I have some 3 week old chicks that I have noticed have lice on them. They were hatched out in the coop, but taken to a brooder within 24 hours. I thought they probably came from the broody hen, but when I checked her, I didn't see any (doesn't mean they aren't there though I suppose). I'm wondering if she could have had them, and then when she started bathing more regularly, killed them off? Anyways, I am also wondering if Sevin is safe on the little guys, and if I should clean and treat my whole coop based on this?