Studies have shown that root vegetables, including carrots, are not good for rabbits. Instead, the owners must feed their pets on hay and grass.

The charity said that only 8 per cent of owners knew what to feed their bunnies, while the remaining used carrots and other salad foodstuffs in their pet’s staple meals.
According to research carried out at the University of Bristol commissioned by RSPCA, eleven per cent of pet rabbits suffer from tooth decay while another eleven per cent develop digestive problems.
Rachel Roxburgh, an animal scientist for RSPCA says "Bugs Bunny was wrong." "We want all pet rabbits to be eating hay as their main food. People also think their rabbits should eat carrots because that's what Bugs Bunny does." But he's a cartoon, real rabbits don't talk, and they shouldn't be eating carrots too often either."
In the wild, rabbits do not naturally feed on root vegetables, fruits, cereals or and iceberg lettuce. Some of these foods can prove to be dangerous. Carrots and apples have very high sugar content and therefore, must be given to the rabbits as occasional treat only.
Hay and grass are best for rabbits, according to RSPCA. The charity recommends providing the rabbits daily with good quality hay in bundles that are approximately the size of the rabbit. They must not be allowed to graze on lawn clippings but must be encouraged to feed on growing grass.
The charity has launched a campaign called “Hay Fever” to teach owners to feed rabbits correctly.