleagues examined electronic veterinary records of 11,601 horses treated in the Penn system between January 2005 and January 2017. To look for an effect of barometric pressure on health outcomes, they matched pressure readings from weather stations located in the geographic region where Penn equine vets practice.

Barometric pressure has been tied to certain medical problems for both people and animals, but in this study, it was not associated with the risk for colic or other health issues in horses, Dr. Boyle’s group found. But animals were significantly more likely to develop colic in the spring, fall and summer than in winter, they reported (odds ratios of 1.29, 1.72 and 1.85, and P=0.04, P<0.0001 and P<0.0001, respectively).

Interestingly, the researchers found that every 1° increase in latitude was linked to a 2.4% increase in the risk for colic relative to other equine complaints, including esophageal choke, cuts, lameness and eye conditions. In the Northern Hemisphere, where the study was conducted, rising latitude generally means colder winters. Horses have been shown to drink less water during cold weather—potentially leading to dehydration, which is a known risk factor for colic, as well as reduced ileal contractility, Dr. Boyle’s group said.

For more information:

Cianci J et al. Lack of Association between barometric pressure and incidence of colic in equine academic ambulatory practice. J Equine Vet Sci 2021;97 February 2021, 103342 https://doi.org/10.1016/j.jevs.2020.103342 https://www.sciencedirect.com/science/article/abs/pii/S0737080620304330