A standard barbed wire fence for livestock usually stands around 50 to 55 inches high is supported by steel posts spaced 15 to 25 feet apart. The number of wire strands you’ll need per length of fence depends on the animal being kept in or out. Sheep, for example, need seven strands, while cattle and horses generally need between 4 and 7.
Aside from its agricultural uses, barbed wire is an excellent security measure. Barbed wire added to the top of an existing fence—often timber of chain link—consists of pole extensions with 3 or 6 strands of wire running between them.