The beef trachea are hollow and come from the windpipe of a bull. The cartilage that lines the outside of the trachea provides the added health benefits of a naturally occurring form of glucosamine and chondroitin. 100% digestible. High in protein, low in fat and filled with natural glucosamine. Beef trachea are slow dried tasty treats your dog will adore. Beef trachea are a delicious and 100% digestible complement to a nutritious diet with no added preservatives.