Methods for preparing dog food compositions formulated for small dogs with certain body conformation types comprise categorizing a small dog for which the food composition is intended. Preferably the small dog is categorized as a robust or athletic body conformation type. The methods further comprise formulating a dog food composition to contain feed ingredients and amounts thereof based on the categorizing of the small dog. The protein and fat content of the food composition can be adjusted based upon the robust or athletic category for a particular dog or dog type. The categorizing uses a modified body mass index, namely body weight/[(height−height of the sternum to the floor)×body length]. In some embodiments, the categorizing can use skin fold measurements.