Here are some articles that provide information on why it is so important to avoid speeding up growth rate of giant breed pups and what to watch out for regarding nutritional intake.

“Nutritional Risks to Large and Giant Breed Dogs: From Weaning to the Geriatric Years”
Susan D. Lauten, PhD
http://portais.ufg.br/uploads/66/ori...as_grandes.pdf

“Dietary Mineral Levels Affect Bone Development in Great Dane Pups”
Henry J. Baker DVM
http://www.bestfriendsvet.com/pdffil...vArticleWa.pdf

“Why Overgowing Your Large Breed Puppy is Dangerous”
Dr. Karen Becker DVM
http://healthypets.mercola.com/sites...eed-puppy.aspx