The thing Robby will usually qualify that with, is the fastest way to close a line off genetically is to select for only egg color. You have to be careful you dont end up with terrible birds that happen to all lay the same color eggs. When you select for egg color alone you are pretty much only hatching the eggs of a few already related hens and typically you are pairing them with a rooster that hatched from the same color egg (sp also related). Outcrossing will be necessary to keep stock verile.
