10. Dalmatian
Dalmatians are very protective dogs and can be aggressive towards humans. They are very active and need lots of exercise. They have very sensitive natures and an excellent memory. This bred is famed for their intelligence, indepedence, and survival instincts.

9. Boxer
Unlike their name suggest, these dogs are not typically aggressive by nature. They are bright, energetic and playful breed. Boxers have been known to be "headstrong", which makes it a bit difficult to train them but with positive reinforcement techniques, Boxers often respond much better.

8. Presa Canario
Originally bred to guard and fight with cattle, an attack by this dog has been described as hopeless for the victim. They are a guardian breed with man-stopping ability, incredible power and a complete lack of fear.

7. Chow Chow
These dogs can be aggressive if poorly bred. The Chow Chow may appear to be independent and aloof for much of the day but needs constant reinforcement.

6. Doberman Pinschers
Dobermans are great guard dogs for their alertness, intelligence and loyalty. They can be agressive dogs when provoked. The typical pet Doberman attacks only if it believes that it, its property, or its family are in danger.

5. Alaskan Malamutes
These dogs are very energetic and active. If they are bored, they can become destructive. That's why this dog needs lots of exercise to be happy.

4. Huskies
Very energetic and intelligent dogs. Not considered a good guard dog because of its personality characteristics and gentle temperament. A 2000 study of dog bites resulting in human fatalities in the U.S. found fifteen such fatalities (6% of the total) were caused by "husky-type" dogs between 1979 and 1997.

3. German Shepherds
These dogs are intelligent and very alert. They are highly used by local authorities such as the police K-9 unit. German shepherds are known to be fearless and confident dogs.

2. Rottweilers
Rottweilers are known to be very aggressive dogs because of their keen territorial instincts. That's why they make great guard dogs.

1. Pit Bulls
A pit bull is a fearless dog that will take on any opponent. They will lock their jaws onto the prey until it's dead. Pit bulls have a reputation of mauling people to death and they are highly sought for dog fighting.