Did you know that the breeds that are more likely to bite are the ones people rarely think about. Here's some examples of breeds that can have a "bad attitude": Chow Chows, Dalmatians, Papillons, Old English Sheepdogs, Beagles, Lhasa Apsos, Toy Poodles, Chihuahuas, Golden Retrievers, Labrador Retrievers, Dachshunds, Jack Russell Terriers, Cocker Spaniels, Pekingese, Miniature Pinschers and Yorkshire Terriers.
Now, here are some gentle breeds that can't seem to shake their "bad dog" images: Boxers, Bulldogs, Great Danes, Mastiffs, Bullmastiffs, German Shepherd Dogs, Rottweilers, Giant Schnauzers, American Pit Bull Terriers, and Doberman Pinschers.
It's the individual dog that matters, not just it's breed.
Please remember, no dog is born a killer, humans are almost always the reason behind any dog-related case. Whether the dog was abused, trained to attack/fight, irresponsibly trained or handled, poor socialization, teased, threatened, cornered, or injured, a human was very likely the cause of the bite.
Rottweilers, German Shepherd Dogs, and American Pit Bull Terriers have the strongest bite forces recorded (in order).
But, Dachshunds, Chihuahuas, and Jack Russell Terriers have been recorded as "the most likely to be aggressive". Sure these breeds don't do a lot of damage if a bite occurs, but these breeds have a higher tendency to be aggressive than many large breeds. This is mostly due to poor socialization, little training and little or no discipline from the human. Also, because of their size, when a bite occurs, many people choose not to report it.
Other notable breeds, in order, include: American Pit Bull Terriers, Rottweilers, German Shepherd Dogs, Siberian Huskies, Alaskan Malamutes, Doberman Pinschers, Chow Chows, Presa Canarios, Boxers, and Dalmatians.
Now, the majority of these breeds are happy, calm dogs that enjoy their life spent as family companions. These are breeds that can be territorial and protective of their home and people, one must respect this to prevent any accidents. Typcially it's the biters that appear on the news, but those few dogs are a minority when compared to the dog population. The many friendly and obedient dogs in the world don't get anough awareness, and that's just not fair.
Pitbulls, Rottweilers and Dobermans.
I heard that the most passive ones are German Shepherds.
Perhaps this information might be useful for you: 
However, in this page it says German Shepherds are aggressive but Labrador Retrievers are more passive. 
It seems that the choices over which dogs are safe to keep around children is inconclusive and questionable.
I myself would not have a dog in a household with children under 10 years old at all. Unless the dog is trained in obedience school.
In a household, having both children and dogs is a double edge knife, sometimes its the dog, sometimes its the kid, but the truth of the matter is that you can't be there all the time to insure both will be safe at all times. Bites occur much too common and dog bites injuries are a major concern in the nation's emergency rooms.   This one in particular one of those "unprovoked" of a dog who ate a newborn baby!  Another with general info about Kid dog bites 
Dog attacks are attacks on humans by feral or domestic dogs. Dog attacks often occur because of the close proximity of dogs to people, and such attacks have become the focus of increasing media and public attention in the late 20th and early 21st centuries. It is estimated that two percent of the US population, 4.7 million people, are bitten each year. In the 1980s and 1990s the US averaged 17 fatalities per year, while in the 2000s this has increased to 26. 77% of dog bites are from the pet of family or friends, and 50% of attacks occur on the dog owner's property.
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