The most common form of equine blindness is
Equine Recurrent Uveitis (sometimes called Moon Blindness)
We have witnessed so many cases of ERU, sadly.
Various things bring about uveitis, but once it happens, the question is. . .will you end up dealing with the ERU and what was the cause?
For us, if it there is still vision, it is worth trying to save the eye and to see whether the issue will prove to be uveitis or (more typically) the reoccuring form. This process is painful for the horse, to be sure.
The horses that have come to us have already lost vision from untreated uveitis. They are too far progressed to have vision to save at all. Over the years, I have networked various ERU cases that were bacterial, or from a virus or a protozoa, and as a rule, when anything but trauma causes blindness, both eyes end up affected and the vision is lost for good in both.
The question then becomes an ethical one in cases of ERU.
The horse is blind in one or both eyes, and it is painful if you’re dealing with ERU. It reoccurs, hence the name. It is hard to say how often, but it is a life long management issue.
The horse will keep the eye from slightly to very squinted, it will drain, they may blink more often with it flares or all of the time.
Many lay people do not realize how very painful this is for the horse. They think the horse is doing fine. But this isn’t the case. Imagine if you have scratched your cornea before (I know I have) and the pain you were in. . .except in a week, your injury heals.
So, in horses with ERU, it keeps coming back or sometimes never really stops.
Yes, you can manage the condition to some degree with medications daily for the life of the horse, but even that is still “managing pain” rather than ending the pain for good.
People dislike and shrink from horses with an eye removed, but the horse breathes a sigh of relief.
The pain is over for them, then.
Lettie, below, came to us with Trauma Induced ERU, as as guess by our vet. She has had this for at least 6 years. I’ll grant that apart from some tearing and light squinting, some people wouldn’t have realized how much pain she was in. We knew she was though. The vet who did her surgery was so pleased that we did not care about the “look” and that we knew she was in pain and wanted the eye removed to make her comfortable.
Until seeing her after, the average person wouldn’t have realized how much pain that blind eye was causing her, but the difference was so evident in her when it was, even to those who may not have understood how she was suffering before.
If you have an ERU case and notice the tearing and even faint squinting, please do not let the aesthetics prevent you from giving your horse this surgery if the vision is already lost as opposed to leaving it be or doing daily management with medications.
The quality of life is so much better for the horse who receives it!