Do you have to wait til they are fully feathered, like chicks, to put them outside without a heatlamp? My Black Swedish and Pekin are getting big quick. I would love to get them out of their brooder, but they are only 2 and 3 weeks old. Not sure if they would be too cold at night yet. Unless I could put them into an outside run during the day when its sunny and bring them in at night?