@hannah102 I don't know that I would... unless they're specialized for dogs. And I think dogs produce their own Vitamin C but don't quote me on that IANAV.
@hannah102 I do. Since I make my own food, I did check with my vet to see that the vitamins recommended in the recipe were safe. I wanted to make sure it was complete and balanced.
@hannah102 Considering most dog food is complete, there should be generally no need. Maybe go ask over at /r/AskVet for their ideas or the area? 