EDITED to add more.
I'm sorry, I don't think I was clear about the vitamins in Dr. Harvey's.
This is just my opinion. Everyone has to make their own choices. When you use Dr. Harvey's you are using a whole food supplement, not a vitamin mix.
Most nutritionists haven't actually tested Dr. Harvey's food to register the vitamin/mineral content/ nutritional data. Because the vitamins/minerals contained in the food are from herbs/veggies, rather than a synthetic vitamin mix, nutritionists just don't trust that it is nutritionally balanced. I can understand where they are coming from. However, anecdotal evidence from pet owners suggests that it is. It's up to the individual pet owners to decide.
Dr Harvey claims that the pre-mix products make up a complete whole food nutritional supplement. I spoke with him last year, and he told me that most people do not add additional vitamin/mineral supplements to his pre-mixes, (if their dogs are healthy to begin with.) He said that their dogs do just fine. Some add probiotics/enzymes.
It's really a matter of personal choice whether to add an additional vitamin supplement or not. I think a lot of animal/human nutritionists are concerned about having a balanced vitamin mix added to food, when in most cases just eating the right mix of food itself is fine. It is the quality of the PROTEIN is what matters the most. Buy the best-quality meats/fish/chicken that you possibly can afford. Organ meats, which most people shy away from, are extremely nutritious. And they are less expensive than lean cuts of meat.
I use
Animal Essentials Herbal Vitamins and
Animal Essentials Calcium (which are whole food supplements,) when I home cook from scratch. I've been using it for almost 2 years, and Nikki's doing fine. I probably don't need to use the herbal vitamins, but I do it because I can't always afford the best food. Calcium is a necessity, though, and I personally like using Omega 3 oils.
(After years of using multi vitamins and herbal supplements myself, I have backed off most of them, and instead, started eating properly. The doctor said that the only thing I was low on was Vitamin D, and that is mostly because I don't go out in the sun enough.)
IMO, if we are generally healthy, there are enough vitamins and minerals in good quality meats/poultry/eggs/fish, veggies and fruits, to sustain our health, and our dog's health without overdoing supplements. But, you have to seek out and eat good quality food.
The reason why commercial dog foods have a vitamin/mineral mix added to their food is that the quality of the proteins are very poor, and their high-heat food processing methods remove vitamins/minerals, so a supplement must be added back in to make the food nutritionally complete.
Remember, this is just my own personal opinion, and everyone has to make their own decisions.