Shearing — the annual removal of the fleece — is a necessary welfare procedure for domesticated sheep whose wool would grow continuously without the seasonal shedding of their wild ancestors. While shearing is welfare-necessary (heavy unshorn fleeces cause hyperthermia, mobility problems, and blowfly strike risk), the shearing process itself causes acute stress that can be mitigated through good practice.
Most domesticated sheep breeds have been selected for continuous wool growth and lack the seasonal moulting of their wild ancestors. Unshorn sheep experience: hyperthermia risk in warm weather (the dense fleece acts as insulation), reduced mobility from fleece weight, increased blowfly strike risk (wet, soiled fleece provides ideal conditions for fly egg-laying), eye conditions from wool covering the face, and progressive welfare decline. Regular shearing is therefore a welfare necessity, not merely an economic activity.
Research using cortisol measurement, heart rate monitoring, and behavioural indicators consistently shows that shearing causes acute stress in sheep. Stressors include: physical restraint in an unfamiliar position, noise from shearing equipment, contact with a novel person, separation from flock-mates, and the sensory experience of fleece removal. The duration of acute stress is relatively short (the shearing procedure itself) but significant. Cortisol returns to baseline within hours in most animals.
Shearing welfare can be improved through: minimal pre-shearing fasting (sheep should not be withheld from food and water for extended periods before shearing — 12 hours maximum in warm weather), handling sheep calmly to the shearing area (reducing pre-shearing stress), using well-maintained equipment (dull blades cause cuts and require more passes — increasing duration and trauma), skilled operators who complete shearing efficiently and without unnecessary cuts, treating cuts promptly, and returning sheep to water and feed immediately after shearing.
Shearing timing affects welfare: early spring shearing (before lambing) increases hypothermia risk if cold weather follows — appropriate shelter provision is essential. Shearing lambs at foot with their mothers requires additional care to maintain ewe-lamb bonding. Shearing lactating ewes causes stress that temporarily reduces milk let-down — adequate housing and nutrition support recovery. In cool climates, appropriate shelter for newly shorn sheep, particularly in overnight temperatures below 10°C, is a welfare requirement.
Shearing cuts are common — skilled shearers minimise them but cannot eliminate them entirely. All cuts should be treated promptly with antiseptic to prevent infection and blowfly attraction. Significant cuts (particularly to the udder, perineum, or deeper tissues) require veterinary attention. Operator training, regular blade changes, and appropriate restraint reduce cut rates. Farm assurance schemes may require recording of shearing cuts as a welfare indicator.
Research into alternatives to traditional blade shearing includes: biological shearing (Bioclip — treating with epidermal growth factor to cause natural fleece break, enabling fleece removal without handling — limited commercialisation), selective breeding for natural shedding breeds (Soay, Wiltshire Horn, Easy Care — eliminating shearing requirement but sacrificing wool production), and robotic shearing (under development — potentially enabling shearing without human-animal interaction stress).