Although the page on ‘good and bad reasons to breed’ covers much of this subject, there is a lot more to it than that. If you do not yet have your foundation bitch and are about to begin your search, you should start with researching the families of bitches under consideration.
The first thing that will probably attract you is the general ‘type’ that certain lines and families produce. Once you’ve decided on this, start asking questions about what health and temperament evaluations the dogs in the pedigrees have had. It’s unlikely that you’ll be able to trace these traits for every dog, but at least try to get an idea. It isn’t too much to expect that the dogs for the last 2 or 3 generations (hopefully more) have at least had their hips evaluated for hip dysplasia. Ask to see the OFA certificates or letters from the veterinarian who did the evaluation. Most countries where the dog or bitch come from perform these evaluations with a few exceptions.
It’s true that many breeders hesitate to sell their best puppies to a novice. This is why it’s a good idea to attend shows, meet the breeders and try to find someone who will act as your mentor as you learn about Great Danes.
Before you take the first steps to breeding a bitch, it’s a good idea to have at least a working knowledge of genetics.