Special Features:  - All natural, FDA approved knuckle bones that're sourced from grass-fed, free-range, Brazilian cattle - High in calcium, iron and zinc which helps your dog's body fight off infection, maintain a healthy immune system, and provide energy to help support brain functions - Barkworthies are preservative-free, hormone-free, and antibiotic-free. Contains no grains or gluten - Long lasting for medium to large breeds and provides a durable chew for aggressive chewers. - Chewing also supports dental health by cleaning teeth of plaque and tartar Country of Origin: Brazil, Colombia Ingredients: Beef Knuckle Bone Guaranteed Analysis: Crude Protein (Min.)28.0% Crude Fat (Min.)15.0% Crude Fiber (Max.)0.4% Moisture (Max.)6.0% Serving Size1 oz. Caloric Content: 3,502 kcal/kg, 2,919 kcal/serving Made in the USA / USA Made