Hi!

This could perhaps be from having a wet chin after drinking. Skin that’s constantly wet loses some of it’s barrier function and yeast and bacteria can then colonize the area. The fur becomes tangled and discolored, eventually it falls out, leaving bare, raw skin.

How do his incisor teeth look? Rabbits are normally good at drinking from bowls, except if they’re very fat (big dewlap) or arthritic. Your bun doesnt look fat and he’s too young to have bad joint problems.

There are cat bowls that are lower in one end, and there are bottles (which many buns need some time to get used to, so don’t make an abrupt switch to just a bottle). But it is of course important to figure out why his chin is wet all the time (if that indeed is his problem).

Another possibility for scabbing around the mouth/nose is rabbit syphilis. It’s not the same as human syphilis and you can’t catch it from him. The rabbit often gets it from his mom and it can lie dormant. The scabs are typically closer to the mouth/nose mucosa though. Treatment is penicillin injections (penicillin must only ever be given as injections to buns) and it needs vet treatment, it won’t heal on its own.

Hmm… I agree, it could be a number of things, especially since there is limited information. It could be dermatitis caused from a water bowl or a dental problem. Or it could be an infection like syphilis.