I breed and show poultry. The stuff you see is straw. Since I am on heavy clay soil it gets very wet in rainy weather so I spread lots of straw in the dog yard to keep them dry and clean. The bone is a large beef bone. I get a sack full of bones once a week free from the abbatoir in the next village. I give them whole, then after several days chewing all the meat off, I saw it in half so they can get the marrow out.