pit bulls (american pitbull terrier) - breed origin: USA. breed group: terrier. weight: 30-60 lbs. life span: 12-15 years. the dog was bred first to bait bulls and bears. when baiting bulls was deemed inhumane, ratting (a sport where a number of rats were placed in a pit for a specified time with the dog) and dog fighting became more popular. The APBTs was used in both sports, and its prevalence in being put in pits with rats, or other dogs led to "pit" being added to its name.