I would also like to point out that should you and your Veterinarian decide to add fresh whole plant-based foods to your dog's diet, that you do so very gradually and start out in very small amounts so that their little systems adjust to the changes without discomfort (for them or you).
Here is a list of plant-based foods that you should NEVER FEED TO YOUR DOG:
Grapes, rasins, & currants
Pits from peaches and plums
For a complete list of ALL things you should NEVER FEED YOUR DOG and why, go to: http://www.peteducation.com/article.cfm?c=2+1659&aid=1030