Elecified net fencing is sometimes necessary to stop stubborn predators or to keep chicken inside when they must be fenced tightly. It's more expensive than individual, and if left in the same place for too long, grass will grow through the bottom wires, making it almost impossible to remove. Still, it has its uses. We use it to surround our broiler areas, while we use one- and two-wire fences for our hens. This works well because broilers won't use a lot of space anyway, so you might as well yard them tightly. Hens like elbow room.
The type sold as electric garden fencing is the best. This comes in rolls about sixteen inches high, and can easily be stepped over. The usual electronetting, designed to keep sheep in, is about four feet high and is a real nuisance.
The best electric fencing comes from Premier (whose Web presence is unfortunately not all it should be).