I jet-ski'ed behind a pomeranian once.
I would guess a horse, just because it's so much bigger. Dogs can run faster, but swimming is another story
I've never heard anyone say they horse paddle when swimming ;-)
horse, the rider would drown the dog.....mmmm
probably a horse because it has more muscles than a dog does and it's legs are longer, giving it the extra pull
A dog but only if it has a small ****.
I would think a dog. Horses are most definitely the strangest looking swimmers.
I'm going to go out on a limb and say a dog.
I'll guess dog.