Canker presents itself as necrotic looking lesions inside the mouth and I didnt see any dark in color lesions in the photo. It's not Coryza, there are no other symptoms present, besides, other birds would show symptoms as well, it's the same with MG. Cancer could be an issue, but I'm not sure. You can try Metronidazole if you wish. Treatment is for 5-7 days and you should notice some improvement within 5 days.
Fosbac is an antibiotic and it wont treat canker since it's a protozoal infection. Fosbac would treat MG, and Coryza along with a sulfa drug.
Fosbac is an antibiotic and it wont treat canker since it's a protozoal infection. Fosbac would treat MG, and Coryza along with a sulfa drug.