How many times have you heard a basset hound, Beagle, Collie having attacked people or other dogs and how many times a pit, or Rottweiler? Nough said!
The reason for that is that those other breeds don't make headlines when they attack someone. It's typically a bite and a release. Pitbulls are bred (like Boxers), however, to latch on and not let go, resulting in greater harm, which results in an increased likelihood of making the news.
