Some type of gates are necessary to allow passage of the pivot towers without the attention of the operator. Permanent-type fence for irrigated pasture cross fences is more expensive to construct, but may be justified if a strict separation of different groups of cattle is important, such as two different breeding herds or yearling heifers separated from the breeding herd. Construction would normally consist of three or four strands of barbed wire, using a non-electrified gate to allow passage of the towers. Some type of bracing is required at each side of the pivot tower openings to maintain the tightness of the wire. This adds to the cost of this type of construction and is a major deterrent to its use.
Electric fences are much cheaper and easier to build than permanent fences.
Most producers use them for this reason. They have also been shown to be very effective for keeping livestock within the boundaries of the pasture. A more effective electric fence can be made by using two electric wires and double electric gates at the pivot tower openings. Double wire electric fences are normally used when sheep, yearlings or calves are being confined. Single wire electric fence should be one half to two thirds as high as the animal's back.