One of my riding partners hit a dog as she was going about 25mph down a hill. The dog was okay, but she was NOT (torn rotator cuff, lots of scrapes and cuts, etc.). We jotted down the address where the dog resided and called the sheriff and animal control. Owners have to take responsibilities for their pets. Now, whenever I encounter dog not on a leash or within a fence, I slow down and prepare to dismount. You just never know.