No.
Vanilla is too concentrated and strong for a rabbit. You shouldn't give your bunny any oils, dried spices/herbs, extracts, flavourings, seasonings, or anything like that. It isn't natural or healthy for rabbits to eat or drink them, and it could lead to a bad health reaction.
Putting vanilla in the water won't help with the urine smell, anyway. The smell comes from two things (mainly): hormones in your rabbit's body, especially if your bunny isn't spayed or neutered; and ammonia, which starts to grow once it leaves the rabbit's body.
The only thing you can do to to help with the urine smell is to keep the rabbit's litter and habitat clean. Scoop out soiled litter every day, and scrub down all surfaces as needed (depends on your rabbit's behaviour - maybe as often as once a month, but at least once a year).
If your rabbit is dehydrated, or sick, that could make the smell worse. Look for other signs of ill health, and consider bringing your bunny to the vet.
See the related questions below for more info.
When there is no water in there body their urine turns dark yellow and starts to smell funny.
rabbits mark their scent by rubbing their chin on things. the odours from their urine and faeces also leave their smell on surfaces and materials etc. if you want to wash away their scent, you can use a water and white vinegar solution (small amount of vinegar to lots of water).
Water the yard, urine will dilute and dissipate into the soil.
There are many reasons why there could be a urine smell in the bathroom. If there is a warm air vent near the toilet, it is possible urine could have gotten into it. If your water comes from a well, the well may be picking up extra minerals. This can cause water in the toilet to smell like urine.
if you smell that you should change the water.This is just natarual when the water isn't changed
Wash the floor with a 50/50 mixture of vinegar & water. As the floor dries, the vinegar smell will dissipate along with the smell of urine.
Mix a cup of white vinegar and a cup of water, then pour directly on the urine stain, leave for about 10 to 30 minutes, then rinse out with cold water and take it out to dry. This should take care of the urine smell, well until next time.
Any excess vitamins that your body hasn't absorbed but that are water soluble leave your body in your urine.
Water, salt, no food colouring and the stale smell.
25 % white vinegar 75% water.
Soak it in a mixture of white vinegar and water.
yes you can by pooping with it to smell more like poo wow.... that is probably the worst answer ever.... but anyways please disregard the answer given by the idiot above me. but if you want to lessen the smell of urine, you have to drink more water. As you drink more, it lessens and dilutes the original smell of your urine. if All you have been drinking was water, when you urinate, there will be NO smell. as you drink and eat other things, it actually adds the ' smell' to your urine. :D