I have been pulling smelly cheese-like boogers out of my 4 year old bantam modern game hen since December. Her nares will be clear for about 24 hours before they plug up again. It take about a week until her nose if fully clogged and I can pull the boogers out. I have been watching for sores in her mouth, and before today there weren't any. Today, she had white grainy bumps inside her beak on the sides of her tongue. I cleaned her nares and wiped her mouth and nares out with hydrogen peroxide before putting her back in the coop. She appears to be the only bird effected.
After doing some research, the only thing that seems to fit is "canker." I have no idea how she would have picked it up, but that doesn't matter now. She needs treatment. What do I use? How much? How do I give it to her? If I don't treat, will it kill her?