Oh what a horrible feeling. I hit a dog once but it was in a subdivision, I wasn't going fast and the dog ran off - I believe he was bruised but I think he was probably okay. A couple of years ago I was driving on a country road when a dog ran out and was hit by a car going fast - the dog was thrown to the side of the road. The car didn't stop. I did, and watched helplessly as the dog died. There weren't any nearby houses so I finally left, there was nothing more I could do. I agree that a dog can run off even from the most careful owners. Leashes break, collars slip, some dogs are diggers and escape artists - they bolt out when you open the front door... My Missie would run off given half a chance and she had no concept of the dangers posed by a car. We always managed to get her back, but I shudder to think of what could have happened...