line breeding your dog what would happed to the pupply?

I have bred a buck rabbit back to his daughters, his grand daughters and so on for 7 years. Because he had such a great bloodline with no defects, he produced beautiful bunnies. Dogs are another story. You should only breed a dog no more then once a year, and you might only have 1-9 puppies to choose from. You really have to watch the temperament of the puppies. With rabbits, you eat your mistakes so the bloodline improves rapidly. With puppies, defected puppies are saved by going to the vet, and in time, this genetic defects will be passed on to their offspring. Think of bad hips in labs.All of the different breeds of dogs today were started by breeding closely related dogs together in the past. Unless you know the genetic background of your dogs, and what if any defects are present, I would not breed too closely related dogs together.