Well, I have a query regarding the entire Eagle, holistic, organic, raw dog food supporter here. I have two dogs of large breed. Iâm feeding them Purina pro plan till today. They are now 14 years of age and have never suffered from any diet related problems such as skin, allergy, GI, coat etc. Why do people suggest not giving Purina pro to their dogs? How do you compare dog foods? Please give me the reasons and also list few best foods for dogs?