Sometimes I think we get too obsessive with their food. I have been pouring over articles and reviews of non-grain foods and raw diets, thinking my very healthy, beautifully coated dogs need to change. Why? Because maybe there is something better? I think maybe I am going overboard. I actually like some formulas of both Canidae and Royal Canin even though they get a bad rap here. I occasionally remind myelf that my 17 1/2 year old dachshund with the shiniest coat around, was fed Alpo and Pedigree for years before I knew about by-products and such. She led such a long, healthy life, I don't think I did her any harm. Still, now that I know, I feel obligated to feed a premium food. Mine don't seem to have a problem with a corn ingredient. The food they are currently on does not have corn but it does not seem to make any difference to the one they previously ate that did contain some corn gluten (same brand -- different diet).
I think if the food is otherwise nutritionally balanced, and your dog is picky, feed what they like. I do avoid by-products now because it sickens me the sort of things allowed by law to be called by-products, especially if it says "meat" by-products.
