I looks like that he sure likes that bone. Better not take that away. You might end up without a hand..
Believe it or not I can, literally, take food right out of his mouth. I found that out when he tried eating a paper napkin along the road when I was walking him, right after we got him. My wife routinely plays with hi by taking his bone and throwing it for him to chase. I do think he knows it's "his" bone and he'll always get it back. That's a big Nylabone and it lasts about a month for him.