rabbit-urination

Question
Our Pre-K pet rabbit has been peeing often and a greater amount than usual.  Sometimes the pee is clear, sometimes yellow/orange.  The vet here in Cairo said he was in heat and gave him a shot of something and said that the symptoms would lessen, which they haven't. He also talked about castrating the rabbit because of these symptoms.  I don't want to do that.  What else could be causing this?
Thanks.

Answer
Dear Mimi,

Excessive drinking accompanied by excessive urination of very dilute, pale urine can be a sign of renal disease.  This can be checked by a vet with a blood sample tested for B.U.N. and creatinine, as well as a few other electrolytes that can indicate kidney function.  It is best to pair this blood test with a test of the urine's specific gravity, which will tell the vet whether or not the bunny is concentrating his urine normally.

Spay/neuter is highly recommended for the rabbit's health and longevity, as you can read here:

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

but only if you have a vet who is experienced and good with this procedure in rabbits.  You can read more here:

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

I don't think the urinary problems are related to the bunny's sex.  Rabbits don't "go into heat."  They are induced ovulators, and almost always sexually receptive.  When they mate, they ovulate.  They have minor cycles of greater or lesser receptivity (on the order of 2-3 days!), but that's about it.  They don't have estrus cycles the way most other mammals do.

I hope this helps. Please write back if you have any other questions.

Dana