AN ILL WIND FOR EQUINE EYES

Research from Colorado State University suggests that high winds may contribute to the development of a potentially devastating fungal eye infection in horses.

Equine ulcerative keratomycosis (EUK) typically develops after trauma causes an ulcer or another defect in the cornea, the transparent layer of tissue that covers the front of the eye. In addition to pain and excessive tearing, EUK may lead to vision loss. In severe cases, surgical removal of the eyeball may be necessary.

To investigate whether ambient temperatures, humidity, wind speed and other environmental factors influence the development of EUK, the researchers reviewed the case files of 61 horses seen at the CSU hospital for corneal ulceration over a 15-year period. In 10 of the study horses, an EUK diagnosis was confirmed based on laboratory tests.

Analysis of those cases revealed that the highest prevalence of EUK cases occurred during two seasons, with 50 percent of the cases diagnosed in the spring and 40 percent in the fall. Only one EUK case was reported in summer, and none occurred during winter.

Despite the seasonal variations, the only environmental factor found to have a significant statistical correlation with the development of EUK was wind speed, with higher gusts correlated to greater rates of diagnosis. The researchers say this can be attributed to micro-traumas caused when airborne dust particles or vegetative fragments contaminated with fungus impact the cornea.

Reference: “Prevalence of equine ulcerative keratomycosis in Colorado and association of environmental factors: A retrospective and descriptive study (2002-2017),” Reported in Equine Veterinary Education, October 2019