American Pit Bull Terrier
This aggressive dog was bred from Bulldogs and Terriers in order to become the perfect fighting dog. The Pit Bull Terrier certainly has no other breed equal to it in this regard. This breed gained attention in the 1980s for its strength and ability to fight for as long as possible. Due to poor training and breeding, Pit Bulls have also been involved in fatal attacks on humans. This aggressive behaviour has caused places like Ontario, Miami-Dade County, Florida, and many other counties, to declare that this breed is illegal to own.
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Japanese Tosa Inu
This is a large to medium sized powerhouse, weighing somewhere around 80-200lbs. It has Japanese and Western ancestry (Mastiff and Bull Terrier) making it the ultimate fighting machine.
This breed has been banned as a pet in Norway, Denmark, Malta and some other countries.
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This is a mix of Mastiff, Bulldog and Bloodhound, which makes it a highly aggressive animal and a dog which should not be kept as a pet under any circumstances. This dog is also known as the Brazilian Mastiff, and was originally bred to hunt boars and jaguars. It is banned in the United Kingdom.
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The Dogo is a mix of Cordoba Fighting Dog, the Great Dane, Dogue de Bordeaux and Irish Wolfhound. It resembles a Pit Bull and is banned in Australia, New Zealand, and many other countries.
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This is certainly the most popular breed in the world, and while this is a beautiful and fantastic animal to keep as a pet, it does have the tendency to become aggressive towards other dogs and strangers if it feels that its owner is under any danger.
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This breed is hard to take seriously owing to its tiny size, but make no mistake; there is a high probability that you will get bitten viciously by this dog than by any other. When a Chihuahua snaps, it becomes extremely aggressive and difficult to manage.
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The Doberman Pinscher
This dog has a reputation for being a great guard dog. They are naturally very protective of their owners and rely on their instincts to gauge when the owner is in danger. They are clever and mostly well-trained, as they do not attack randomly.
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The German Shepherd
The German Shepherd is highly intelligent and aggressive which makes it a perfect guard and police dog. It is also very protective of its owner and gets aggressive when it senses any danger.
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The Jack Russell Terrier
The name says it all, and although this is a small dog and seems far from dangerous, it is a Terrier and will fight back without hesitation. Kids should be kept away from this dog.
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