I think before we justify breeding every cycle based on science, we must remember that our dogs are not in a natural setting. They are our pets first and foremost. In a natural setting, just a few puppies would survive, not all. If they were coming fast some may not even get out of the sac and then some may weaken and die because other pushed them out, the bitch might lay on other, etc. I also don't think some bitches care as well for the babies on a back to back breeding. Further reducing numbers in the wild.
While the science tells us one part of the equation, there are other factors to consider when choosing to breed a bitch. It's important to know about both the science and the practical realities. I recently bred a bitch back to back. The first litter was one and the second was eleven. I wouldn't even dream about breeding her on her next heat. Sandie Hawkins Sajan (Berners since 1975)
