Would a 4' x 4' x 3' pen be big enough for a trio of OEGBs? It would be a temporary breeding pen, they would be in there for a couple of months probably, just until I get a few purebred chicks hatched from them. They would also be out in a run ever so often, to stretch their wings a little. P.S. I could keep the rooster out most of the time, and he could run with the other chickens in the main coop. If he was in there for a few days every couple of days, wouldn't that be enough for the hens to lay fertilized eggs?