Sheep farmers in Australia follow a controversial practice called mulesing. Mulesing is the removal of strips of wool-bearing skin from around the buttocks of a sheep to prevent flystrike. The wool around the buttocks can retain feces and urine, which attracts flies. Mulesing involves cutting off the skin around the buttocks of merino lambs, often without anaesthetic.

Around three-quarters of merino lambs – prized for their soft fleece – are mulesed when a few weeks old, about 20 million animals. Traditionally, this is conducted without pain relief, though the industry is now introducing local anaesthesia amid fears of a worldwide movement against it.

Major retail chains have over the years condemned the practice as unacceptable and have pledged to seek wool from non-mulesed Australian sheep or from other countries. The Australian wool industry says alternatives to mulesing are not yet viable or are not cost-effective. There are some proposals like skintraction, liquid nitrogen applications and clips but these are yet to win acceptance.

Mulesing was developed in 1927 and since then it has been a routine surgical husbandry procedure for the majority of sheep in Australia. The pain of mulesing is similar to that of castration but it lasts longer, for up to 48 hours.