Mine let a chicken out of the cage and was unattended with it and no harm done. Its all in the owner's training. ANY dog can be made mean and when it is a powerful dog then that is when bad things happen. They can also be the sweetest thing in the world like yours.
Maybe someday people will realize that pitbulls are good dogs to! I always hear that back in the day they were the "nanny dogs" because they we so affectionate with kids. Mine loves my girls and will let them do anything and likes all the animals too. She does chase the horses and goats if she thinks they are getting out of line though. Here's a pic of my killer.