Could it be fowl pox? If it's hard like that it sounds like pox. You can take that "core" (yellow stuff) out and make sure he can see to eat and he should be fine if it's pox
You have to do it every day though. In my experience, as long as it is dry pox and not wet(even though they can get...
Report to the Mods! That's a cop out! I get offended every day I leave my house with the things I see and hear. Am I going to call the police because I am "offended"? Please!! Get a life!