This is a subject very close to my heart.
Started Puggles out on Eukanuba. As I learned more about it, I didn't like the preservatives in it, so I switched to Flint River Ranch. I was very happy with it, until we found out all of the allergies that Prancer has. She couldn't tolerate many of the ingredients. Also, in time, Puggles developed a wheat allergy, so that was out for her, too.
Prancer's allergies are so extensive that I read about 6 dog nutrition books and developed my own dog food. I'd bake it about once a month for her. She'd get 1/2 c. in the morning and 1/2 c. of raw meat at night, so I called this a modified BARF diet. BARF means bones and raw food. I shared my recipe with my vet and he agreed that it was nutritionally balanced for her. He even gave the recipe to some other patients who couldn't find a commercially available food because of allergies. During this time, Puggles ate Nutro Lamb and Rice.
Then, one day as I was surfing to find something that would agree with her, I found Azmira Dog Food. They make an organic food that has none of the allergens that have plagued Prancer in the past. So, we've been using that for about 3-4 years now with much success. I get it online at
www.petfooddirect.com. Both of my pugs eat that now.