Excessive Drinking and Urinating

Question
Hi, I hoping you may be able to help us.  My two year old spayed female dwarf lop seems to be drinking excessive amounts and as a result urinates too much too!  She can get through about 800mls in 24hours, although somedays she will drink "normal" amounts too.  

She has lived with us for 6 months and has always had a higher water intake than my other rabbits, but is completely normal in her behaviour, eating and general self. She has recently been bonded with a male bun and during that process, her drinking again went to normal - now they are settled though, she is back to taking 500mls overnight. I thought it could be boredom, but I would class her environment as pretty good!

The vets have tested the urine and ruled out a UTI and also said the pH is correct.  We are now trying a course of Panacur to rule out an EC derived problem.  The vet mentioned he would now normally do a Water Deprivation Test on cats/dogs to test for the kidneys concentrating urine - but he doesn't know if this is done on rabbits or not?

What can you suggest may be our next step in solving the mystery?

Answer
Dear Kerry,

I would suggest you find a vet who is more experienced with rabbit medicine and ask for complete blood chemistry to determine her renal function.  You can find a vet here:

www.rabbit.org/vets

The bunny's creatine, B.U.N. (blood urea nitrogen) and other levels will tell the vet whether the kidneys are concentrating urine.  There's no need to do a water deprivation test, which could stress the kidneys further.

Polyuria/polydypsia (excessive urination and drinking) can be a sign of renal disease.  If the bunny is acting normal now, I would not interfere by giving subQ fluid therapy, as this can really throw things out of whack.  Rabbits with minor renal insult seem very well able to manage their own water intake and stay reasonably healthy.  Only if you start to see inappetence, lethargy or neurological signs is it time to consult the vet about intervening with subQ fluid therapy to help her flush toxins (if her kidneys can't do it for her).

Bloodwork in conjunction with a urine specific gravity test will help your vet determine renal function, and what, if anything, should be done.

I hope this helps.

Dana