Dogs have a prey drive. It happens with Huskies, German Shepherds, Dobermans, Rottweilers, and Chihuahuas. Most of that is nature - Our American Eskimo Dog, which is a type of Spitz, went after small stuff like baby bunnies constantly. My mother-in law’s Doberman goes after adult rabbits and squirrels.
Unfortunately, this type of thing happens. I wouldn’t wish losing a pet this way on anyone, but the unfortunate truth is that this is way more common than you think, and it is not breed-specific. You just hear about Pits because people have a general fear of them, as it was with German Shepherds during the second world war (true, according to someone on my dialysis shift) and Rottweilers and Dobermans in the ‘90’s.
Yesterday my dog killed a cat that came into our yard. The neighbors feed the things and they are running around like rats in the street. These are the same people feeding the wildlife and turning our parks into goose crp filled no-go zones.
If you have a pet don’t let it roam into other peoples spaces. Dog or cat.
If it was my cat, and I was armed, I would’ve shot the dog and not hesitated.
I carry a folding knife all the time, and I would not have hesitated in attacking the dog with it.