A Petaluma resident and her star border collie are packing their bags for Germany this week to represent Team USA at the Senior Open Agility World Championship. The Marin Independent Journal reports Annette Thomason, a retired Santa Rosa high school chemistry teacher who now runs the agility program at Marin Humane, will guide her six-and-a-half-year-old dog, Moxxy, through the high-stakes international competition. The fast-paced canine sport r…