yes and no true you can make any dog mean but some do have genetic issues that make them more likely to try some thing. I groomed for 5 years cocker spaniels are way up there as the worst. 1 they don't give warning when they will try to bite and 2 they always go for the face if they can get a shot at it. its funny pit bulls rottweilers and other scary dogs are just big and happy never a problem. chiwawa just sit and shake scared of there own shadow and poodles know the routine so well they practical trim them selves very few have problems. but cockers are the worst. dalmatians can be a problem you either can or can't work with them but they will let you know very clearly to back off. and chows you got to be careful with its not that there exceptional nasty is just a breed that's a 1 man dog.
It's more about which one are more dangerous overall than aggression specifically.
That said, bull-baiters were originally bred to be aggressive for their task, so there's that.
Cocker Spaniels are shifty. So are Shiba Inus, German Shepherds and Corgis. I’m a vet tech and if we see any of those breeds come in we immediately get a muzzle and 9.9/10 times they need it (Especially the Shibas, Shepherds and Cockers). Surprisingly, very few Chihuahuas ever give us issues. The most they do is wiggle and worm around. Same for Pits and Rotties. They never stay still but they hardly ever show us any aggression or try to bite.
its breed specific when they've been bred specifically for aggression, such as with pitbulls, who, despite being just as nice as other dogs, absolutely will snap and attack even if they've been raised "correctly" in loving homes
Pitbulls are HISTORICALLY one of the most wonderful dogs. They used to be known as "nanny dogs" because of how good they were with children.
Dogs in general dont bite at someone for no reason. Sometimes dogs can be aggressive due to trauma or mental illness.
If your friends have pitbulls and they claim their dogs are vicious then your friends either trained them to be aggressive, they arent as good dog owners as they claim to be or the dogs could be sick or have come from a previous abusive family
That said, bull-baiters were originally bred to be aggressive for their task, so there's that.
and all the other dog owners I know are good owners except when they own pitbulls
Dogs in general dont bite at someone for no reason. Sometimes dogs can be aggressive due to trauma or mental illness.
If your friends have pitbulls and they claim their dogs are vicious then your friends either trained them to be aggressive, they arent as good dog owners as they claim to be or the dogs could be sick or have come from a previous abusive family