I used to be a delivery guy for FedEx and have had some weird things happen to me while making some deliveries. Nothing quite like this though. Poor guy got chased around by a dog who was probably just being playful/protective. I could be very wrong about assuming that.
It's always interesting to see how all sorts of animals interact with one another and sometimes it's not always a positive encounter. In Wyoming, we get to see a variety of different animal interactions.