It started with the question: how do we make use of every part of the chicken? When we "part" a chicken into the various cuts (breast, thigh...etc.) we are left with what we call the chicken frame which still has a decent amount of meat on it. We love making our chicken bone broth, but there are still hundreds of lbs of leftover chicken frames, kidneys and extra trim. So we grind it up to feed to our pup.