A few years ago in traffic, a dog suddenly appeared in front of me by narrowly dodging the car just ahead of me in the adjacent lane. It was medium sized and might have been an Aussie mix of some kind.
My reflexes didn't even have time to kick in before hitting it going, I'd say between 25 and 30 mph. I was riding an old 750 Kawasaki 2-stroke, and pretty much just knocked the dog partially out of the way before bouncing over at least part of it. Actually, it happened so fast that I was never sure exactly what happened, but I managed to keep the bike upright (barely). I don't know what happened to the dog, but it was gone when I turned around and went back.