Sudden Death of Beloved Bunny

Question
Our bunny, a New Zealand white bunny, died this morning.  About 3 years ago, he had an episode of cunnuli? or whatever it is, with head tilt which we treated for quite a while, a month or so.  We used Baytril.  He had a permanent tilt to his right side, but recovered enough to hop around, eat, etc.  Recently, he had a weeping left eye which I really didn't think about.  It would come and go.  I thought it was from the hay.  We recently got a new kitten who was diagnosed recently with a parasite in her stool for which she was taking medicine for the last week.

Luckibunny liked the new kitty and actually seemed to be more active since she was around.  I saw Lucki this morning eating his hay, then he was dead about an hour later with some blood in the corner of his eye.

I assumed he had some sort of stroke, but in reading the internet blogs, it says strokes are not common in bunnies.  Could it be from his cunnuli episode 3 years ago?  The eye?  He was 8 years old.  It was just so sudden.  One other thing--there was some little poops around him his morning which I was a little shocked to see.  He usually is so neat and clean and uses his box regularly.

Any input would help.  I'd take him to the vet for an autopsy but we buried him right away.  

Thank you.

Answer
Dear Bunny Lover,

I am so very sorry about the loss of your beloved friend.  Unfortunately, as you probably know, there is no way to confidently establish a cause of death without a necropsy, preferably including histopathology of major organ tissues.

The blood in the corner of the eye is worrisome.  If you are in the UK, Europe or Australia, or in certain areas of northern California, VHD (Viral Hemorrhagic Disease) is endemic, and can cause relatively sudden death due to internal hemorrhage.  However, you usually will see *some* signs of illness before death.  

This also could have been a stroke, pulmonary embolism, or any number of cardiovascular catastrophes.

Another possibility, if the bunny and cat played together, is that the kitten gave the bunny a tiny scratch or bite in play.  As harmless as this sounds, it can be deadly to a rabbit.  Cat's mouths are full of deadly bacteria, and even a small bite or scratch can inoculate the bunny with Pasteurella and/or Bartonella, among others.  These can cause systemic toxemia within 12-24 hours, and unless a cat bite or scratch is treated aggressively with fluoroquinolone antibiotics (or possibly injectible penicillin), the infection can be horrific, sudden, and inexorable.

Again, with a systemic infection you'd expect to see *some* sign of distress, such as lethargy or inappetence.  So this leads me to lean more towards a cardiovascular explanation.  But there really is no way to know for sure.

I hope you can take some small comfort in knowing that even if his life was too short, he had a wonderful one with you, and he did not suffer a long, debilitating illness.  He was happy up to the end--which is more than most of us get.

I am so sorry for your loss, and send many healing thoughts.

Dana