I've been using DE since about 2 weeks into chicken owning. The best thing I have ever bought!!! I too sprinkle it in the coop, the run, and extra under the roosting bars. Supposedly it sucks moisture out of just about anything, including poo, which repels the flies from laying eggs in a too dry environment. The chicken poo in my coop is pretty nearly always dry also eliminating the odor considerably. I've heard about DE possibly getting in their lungs, but mine are out all day, and only in the coop at night. I've had only great results with it.