Thank you. The tripe antibiotic cream shouldn’t hurt the mom if licked?If it's getting soiled, yes, clean out the soiled and replace with clean bedding. Otherwise, when the babies eyes open it will start wandering out of the nest. When it won't stay in the nest any longer, the nest box can be cleaned out and placed on it's side as a little cubby hole for the baby to have somewhere to still snuggle up in.
Normal baby bunny poop is really tiny, like a speck at this point. So might be difficult to even notice. Unless it's all coming out mushy, then the mom may just be licking it off when she stimulates the baby to pee(if she's doing that like she should be), except when it's drying out stuck on there like you've already encountered.
If the baby had an open wound at the anal opening, that dark dot you are seeing may not be poop but is a scab. If this is the case where there's a wound, I would put a thin layer of plain triple antibiotic ointment(not the one with added pain relief) on the sore and anal opening, at least a couple of times a day, to help keep it moisturized and aid in healing.
Thanks. We’ll keep an eye on it and swap out if need be.If' it's actually trying to ingest the cardboard, yes that could be a problem, regardless of whether it's a paper print or smooth printed cardboard(added plastics I believe, makes it more of a risk if ingested). A little bit of paper(not smooth printed) cardboard ingested by adults usually isn't an issue, but excessive ingestion or ingestion of large chunks can pose a gut blockage risk, as cardboard doesn't break down in the digestive tract. And with this baby being tiny and new to ingesting solid food, ingesting cardboard would seem an even greater risk to me. It should be nibbling on grass hay as it's first food and for roughage/fiber. If it won't leave the box alone, either try a different box(maybe that one tastes good for some reason) or use a plastic bin or wood box.