The Australian Cattle Dog goes by many names — Blue Heeler, Red Heeler, ACD, Hall's Heeler — but its owners have a universal name for it: everything. The most athletically gifted dog they've ever met. The most infuriatingly clever animal they've ever owned. The most devoted, loyal, and relentlessly energetic companion they could have possibly chosen. Developed in 19th-century Australia to herd cattle across vast, unforgiving terrain, the Australian Cattle...