This threadbrings up a lot of questions. I think we really need more specific info on what exactly was done at the vet's office. Some things here don't add up so I have more questions than answers. My first question is the use of Baytril....and a couple of points there. First, the tablets taste terrible....they are liver flavored. While very few rabbit savvy vets use Baytril now, when we did, we flavored the infusion version for oral use....but Baytril seems to work better if injected. If we are going after a confirmed bacterial infection, there are much better choices available as far as antibiotics. I would also have to bring into question why we would use an antibiotic if we had a low body temp as most bacterial infections will raise the body temperature. Did the vet administer fluids either sub-q or IV? That is basic response to kidney issues....even entry level techs know that. Did we do x-rays of the abdomen looking for GI or bladder issues? Low body temp is nearly always a sign of shock....and GI stasis will lower the body temp and lead to shock. Shock should be considered an emergency in any species and treated accordingly....quickly and aggressively.
Based on the post....and I will officially reserve judgement until we hear more from Toby....at this point I must question the care from the vet. Maybe Toby can enlighten us on more facts so that we can help him out here. I am hoping that much more was done to treat this rabbit than the posts indicate. And just a note about using Critical Care with a dehydrated animal.....hydration before nutrition. If you put food in a dehydrated GI, the body will be forced to pull fluids from the rest of the body in a losing attempt to digest that foodand this becomes a self feeding problem as the animal cascades deeper into dehydration. And Critical Care requires a lot of fluids to both mix and digest. In an emergency situation....always get hydration before nutrition.
And kidney problems are no more common in rabbits than any other species. Some are prone to bladder sludge. That has been blamed on improper diet....specifically high amounts of calcium....but the jury is still out on that as it seems that might be more of a herditary issue....just like some humans (me) are prone to kidney stones no matter what. Dental issue can cause issues like this. Infections or tumors in the abdomen. And EC is always lurking to cause havoc in the renal system.
I have a feeling this might be a GI problem as much as anything. In you reply post Toby....if you could give us a run down of your rabbit's complete diet as well as water intake. Also consider the possibility that he might have eaten something that would cause a gut problem....certain beddings are always suspect and carpet fibers must usually be considered. I think we might need to be expanding our look at this issue in order to help you and your rabbit.
It would also be of help if you could post your general location in your profile as we all have rabbit savvy vets we can refer you to if necessary.
And just for information....we have had rabbits in renal failure (for various ailments) for years.....our Yoda was in renal failure for nearly two years secondary to EC and our modified husbandry protocols gave him a good quality of life for that period of time. It's all in understanding and correctly diagnosing what is going on.
Looking forward to seeing more info on this situation....and hopefully offering you some good advice.
Randy