as the "goldendoodle" and similar "breeds" show; the thin genes purebreeds have a use: parent stock to produce predictable, vigorous hybrids.<p>We had a kennel for a while; we did several litters of Great Dane / Collie (our keepers lived to ages of 12 and 16, and were healthy throughout). Then we switched to Bluetick Coonhound / Catahoula, and still have several of those (<i>impossible</i> to fence in).<p>Look at the grain that the world eats: it's <i>almost all</i> hybrids. The seed corn / soybean farms are a sight.