American Bulldog
American bulldog are primarily used to guard farms and catch large animals during hunts. These doggies are very strong and energetic.
Neapolitan Mastiff
A lot of law enforcement agencies all over the globe use these dogs for protection. It is due to the fact that they immense courage. This breed was near extinction after World War 2, but Premier Piero Scanziani set up a breeding kennel to guarantee its survival.