Karen is right about the clay kitty litter being very bad for rabbits.

What I'm surprise that I haven't seen anyone mention is that Pine and Cedar shaving are also very bad..Recent studies have shown that the rabbits urine when combined with either type of shavings eventually causes liver cancer. It's something to do with the chemicals in the soft wood used to make the litter.

Please stop using pine/cedar shavings immediately.

See the House Rabbit Society web page, either under litter training or health www.rabbit.og.