My in-laws have electrified barbed wire and electrified wire fencing to keep the cows in. Freyja discovered it when she was about 4 months old. After the initial screeching panic, she calmed down and to this day respects the fencing. I've been shocked by the fence and can testify that it has a powerful zap (enough to keep the steers in). Freyja was fine other than her initial reaction.
Freyja GSD- 6/21/10
Bevin (princess kitty) 08/27/07
Porsche: kitty 7/2012
Teddy (collie)- 1990-09/13/2006
Franklin (collie) 1996-06/26/2006