I don’t see anything alarming. Sometimes a lot of white chaulky material on combs and the face can be favus, a fungal infection. But in winter, during molting, and when they are not laying, dry flaky skin can be normal. You could try some coconut oil on the combs to see if it helps, or if you feel that it is favus, miconozole or clotrimazole are antifungal creams that can be applied daily.