Most people don't realize it, but those silly little wiener dogs can be pretty fierce themselves. Dachshunds were bred to hunt badgers (long and low to be able to get into the dens) and badgers are no push-overs.
I actually used to own a little red Dashshund and he picked fights with bulldogs and German Shepards around these parts. Actually, a German Shepard almost killed him one day and our little 11 pound Mountain Feist saved him by tearing the Shepard's throat out.
Sad part is, that kinda stuff is more rampant around here than other animal attacks. Like the Shepard above was a wild dog, a dog that had been thrown out and forgotten. We get those all the time. It's truly disheartening, really.