I purchased some metrodinazole from a local tropical fish store, and put some in my chicken's water. 250 mg per gallon of water. They have been drinking this for a few days, and my chicken that has the canker has showed a lot of improvement. The lump on her face has gone down significantly. My other chickens are also drinking this, which has anti-parasitic qualities, therefore my other chickens will (hopefully) be clear of the canker. Hope your chicken will improve!