The Mastino Napoletano, or Neapolitan Mastiff, is huge and robust. That doesn't imply they're hostile, but they can kill if untrained.
Breed to herd animals, Perro de Presa Canarios. Their name means "Canarian catch dog," since they capture and help sheep go home.
They're popular in their country for livestock guarding. If trained to guard their area and owners on a ranch, they're terrific.
Rottweilers are calm and protective with those they trust. Early socializing prevents kids from mistaking a postal carrier for a safety danger in a hurry.
The Italian mastiff Cane Corso protects, guards, and tracks. Mastiffs are among the most prohibited breeds, but not because they're less predictable or violent.
Despite their menacing look, Doberman pinschers are devoted, caring pets. Though smaller than mastiff breeds, they can still do considerable injury if they bite.
The pure-white Dogo Argentino was developed to hunt big game in Argentina. Bright, bold, and athletic, their tough, persistent character demands strong guidance from the start.
Brazilian mastiffs, or fila Brasileiros, are great trackers. As hunting and security dogs, they're one of the few breeds strong and aggressive enough to handle huge game animals.
It's illegal in other countries, but Japan allows it, and the breed's ancestry makes it more prone to attack other dogs, even if reared gently in a loving setting.
Pit bull bites are dangerous, hence many nations use the "better safe than sorry" approach and ban or limit ownership.