I've been waiting on my coop. I've had my 4-5 week old pullets in my brooder. I'm new to this, but I knew that it was alilltle over crowded. I was in out of my shop all morning, but within minutes, the pullets started pecking on two of the smaller ones. When I got to them, they were bleeding pretty good. I got them out and put them in a seperate cage. I think if I wouldn't have come in when I did, they would have killed them. Boy, did I learn a lesson!!!! NO OVERCROWDING!!!