Heartland Select Grain Free features the NutriSource exclusive “Good 4 Life” system and is made with the finest quality ingredients available.? NutriSource Heartland Select Grain Fee combines Bison & Chicken and carefully selected ingredients in the precise blend to balance all essential nutrients necessary for optimum health, well being and long life. Readily available nutrients in Bison & Chicken go to work on the inside, resulting in less waste.