I have a chicken who has been laying eggs & acting normal. She has been losing feathers & I would catch her eating them. Thought maybe it was a lack of protein. Began supplementing with eggs, mealworms, & tuna. Found her dead in the coop this afternoon. All other chickens are fine. No mites or lice in coop.... any thoughts as to what could have caused her death? This is my first chicken death.. I want to make sure I protect my other chickens... any thoughts would be great.