Dan - Thank you for the post. The thread about breeding two males to one bitch & DNa varification has got me thing about how one could use modern science to "brred-out" (or greatly reduce)genetic health problems in thier breed of choice. In my case Rottweilers aren't know to live past 10yrs. They don't really mature until 3-4 years. erious health issues don't "usually" manifest until the dog is 6+ yrs. That said if Sperm from 3-4 yr. old males that had correct conformation, disreed working ablity and proper temperment were frozen an not used until the dog had reached maturity, one could evalute the stud true contribution to the gene pool. I'm sure the people that own the famous race horse "John Henry" had wished they had frozen a few straws. :wink: Of course this only accounts for 1/2 of the Genetic meassage. So, eggs would also have to be saved so the bitch could also be evaulated.