After seeing another dog die from a pit bull attack, I feel compelled to write. The opinion that pit bulls are "mean because of the way they are raised" is often not the case.
Both of the dogs I took care of that died were attacked unprovoked by pit bulls that were in families that raised them responsibly.
Just as a retriever is bred to hunt birds -- an instinct you can't stop -- many pit bulls have a genetic tendency to attack other animals. When they do, they are extremely powerful and don't quit.
I have never been bitten or growled at by a pit bull -- they are very friendly. But when the instinct to attack another animal occurs, they cause serious damage, or death. They don't bite people any more often than other breeds but when they do, it's bad.
The aggressiveness toward other animals and damage they do is not because of "the way they are raised" -- it is usually due to a genetic instinct not in the control of the owner.
-- Kathryn Hawkins, DVM