Scaly face is a mite infestation of the beak. It shows up as a yellow crust at the base of the beak. It can go unnoticed for some time, especially if it starts under the beak.
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Swollen feet can be caused by the same type of mite._x000D_
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Many breeders have reportedly achieved good results by smearing the beak/feet with vaseline or a similar product. Vets will usually suggest a more aggressive treatment._x000D_
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I am not a vet. Ask a vet before starting any medical treatment of your birds._x000D_