When my wife was a child her dog kept her from walking on a Coral Snake.
We grew up with an female Irish Setter and she followed us kids everywhere. One morning in the middle of summer us and some of the neighborhood kids were playing basketball and she was standing guard in the road near a ditch line a little ways from the driveway where we were playing, marching back and forth.
The ball went in that direction during the game and she leapt into the ditch before any of us got there and came out with a three and a half foot Copperhead. She grabbed it right behind the neck and killed it deader than Julius Caesar. One of the neighborhood parents heard us talking about it and came out and made sure it was dead and disposed of it and checked the ditch line just to make sure. Sandy was a good protective girl!