Hello all! I purchased two new serama hens about two months ago. Since day one they have chronically shaked their heads. They are active, strong appetites, breathing clear, nostrils and eyes clear, laying eggs and otherwise seem extremely healthy. I treated them with tetracycline just to rule out any URI. I also used diatomaceous earth as their dust bath for a week and a couple of days ago I tried some Sevin dust on them thinking it was mites. Nothing has seemed to help them at all. Any other suggestions? Thanks in advance!