I am contemplating adding an annex to my existing coop for breeding purposes. I currently have 4 breeds (Lt Brahma, Australorps, SLW and BOs) in a communal coop. I will eventually have 10-12 hens of each breed with a purebred rooster for each breed. Of course, in a communal coop, the fertilization will be all mixed. My question is this... If I segregate one breed (hens and roo) in the annex, how long would I have to leave them in segregation before I could begin to collect eggs that would be purebred? Keep in mind that the day I put the hens in the annex, they could have been mated by a different breed rooster. In other words how long will it take for the hen to expel her "crossbred" eggs?