Yellow Lab, started her on Chicken Soup from my research on dog food. The dog forums would make you think you were an animal abuser if you fed a dog any less. Chicken Soup was the cheapest of the good stuff.
The results were, constant diarrhea, itchy skin, and poor coat. We tried some other expensive "good" food, same thing. We switched to Iams, which is highly recommended against on the dog forums, and she did fantastic. Been feeding her Iams for 2 years.
Mother-in-law had the same experience with her 2 Golden Retrievers.