At least 2 of my chickens have dry skin. I have 4 ex bats-about 19 months old. I have checked their feathers and there is no sign of mites or lice ect.... I haven't had any 'symptoms' as such of mites or lice myself and I handle them a fair bit. There is just lots of dry flaky skin! I also never see them scratching themselves, just occasionally preening or shaking feathers if wet! Is this something to be concerned about?