Breeding and Genetics of Sheep SELECTION DEMONSTRATION FLOCKS- WHAT HAVE WE LEARNT?

project are presented. Long-term responses to selection are also discussed. Established along with an unselected control flock (CON) in 1996, the original three selection flocks emphasise use of either measured performance (MPR), professional classer assessment (PCA) or an elite wool or ‘soft rolling skin ’ approach (EWF). A Meat Merino flock was added in 1999 (FM+). All SDFs are outperforming the CON. Commencing with the 2001-drop, considerable divergence between the selection flocks was observed for mean fibre diameter and fleece weight; since that time divergence in mean fibre diameter has not increased, whereas the MPR, EWF and PCA flocks have tended to converge again for fleece weight. Most of the initial advantage in 16-month live weight in the FM+ flock over the CON has been retained in later years, whilst achieving small increases in fleece weight and maintaining a lower mean fibre diameter