Something to consider--if you are going to put them outside in your brooder house, with heat lamp, when they aren't but 3 or so weeks old. Make sure they can't get gotten at by rats, if there is any chance you have some there. My sis-in-law, a few years ago, got 50 baby chicks and put them in a cardboard circle with heat lamp, in their outdoor chicken house. Couple nights later, rats got in there and killed all but one. Good Luck.