Question-Re Identifying Disease

Question
Hello,
Our first Rabbit just passed away two days ago, causing us much sadness and grief.
In order to make sure that the death of any rabbit is not my fault, i'd like to take upon myself to better understand how to spot signs and symptoms of Rabbit disease.
I'd like to describe to you what happened to our Rabbit; perhaps you can shed light on what was going wrong with his health?

I went away on a business trip and left our Rabbit to the care of my family. Upon return from my trip, i noticed that the Rabbit wold nervously jump and twitch in the cage, as if something was really bothering him. I checked his fur and didn't find any marks, sores, fleas, etc.
The Rabbit played nicely, ate, drank, but continued to twitch like this for a month.

Three nights ago i let him out of the cage to roam around the house and he seemed fine. In the morning, he seemed tired and weak. He was lying down as if he had no strength. He was breathing with eyes open. I gave him some hay and strips of red pepper, which he ate.
A half hour later he looked even weaker than before, and i knew something was really wrong. My mother took the rabbit outside to put him on the grass and see if he would appreciate going outside. Meanwhile i scrambled to find a vet. Sadly, our Rabbit died in my mother's arms, and is no more.

I feel tremendous guilt that perhaps i could have been better educated and prevented this. Can you shed light on what may have happened to my Rabbit?
Abe-

Answer
Hi Avi

So sorry to hear you lost your bun!

The twitching and jumping sounds a lot like binkies, when they jump, shake their head and flick their feet out of happiness. Rabbits can have seizures, but the action you describe sounds more like binkies!

As for his sad passing, there are so many things that could have happened that I'm afraid I can only hazard vague guesses. He was eating and it wasn't a sudden collapse but it could still have been his heart or organ failure. If the twitching you describe was continuous and not binkies, it could have been something neurological, including a neurological parasite called Encephalitozoon cuniculi (or EC).

Sorry to hear your bun is gone, they can be very delicate creatures but are so good at hiding pain and sickness.

Hope I helped a little :(
Cat