The fencing that separates my pens is chicken wire and welded wire. Chicken wire will rust out after a few years unless you buy the coated wire. I'm old and it's getting harder as each year goes by. 2 or 3 years ago I knew I had to replace some of the fencing because it was rusting and needed replacing so I put up the welded wire up and some chicken wire because I used 2"x4" welded wire and the males in each pen were fighting through the welded wire so up went the chicken wire. So far it's working well and I'll never have to replace the welded wire as it will outlast me.