Rabbits drinking lots of water

Question
Hi Dana,

I recently had my lovely bunnies neutered and they are doing
fine. I also, following the advice of my vet, found them some
new hay and changed their diet.

They absolutely love their new hay and can't get enough of it.
They are also drinking buckets of water. Way, way more than
before. Getting on towards 500ml in 24hrs between them. I am
starting to wonder what else might be in that hay! There is
indeed a quite reasonable chance that there may be some other
kind of herbal extract in the mix (if you get my drift!).

Are my rabbits stoned?! How would I know and would it have
bad side effects on their health?

Thank you for your opinion,

Sarah  

Answer
Dear Sarah,

Normal water intake for a mammal is about 90-100ml per kg per day.  So you may be able to gauge whether your bunnies' intake is normal if you can weigh them and then precisely measure their water intake.  Note that if they're using a sipper bottle, it might be leaking.  A heavy ceramic crock is better and more hygenic, as long as you wash it at *least* every other day with detergent and hot water.

I doubt anything in the hay is making them thirsty.  The hot temperatures most of the hemisphere is suffering could have something to do with their increased intake.  The rabbits should be able to internally monitor how much water they need, and I would not interfere with their water intake in any way.  They are not likely to drink themselves sick.  (Quite the opposite!)

Excessive drinking coupled with excessive urination of dilute urine could signal renal disease, so keep track of the urine.  If it's nice and dark, no problem.  But if it's watery, clear and copious, you might want to ask your vet about it.

I hope this helps.

Dana