I have 5 3 week old layers, 4 3 month meaties, and 2 1 year layers. I have just found out all have lice. I also have 2 children under 3. All my chickens run free around my lawn. How do I go about treating them? I am in Ottawa Canada and the coop says I can not purchase any poweder as i need a pesticide license... does any one have any reccomendations?