I worry about four-legged dogs too! That is a really weird story, and I never thought of that happening. OMG SF is going to go after you mercilessly when he reads this.
When doesn't he?
I found out the best way to deal with a dog chasing you when you're riding is to slow down (so they don't knock you down at speed....road rash is probably worse then a dog bite). Then pull out your water bottle and spray the dog. That usually does the trick. Also, it's pretty hard for a dog to bite you when he's running....they're to busy trying to breath. Your biggest danger is getting knocked down.
The scary thing is that's not even the weirdest dog story I have. I had a far stranger one. I call this one "Doggone Steering Problem".
It started one day when I was training for a duathlon. I was in time trial mode and I was approaching a t-intersection where a guy in a red pick up truck was sitting. Now I have a safety habit that I've used over the years that when I approach a intersection or cross road with someone siting at it, I wave to them. If they wave back, I know they've seen me and won't pull out in front of me. So I waved at this guy and he flipped me the bird and pulled out in front of me. I had to go into the ditch to avoid getting fan over and ended up doing an endo over the handlebars and got a bad case of road rash.
A few days later, after I had recovered from the fall I went out riding again. I went out riding on some back country roads. You know the kind with the chip and seal pavement? Well the road I was one had a fresh coat of tar and was jet black. Which could explain why I didn't see that pot hole. I learned another hard lesson. If you ever wipe out on your bike, before you ride it again give it a good inspection to make sure everying it still tightened down. Well when I hit the pot hole the aerobars I was resting on came lose. I came within a hair of doing another endo. I somehow managed not to fall. Stopped, fixed the bars and kept on riding. Soon I entered the small town of Commercial Point (Home town of Sarah Fisher the race care driver). As I was passing a soft serve ice cream stand I heard this guy shout. "Dont run into any pick up trucks!" Damned if it wasn't the guy who ran me off the road a few days before. So I got off the bike and went over and started giving the guy a piece of my mind. He in turn took a swing at me. I duked the punch and triped him up and then stomped on his chest when he fell down. That took the wind out of him and I finished giving him a piece of my mind. I then got on my bike and got the hell out of town before he could get back in his truck and run me over.
So off I go out of town and I turn off on another back road to lose and pursuit. Well a few miles down the road I see this petite lady walking 3 Aerdailes by the side of the road. I slowed down and as I got near I noticed that the dogs were pulling at their leashes to go after me. So I asked her "Do you have a hold of them?" She said "Yes" and no sooner said that and the dogs broke lose from her. Needless to say I started sprinting for my life with these three dogs hot on my wheel.
Soon I hit this steep hill and I started stomping up it. Now in cycling when you stomp up a big hill you tend to hold on to your handle bars tight and look down at your wheel, occasionally looking up the road. Well I stomp a way up the hill and look behind me and the dogs are still there. I stompe a little further up the hill and look back and I'm starting to drop the dogs...I stomp some more and look back and the dogs are gone....I then look up the road and about 10 yards in front of me is a full grown steer out in the middle of the road!
Screeeeeech! I come to a quick stop. I get off the bike, chase the steer back into his pasture. I propped up the fence he had knocked down and then went to the farm house and told the farmer that his steer had gotten lose. I helped the farmer fix the fence and then asked him if he could give me a ride home.....I didn't feel like riding any more that day.....I figured God was trying to tell me something.