When I was a lad of about 10 years old, I had a paper route, on which neighbourhood dogs harassed me. An older chap, a German machine-shop owner, had his wife patch me up one day, cleaning then bandaging my dog-bit leg.
After this he took me out to his shop and gave me a WW1 Bayonet similar to that one, but with a serrated back.
I carried that knife (belt scabbard for it) with me every day from then on and only had to poke a couple dogs to stop that problem.