EQUUS CONSULTANTS

• A common eye problem

• Cushing’s and immune function

• Special handling for arthritic horses

• Risk of tendon reinjury

• Onion dangers

Q:My mare, now almost 20, gets conjunctivitis at least once each summer. It seems to occur when the weather is particularly hot and dry. When it happens, her eye swells shut within hours. My veterinarian has assured me that my mare does not have uveitis and he gave me an ointment that clears up the problem in a few days. Still, it’s unpleasant for her, and it can interrupt my riding plans. Is there a reason my mare might be more susceptible to this than the other three horses in her pasture (who don’t seem to have this problem)? Are there steps I can take to help prevent this? Stacy Brennan Carlsbad, New Mexico

A:Conjunctivitis in horses is relatively uncommon compared to how frequently the condition is observed in dogs and people. Often referred to as “pinkeye,” conjunctivitis is the inflammation of the tissue around the eye. Horses may have red conjunctiva, mild discomfort and slight watery or mucous discharge.

In horses, conjunctivitis is usually caused by minor and self-limiting bacterial or viral infections. But the condition can be associated with another primary underlying cause, such as corneal disease or uveitis, an inflammation of the pigmented structures within the eyeball.

Therefore, anytime a horse owner notices “pink eye” or ocular discharge of any type, it is important to have an experienced veterinarian give the horse a complete eye examination, just as you’ve done. Although conjunctivitis

itself rarely leads to long-term problems, the potential underlying causes can result in blindness.

As for preventing the condition, you can try fitting your mare with a fly mask, which will block wind, dust and insects that may be irritating the eye and triggering the reaction. Brian Gilger, DVM, MS,

DACVO, DABT North Carolina State University Raleigh, North Carolina