We are new to the BYC Forum and need some help... We began raising chickens about a year and a half ago and things have been great! However, recently our girls have lightened up on laying and are losing feathers on their behinds, back of necks and on the joint of their wings. I have looked for mites, lice, larvae and the like (do I need a magnifying glass) but haven't seen any trace of them. The girls are still eating and drinking well, but I am concerned. Any ideas, tips, etc?