Is there a good book or web site that will help me understand if its possible and how to maintain decent genetic diversity in a small flock of chickens? Line breeding, spiral breeding, out breeding, inbreeding… Is it possible to maintain a closed flock with only a couple roosters and a dozen hens for more than a few years? It would be nice to not have to buy outside stock all the time to keep my birds healthy and productive. Hopefully there are some good books on raising chickens out there that wont hurt my head too bad. What do you recommend?