So what your saying is that you fight dogs?
seriously, 50?
I do agree with what is being said though. For the most part, it is upbringing. Now some things just can't be taken out of a dog. I have Akita's and we brought them up really gentle, really nice dogs.
But last weekend we went to the dog park (been there at least 2 dozen times) and the male and the female took off after a dog after being there literally 1 minute, my female pig rolled the dog, and then my male grabbed it by the leg and started to body slam it over and over and over. This is exactly what they used to do in Japan (the female lured bears and the males attacked for hunting)
I gave the lady my vets name and number and stopped at the vet and told them I would cover all charges. 260 dollars because it had 8 punctures, had to be sedated, stiches, some sort of tube in its leg, pain meds, anti-inflamatory, anti-biotic.
My point to this story is that even though my dogs are totally calm, were raised to be very gentle, something turned on in them and they still attacked. Same thing with Pit's. I think a pit may be the one of the more loyal breeds (hell I read an article about a pit jumping through a window and dragging its owner to a door when a fire broke out) but it does not mean that they can be treated like any normal breed. They are aggresive.