Loss of our rabbit

Question
My fiance and I recently lost our 3 year old lop eared rabbit, Leo, on Tuesday. On Monday evening, Leo seemed absolutely fine. He was playing and being his normal self, playing peek-a-boo w/ his blankie and everything was great. His stool and urine were normal, as well as his appetite. We went to bed, and on Tuesday morning, my fiance found Leo laying outside his litter box on his blankie in a bunch of diarrhea. He had raspy breathing, nasal discharge and was not moving. Raymond (my fiance) picked him up to clean him off, and Leo was nonresponsive (but still alive). He was not resisting at all. Raymond rushed him to the vet, and his gums were very blue and his body temp low (98*). The vet was thinking pneumonia. She did a fecal, which was normal. She then placed him in an incubator, and within an hour, he passed. We had him necropsied, and no gross lesions were found. His lungs were also unremarkable. The histopath results are still pending.

Leo was treated for fleas (w/ Advantage) 4 weeks ago, and we also flea bombed our house (in which he was removed for 24 hours of course). Upon putting on the topical treatment, Leo had a skin reaction almost immediately. His skin turned pink, then red, then more red, then started to blister and bleed. We wiped it off immediately, and watched him very closely. He was acting normally, and nothing else happened. The rash went away and he was fine. Well, the vet is thinking that the cause of death is related to the flea treatment, and to the flea bomb that we did that weekend...but that was 4 weeks ago... How could something be toxic to him, but nothing happened for 4 weeks? Is there anything else that could have caused his death? From what we could tell, he didn't get into anything, chew on any cords, etc. I would think that if it was the flea treatment that did it, that something would have happened before now. We're just frustrated that we don't have a definite answer, and we may never get that. The pathologist decided NOT to do a bacterial culture b/c no gross lesions were found. And my first guess was that it was something bacterial. I know that bunnies can get stressed very easily and succumb to illnesses b/c of that. The flea bomb may have been stressful on him (as well as the new dog we got that initially HAD the fleas). We are just so shocked at his sudden death, and we feel like we did something wrong. We really miss him...and I hope it wasn't something we did wrong. We did everything the vet told us to do as far as flea treatment goes. Any thoughts?

Answer
Dear Leslie,

I am so sorry about this sudden, traumatic loss of your friend.  And yes, the cause will probably remain something of a mystery.  I'm glad the vet sent tissue samples off for histopathology, because it is sometimes possible to see problems on the microscopic level that are not evident on gross examination.

The watery diarrhea is a sign of cecal dysbiosis:

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

which is often associated with illness/pain/stress, and can progress to full-blown ileus if not addressed.  But if he was acting normal the night before, I can't imagine that he was in full-blown ileus:

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

The flea treatments are suspicious.  I've never heard of a rabbit reacting to Advantage that way, but the combination of stress from the dog, any residue from the flea bomb, and the weird, idiosyncratic reaction to the Advantage might all have contributed to the bunny's passing.  I hope the histopath will reveal more, and give you some closure and peace of mind.

Please don't blame yourself, though.  No one could have foreseen this.  I know plenty of people who have used Advantage and flea bombs, and their rabbits are fine.

As you say, the exact cause of death might never be known.  That sometimes happens, and is horribly frustrating.  But I hope you can take some small comfort in knowing that even if Leo's life was too short, it was filled with love and care.  That's something most rabbits never get.  Leo was loved, and will always be part of you.

I hope this helps in some small way.

Take care,
Dana