Crutching

Crutching refers to the removal of wool from around the tail and between the rear legs of a sheep. It can also refer to removing wool from the heads of sheep (wigging) or from the bellies of male sheep (singing)

After centuries of artificial selection, domestic sheep have denser and longer wool than their wild forebears, which may require human intervention to maintain. Sheep with heavy fleeces of wool often develop stains or on their rear ends from faeces. In ewes, urine can also stain the wool. To avoid discomfort to the sheep and damage to the fleece, graziers remove the wool (and any dags) from the sheep.

Urine and watery faeces from eating spring grass can also lead to myiasis (fly-strike), which occurs when flies lay eggs in warm, damp wool and the fly larvae grow and eat into the sheep. Crutching is an effective way to help prevent this; in some areas, crutching is carried out at the start of the fly season (which depends on local climatic conditions) and may be needed at intervals of 6–8 weeks in high fly risk conditions.

Rams and wethers may also be rung (crutched) on the belly around the pizzle (penis) to prevent fly-strike there.

Wigging (removal of wool from the head of sheep) is carried out to prevent the sheep from becoming "wool blind", in which the wool covers the sheep's eyes. It also prevents accumulation of grass seeds and burrs in wool around the head as a sheep grazes. Both these problems are more severe in breeds with heavy wool growth such as Merinos.

In addition, ewes are generally crutched prior to lambing if they are not "offshears" (recently shorn), in order to provide the newborn lamb with a cleaner suckling area.

Crutching is generally carried out in shearing sheds, using shearers and the same tools as for shearing the entire fleece, as crutching is simply shearing only a portion of the animal. Blade shears may be used, especially where an individual sheep is particularly dirty, or flystruck. Generally, whole flocks are treated together. A mechanical shearing handpiece is used, and the crutchers sit the sheep between their legs and shear the required portion of the sheep, leaving the main fleece to continue growing. There are also many varieties of crutching cradles which allow the sheep to be crutched with less physical strain to the operator.

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Wikipedia