In recent years there has been a considerable increase in the housing of sheep in the United Kingdom. This has taken place primarily pre-lambing and to a lesser extent for the finishing of lambs.
Drinan and Ferguson (1981) found significantly faster growth rates and heavier carcass weights from lambs shorn 10-12 weeks prior to slaughter. Younis et al. (1977) and Salmon and Owen (1981) found increases in voluntary feed intakes and improved rates of liveweight gain in shorn as compared to unshorn lambs. Food conversion ratios have been found to improve in some trials but not others.
The effects of shearing store lambs that were being finished indoors was investigated using 24 April born Suffolk X Mule lambs housed in individual pens from the 17 October 1985. Lambs were randomly assigned to one of three treatments. Group A and B were shorn at housing; Group C was left fully fleeced. Five weeks after the start of the trial Group B was shorn for a second time. The lambs were fed ad-libitum on a silage-based complete ration containing 6.1 MJ NE/kg. of Dry Matter.