Vitamin C is a great supplement for your growing puppy and adult dogs.
I use human grade
supplements on my dogs (I purchase the Kirkland Vitamin C from Costco or powdered Nutricost Vitamin C on Amazon). Starting at 5 weeks of age I give 500mg every other day until 12 to 14 weeks. Then 500mg once a day until 6 to 8 months of age. After 6 or 8 months
I increase puppies to their daily dose of 1000mg once a day for life.
Vitamin C is used to help with cartilage build up, proper joint/bone growth, siding with weak pasturns,
loose/flat feet and a multitude of other growth related issues.