If those sows were afraid, they didn't show it. My Dad had a strain of war devil hogs that would charge bulls, and make the bull run.
The bigger danger of the large factory farms is that you are increasing the likelihood of a disease outbreak. To many concentrated in one spot.
He was referring to the industrialized farms where the pigs are kept in a confined space and not allowed to move. They are fed through mechanized means and their waste matter removed on conveyor belts.