I used 50" tall cattle panels when rebuilding a round feeder pen. My problem was a bull kept jumping in, not hogs. I cut a window 4'-6' wide and to a 38" or so height in every other panel around the pen. Works fine and no more bull problems. The key to any feed pen with hogs or cattle is keeping all the corn inside the pen. So if your feeder throws in a 50' circle you need a 55' pen. It has only been up a year now so not sure about fawns but think they will be jumping in when they are 7 months old or older. I have yearling bucks/does in it last year and this year.