If it is canker, it is contagious to others. It is carried by pigeons and other wild birds. But canker is supposed to have a rotten odor. Occasionally chickens will have white or yellow material in the beak from a fungal infection (yeast or candida,) the wet version of fowl pox, and due to bacterial respiratory diseases which are more in the throat and airway. The best way to get a diagnosis is for a vet to look at the organism under a microscope or to get a necropsy after death.
In addition toAqua Zole, canker is treated with acidified copper sulfate 1/4 tsp per gallon of water. You can get it online here and elsewhere:
https://www.strombergschickens.com/product/acidified-copper-sulfate-1-lb
In addition toAqua Zole, canker is treated with acidified copper sulfate 1/4 tsp per gallon of water. You can get it online here and elsewhere:
https://www.strombergschickens.com/product/acidified-copper-sulfate-1-lb