I agree that breeders should take back their dogs, I make it a stipulation that I am first to know if a dog is in need of a new home for any reason.
I have also taken in dogs from other breeders - some have not wanted to help - some have, but one thing I always do is contact the breeder myself to make sure they KNOW about the situation,, it has happened that the breeder was not told. This even if someone said they had been contacted.
I always contact each of my puppy owners when a dog that could fit an age and area of one of mine is talked about. This to make sure mine are all safe. (once one of mine that I had given to a home was in the pound, they people even handed inthe papers showing my phone # I must say I was furious, and also thankful that another breeder found out and contacted me. I got the dog and she was safe.)
Yes I have lost contact with a few over the years, but not for lack of trying to keep in touch!