26. Fila Brasileiro

This incredibly large dog, which originated from Brazil, has the ability to weigh up to 100 pounds. And due to it’s size, it is not suggested that inexperienced dog owners get one for their home, especially if they have young children. Due to its strength, intelligence, and massive body size, this dog requires someone that can handle its exuberance for outdoor activity. It is also said that if the Fila is left alone or is not given enough attention, this dog will go into destructive and aggressive behavior. Plus the fact that it doesn’t get along with other dogs is another concerning characteristic.

27. Chow Chow

Despite their unbelievably adorable and cuddly appearance, Chow Chows are actually known to be quite aggressive in behavior. This large canine can approximately reach up to 70 pounds in weight. Even though they are immensely loyal to their owners, they have been known to turn on them in particular situations. The Chow Chow, which was originally from China, was bred for use in hunting and guarding its master in its early years of existence. It is also well known to be very wary of strangers.