Gramma, Rancher, and I think others here have mentioned their preventative and treatment for parasites. If you could rewrite your schedule and course I would appreciate it. I'm considering Ivermectin and other dewormers as well as preventative courses for my flock before winter strikes. I use DE and Lime in the coop bedding to control external parasites. If I put DE in their food does that prevent internal parasites? So much information and I'm trying to understand it all. My chickens do not have any symptoms.