The importance of the radical mules operation and tail length for the control of breech strike in scouring Merino sheep.

While the radical Mules operation reduced the incidence of breech strike from 59% to 13% in scouring sheep, the problem was further alleviated by docking lambs' tails at the correct (medium) length. Docking lambs' tails very short strongly predisposed radically mulesed ewes and wethers to faecal soiling and breech strike (20% struck). Radically mulesed sheep with tails docked midway down the vulval orifice in ewes, and the corresponding length in wethers, were rarely struck (3%) and did not appear to require crutching to prevent breech strike associated with scouring or urine staining.