Eye Mystery

A while back, my foundation doe Kari developed a cloudy eye. She never had any drainage, and never acted like she had any discomfort. She is pretty old now- I believe 6 years off the top of my head- and I honestly didn't think much of it at the time. Maybe she had bumped it or it was just one of those things. As far as I can tell, Kari can't see out of it and there aren't any spots that are darker or lighter, no irritation around the membranes, etc. As the cloudy eye has persisted though, it does look like the whole eyeball has become slightly larger than the other over time. Even with this, she doesn't really favor a side, raised litters of kits perfectly, eats/drinks well, and has good condition. 

The thing is, I was "supervising" my poor husband taking care of them this week and I noticed a very faint cloudiness around Kurayami's eye towards one side. Upon closer inspection, it looks like the same kind of vague cloudiness that her Mom has, just less advanced. The eye also looks slightly larger than the other. I started looking at everyone's eyes with a penlight up close and personal and discovered that Valkyrie has the same thing, too. Both of these does were produced by Kari in different litters years ago.

Upon researching (because I have nothing if not time right now), this appears to be a hereditary form of glaucoma, which is apparently very common in domestic rabbits. I had never seen or heard of it before though, so I had to start digging through some books.

What I have found is that this disease causes deterioration in the eye and can go unnoticed for a long time because the damage is from the pressures inside the eye, not anything apparent to someone on the outside without special equipment. Slatter's Fundamentals of Veterinary Ophthalmology states that "medical treatment is ineffective" for rabbits with it. Apparently there have been genes identified in some New Zealand and Chinchilla lines in particular (bu gene), but it has cropped up in many other breeds. The age of onset is extremely variable. Rapid Review of Exotic Animal Medicine and Husbandry states that 1 in 4 of offspring from animals with the genetics for this may eventually show symptoms, though sometimes none do as the genes are not simply recessive. It also says that glaucoma in rabbits is not typically associated with pain like it is in other animals, and that by the time it is noticed clinically that the animal usually already blind in the effected eye(s). 

It is very unfortunate that 3 of my brood does are showing this problem and I'm not sure what to do from here other than try to keep moving forward. I wouldn't have bred them had it been evident to me that there might be a genetic link, but what's done is done. I will be watching their offspring very closely for any eye anomalies, but I just wanted to share the latest in case it is helpful at some point to anyone else.