Pit bulls are one of the most dangerous dog breeds based on fatal attacks, along with German shepherds and rottweilers. However, these breeds are not necessarily responsible for the most bites overall.
An investigation in Colorado found that labradors were responsible for the majority of dog bites in the state. These bites were serious enough to seek medical attention but were non-fatal and tended to be on the hands or other extremities. Small breeds are also common biters, with Lhasa apsos and shih tzus being noted aggressors. However, their bites are typically less severe due to the dogs' small size.
Larger breeds are noted as being more dangerous due to their jaw strength. Some breeds are noted for having more aggressive tendencies, such as chow chows and presa canarios. Presa canarios in particular have been implicated in several serious attacks despite the relative rarity of the breed. Doberman pinschers, malamutes, huskies, Saint Bernards and great Danes have also been involved in fatal attacks.
According to the American Veterinary Medical Association, any dog can be dangerous in the right circumstances. The association considers breed to be a poor predictor of dog-bite risk, citing factors like socialization and training as more relevant factors. They also note that most statistics may not be accurate because they rely on the victim's or investigating law enforcement officer's identification of the breed, which is not always correct.