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Question
Dear Dana,
For nearly the past year, I have been taking care of two mini Rex rabbits for a friend who could no longer care for them.  Last week, one of the rabbits appeared to loose functioning in her rear legs.  I took her to my normal vet immediately, who stated that he thought she had a broken or injured back, gave her a steroid shot, and seven day follow-up medication.  My friend, who I also notified immediately, began researching on the internet, and became increasingly convinced that it was a parasite (E. Cunniculi?).  She contacted a bunny expert in her area, and then contacted my vet and we arranged to pick up a dose of anti-parasite medication.  My friend was under the impression that the medication should have been several doeses, though my vet only gave us one dose, and said that if the rabbit showed improvement, she could have another in two weeks.  I gave her the anti-parasite, and continued the medication my vet had originally prescribed for the full seven days of its prescription.  Throughout, the bunny showed no signs of improvement, though, since she did not evidence any pain, and continued to eat and drink, as well as eliminate waste normally, I did not take her back to the vet to have her euthanized.  My friend, the rabbits' technical "owner" had stated that if the rabbit did not have any improvement by this weekend, she would take her in to be euthanized, as it didn't seem like much of a quality of life.  (I should mention, that neither blood work nor x-ray were done to diagnose the rabbit, as both of the treatments were deemed to be relatively benign if the diagnosis was incorrect.)

Yesterday was the eighth day.  When I arrived home from work, I was alerted to the ailing rabbit's decline.  Her breathing was slow, she was non-responsive and leaning over.  Within ten minutes, she was laying down.  Within two-to-three minutes of that, she expelled a large (egg-sized)"ball" of "mushy" (not runny, but not regular consistency)feces, and stopped breathing.

I am writing, knowing that it is too late to change anything, but trying to understand what may have happened.  Additionally, since there is another rabbit, I'd like to have some insight in case the other rabbit starts showing symptoms.  (The rabbits were caged separately, having different eating and drinking apperati, and have not had any direct contact for weeks.  We disposed of the cage that the ill bunny was in, as well as all of her utensils.)

Do you have any information that can help us make sense of this, or prevent anything similar happening?

Also, what I consider to be a rather strange thing happened.  When the bunny died, her tail came off.  Does that mean anything?

Thank you very much for your time.
Sincerely,
VW

Answer
Dear Vron,

I'm sorry about the loss of your bunny.

The vet who administered the Panacur (fenbendazole) or whatever was used (I hope it was not albendazole, which has been linked to acute toxic death in rabbits) was obviously not familiar with the protocol for using the benzamidazoles for treatment of E. cuniculi.  Giving the drug once a week or so is fine for worms, but would be ineffective against E. cuniculi.  Here is the original article on which the treatment protocol is based:

www.bio.miami.edu/hare/fenbendazole.pdf

It's very weird that the bunny's tail came off when she died.  It makes me wonder if she *did* suffer some trauma to the spine that also broke her tail, causing it to necrotize and fall off at the end.  Without radiographs, it's not possible to know for sure.  Only a necropsy would give clues as to the actual cause of death.

The other rabbit is not very likely to be at risk of the same thing.  But be on the lookout for early signs of illness:

www.bio.miami.edu/hare/sickbun.html

anyway.  It's always a good idea.

You can find a more experienced rabbit vet here:

www.rabbit.org/vets

And for all the best information on care, diet, litterbox training, spay/neuter, etc. for your surviving bunny, please visit:

www.rabbit.org

if you need one in the future.

I am sorry for your loss.

Dana