holy crap your dog looks a lot like my dog xochitl:

she's an amazing trail dog. i didn't have to train xochitl at all. she just followed me instantly. herding dogs own. one trick my friend used to get his dog aclimated to riding with him was to first just take his dog running. once he was confident his dog would stay with him, he took him biking. often too i think the just the high paced activity keeps them from getting distracted. it can be tough on their paws at first, so just taking them running first can help their paws toughen up at a more gradual pace. sometimes too you have to buzz their arse with your front wheel to remind them where you are and to stay out of the way.