I was reading that a woman uses Advantage Flea control for cats on her chickens to kill mites and internal parasites. She mentioned it costs her about $250 to treat her flock. Why she doesn't use poultry powder or DE or any other poultry de-wormer I have no idea. She still sells the eggs as organic She said the Vet told her it wouldn't harm the eggs. I wouldn't eat them. Has anybody heard of this practice before? any thoughts?