Rabbit Glaucoma: Recessive Gene (both parents must carry)

I have a 4-month-old Flemish Giant sandy buck who the other week had first a cloudy eye and then a rapidly distending eye. I knew this was beyond my farm store remedies and raced him over to emergency at my very good rabbit vets. By the time we arrived, the eye is hugely distended and entirely blue, not brown, with no visible iris or pupil. The blue was from fluid that gets trapped in the interstitial areas of the cornea and then reflects the room light. Normal pressure for a rabbit is 10-20; this buck's pressure was 51 in that eye. The vet indicated that the eye would not have exploded, as i had feared, but that the rear wall could have given way, leaking fluids into the skull.

The vet on duty was not one of their rabbit specialists but an incredibly bright and motivated vet who did what research he could on available US vet databases. He was utterly shocked to find glaucoma in a rabbit this age, kept him over night to get the swelling provisionally under control, and advised me to find a vet opthalmologist who saw rabbits who would have better equipment and knowledge. I ended up with a wonderful vet trained in the UK and recently returned here. She has access to UK/Europe databases and apparently rabbit glaucoma is more prevalent in Europe and thus known to vets.

Rabbit glaucoma is a recessive gene, meaning both parents must be carriers; with both parents as carriers there is a 12% chance that a kit will receive recessives from both sides and manifest the glaucoma. Rabbit glaucoma differs from cat or human glaucoma in that, provided the animal remains in relative comfort, there is a good likelihood that the tear duct causing the glaucoma will "sort itself out." No one has studied the average time on this that my vet knows of, but it seems to occur within a window of maybe a few months to a year. The eye by then is largely useless but generally does not require removal. The important thing is that this animal should not be bred -- it is not merely a rabbit that went blind in one or both eyes. So long as the manifesting rabbit is not bred and carriers are not bred to carriers, the recessive will eventually drop out.

As I understand from a few breeders, glaucoma is becoming more common in US breedstock than vets in the US realize. The signal problem seems to be that since it is still so relatively rare, many people do not realize that a rabbit that has gone blind in one or both eyes may have done so due to a recessive gene. If the animal has good type/fur, they may unwittingly use the rabbit as breed stock despite its not being showable. This is a very bad idea and can really create havoc in a breeder's line.

Just wanted to alert people to the possible issue. I hope this is useful.

I'm so sorry this happened to your little guy. I hope the breeder has been notified & won't be breeding the parents again, at the very least not to each other.

Yes, it was a new breeder who inadvertently had two brothers -- back a couple generations in the pedigree, one on either side. Given some other shared characteristics, it's pretty clear these littermates were the recessive carriers. Everyone who has relevant stock/offspring has been notified about this, about what lineage not to breed with what lineage and I believe on selling any offspring will pass on the possibility to buyers-- they are all very honorable folk. Hopefully that will just drop out soon. I just wish there were more generations on a pedigree so people could be sure. Some recessives can take a long time to resurface. The more history you have, the better.

My little boy is doing great now that we have an adequate regimen to keep it under control, which was difficult. Little guy is just hilarious hell on wheels. During playtime Friday night he went from the piano bench to keyboard and then ran up and down the keyboard delighted with his new power to make noise. I, of course, was horrified, because he should not be up so high. Fortunately, I got him down safely and have moved the piano bench. He is in an extra-large dog crate with the door opening out onto a small area bounded by a 3.5 ft high dog pen. At midnight I awoke to a clatter. He had climbed the dog pen and had half of his body on either side, contemplating how to get down and out. So I had to take away the dog pen, which he wasn't too happy about. But I'd say he's doing darn well now. He probably will lose sight in that eye and can't be bred or shown, but he is the grandson of my most beloved rabbit ever and his personality is so much like his grandfather's, that's all that matters. I love him to death. Thanks for your concern.

as far as the dog pen goes, you can take poster board or cardboard or something and zip-tie it around the top so that he can't climb all the way up and get over. that was the suggestion given to me when my lionhead suddenly learned how to climb out of a 48'' pen and it has worked wonderfully. here's how it looked when I put the first piece up (used foam board for that and just did the corner I caught her climbing because I hadn't gotten to the store for poster board yet):

Great idea-- Thanks.