I have a male Peking that is about 4 years old. He bill is almost entirely black. I give him peas weekly, with red palm oil.
He has access to a large run with grass etc. I give them scraps of veggies etc.
He seems perfectly normal. Feet are normal. I give them red palm oil based on a recommendation from a vet who told me it helps with their immune system. I am going to start giving them more corn and kale.