fencing - Chicken wire or wood plank horse paddock?

We are in the process of acquiring 3 alpacas. We have almost finished the barn so they have a home and a safe place to sleep. The people who owned our place bred horses so we will be housing them in the horse paddock which has a 3 beam typical paddock. Is this enough to keep them in? We thought of covering it with chicken wire to keep them safe from predators during the day, although they will be in the barn at night. I'm also looking at 4" by 4" fencing to see if that would work. ( looking at difficulty in putting it up and also cost)
I have googled and searched here but I don't see a clear answer.
Chicken wire ok to keep them in and predators out?