I would not feed any puppy food; Even large breed puppy food is not safe. It is all a huge conspiracy; Babies need baby food, so of course pet food companies came up with a huge marketing scam for puppies. Pups in the wild do not recieve alot of food after the pack is done regurgitating for them. They are on the bottom of the pack, and eat what little leftovers there are; Usually just stomach contents and scraps. They are meant to grow very slowly, and properly. Puppy foods are high in fat, calcium, and vitamins, causing the puppies to grow very fast. In large breeds this can cause growth issues -- in great danes you'll mostly notice it in the front legs.
I am a HUGE advocate of structure guru Pat Hastings. NO ONE has done the amount of research into structure that she has, and she is 100% against puppy foods. In her seminars she shows ALOT of pictures of great danes that she helped "cure" because if you stop puppy food soon enough you can help reverse the problem -- not entirely, but a very knuckled over great dane can improve. She also bred dobermans for many years. She holds seminars all over the world, and she has evaluated 30,000 litters -- many of them fed puppy food -- and she concludes that puppy food is one of the worst things you can do to your puppy, structurally.
I had a GSD puppy when I was a kid whose legs grew too fast for the rest of him; He had to be put to sleep when he was 6 months old because he could no longer walk. We were told it was because he was fed puppy food. He was extremely knuckled over and easty-westy in the front. His long bones were putting alot of pressure on his pasterns; He was in a great deal of pain.
All of my puppies are started on adult food now, and I make sure my puppy owners do the same. My lines are quick to mature and I want to make sure they grow properly.