What kind of mass was it? Was the vet able to take care of it?

Let him have his cardboard boxes — bunnies love tunnels to run through and places to hide.

Is your bunny neutered?

If they ingest a bit of cardboard, it’s ok. It is cellulose, i e a type of fiber.

My bunny Yohio had a tooth-trim the other day, he’d stopped eating and the vet felt a mass in his tummy. Nothing that felt cancerous or bad, she deemed it food. When they can’t eat hay like they should, they get tummy problems because their tummies rely on lots of coarse dietary fiber.

Anyway, I kept giving Yohio CC and simethicone, and he pooped out splatches/clots of not very nice very dark sticky poop. He also farted a lot when I gave him tummy massages, I could smell it. (At one time I could even hear it as I’ve written about in another thread.)

When the contents of their intestines doesn’t move through like it should, there can be overgrowth by gut bacteria that release gas, which is very uncomfy for the rabbit. Massages and exercise helps.

If the problem lies with his teeth, which is very likely, the problem should go away in a few days after a grind. But you should ask for some metacam to give him the first few days after if he exhibits pain, because they can be very sore and refuse food for that reason. I syringe-fed Critical Care (CC), but last night he started eating on his own, muching away like a house on fire, so it seems he’s a lot better now.

My Yohio is very alert and active this morning and slept in my bed during the night, which is normal-Yohio-behavior. He had the tooth-prodedure done on Tuesday.