I am raising a new Chesapeake female, and she is 9 m0nths old. I can just see her ribs. I run her beside my bike 3-4 times per week for 4-7 miles. There is also swimming for 20-30 minutes during hot weather. I have had many dogs including brittanys, springers, labs etc. I fed Purina or Purina HiPro for most of those years. During cold weather added animal protein and fat. I had healthy dogs doing above. This dog is eating Eukanuba large breed puppy chow, and I believe that her coat, condition, and stamina are extraordinary. It is $40 for 40#. That is expensive compared to Purina, but after spending some time talking with the manufacturer of Iams and Eukanuba I am convinced that it is worth the money. The fish meal is a little hard to get used to the smell, but the Omega 3 fatty acids are worth it. I'll follow with a report as her first season progresses. my two cents worth.