So what are the chances a horse (not a speck of Appy in her pedigree) who was diagnosed with ERU as a several-weeks-old foal, could have a NON-genetic form of this? If it's of genetic origin, I don't want to breed her and have it show up in her foal. Apparently there is not a genetic screening test available at this time or I would look into that.
Lisa, I'm so sorry your mare is so far along with this condition. Fortunately, ours does not have severe symptoms (some tearing at times, but not a lot) and eyesight seems fine at age 5 years. Her eyes do have a slightly protruding look, and if you look down from above her, the eyes look clear instead of dark where they protrude. Viewed from the side, her eyes are dark brown and normal looking. During the times when the eyes are running, should she be getting anything for discomfort? She does not act like she's feeling any different at those times. The vet didn't seem overly concerned and just left a tube of eye antibiotic cream in case they looked irritated.