When it comes to sheep fencing there are various options available.
Electrified high tensile wire and field fence are probably the two most common types of permanent fencing used among sheep producers.
Electra-netting is probably the most common temporary fencing used.
Permanent Sheep Fencing
A five or six strand high tensile electric fence is often the choice of perimeter fencing of large areas for sheep. When using high tensile fence paying attention to the wire spacing is important.
There are a couple different recommendations for wire spacing. The bottom wire is placed at either four or six inches from the ground. After that the next two or three strands are at six inch intervals and then eight and nine inch intervals for the top strands.
Ranchers can electrify as many of the wires as needed. We often leave our bottom wire non-electrified and electrify the remaining four wires (five strand perimeter fence). We do this because of the amount of grass we have that interfers with the bottom charge on the bottom wire.
When the area to be fenced is not as expansive, field fence is very common and often used non-electrified. This type of fence is more difficult to deal with unless you can rent specialized equipment for rolling it out. It does stretch and sag over time or if animals push against it often enough.
Many small scale producers go with the more costly field fence as they are not fencing great distances and can have a secure fence without having any electric fencing to monitor.
Field fence works decently for keeping predators at bay, although the most determined will find a way in, usually by coming underneath it.
Barbed wire only is not recommended material for sheep fencing. The barbs do little to deter the sheep as they can easily avoid the barbs poking them. The real danger to sheep from a barbed wire fence is the wool becoming tangled on the barbs. The sheep will struggle to disentangle itself yet will only further entangle the wool around the barbs and quickly become stuck fast.
Existing barb wire fences have been made useful by placing an offset electric wire or two at the appropriate heights to catch a grazing forehead or sniffing nose.
In areas where the sheep are corralled a wooden slab fence probably works the best. Many cattle corrals can be adjusted to suit sheep. One thing to watch for is the spacing between the slabs. In a high pressure area if sheep think they can get their head through, they'll try.
Temporary Sheep Fencing
Electric netting is the wonder of portable fencing for sheep producers. It does work great as temporary cross fencing. Having some of this on hand is a worthwhile investment. It is easily set up and taken down by one person. Individual roles can be carried under the arm. It can be electrified and it keeps animals in and keeps predators out.
The two downfalls of the electric netting are 1) persistent animals and snoopy lambs can become tangled in it. When we are using it we make a regular habit of checking the fence line. 2) If you have particularly hard or stony ground you will fight trying to push the pole spikes into the ground.
Some producers are making good use of two strand high tensile electric fence as temporary sheep fencing. This has proven successful provided there is enough food on the ground to keep them eating and it allows cattle producers to run sheep without adding to their fence costs.