Open Range Collagen Bully Sticks are single-source protein treats that provide essential nutrients. vitamins. minerals. and they are very high in chondroitin and glucosamine. Collagen is found below the top layer of skin (two layers below the tough outer layer that is used for leather and upholstery and notably rawhide) and is one of the key elements in connective tissue. Collagen is like a glue that helps to hold things together.Excellent source of chondroitin and glucosamine. which help to reduce inflammation in the joints and support healthy skin and a beautiful coat. A fantastic chew treat that helps to reduce plaque and tartar. contributing to healthy teeth and gums. As with all chews, Collagen sticks help to reduce boredom. and release endorphins while your dog chews, keeping your dog mentally stimulated and happier!