I am just about finished with the first bag of food that Choppers breeder reccommended. He seems to be doing pretty good on it,but I am looking at my options. They refered to this as a maintinance food. It is Bites and Bones from Tractor Supply. I see a lot of folks here using feed with a 2 number designation in the name. Can you all bring me up to speed with these? I don't have a problem using Bites and Bones,as long as I'm not missing out on a better food for an active dog. Thanks all,Rockdog.