Merino selection demonstration flocks background and update with 2001 drop hogget results

For a number of years the Merino industry has debated the merits of alternative sheep selection systems. In 1996 the Selection Demonstration Flocks were established to highlight the strengths and weaknesses of alternative sheep selection systems. Three selection demonstration flocks (SDFs) of 200 breeding ewes in each flock were established. A fourth, randomly selected flock of the same size has been maintained as a control group. The SDFs represent: 1. Selection predominantly driven by measurement and performance recording; 2. Selection by visual and tactile appraisal by professional sheep classers, and 3. Selection using the technological package of advocates of the 'soft rolling skin' or 'elite wool flock' approach. A meat Merino line (FM+) has been introduced to demonstrate the attributes of both fibre plus meat traits in conventional Merinos. Results for the fifth (2001) drop from the original flocks and the second drop of the meat Merino line are presented and discussed. The results from selected ewes originating from earlier drops (1997, 1998, 1999 and 2000) are also reported. All selection systems have made significant gains in comparison with the Control flock and after two years of results the FM+ is clearly superior in meat production traits. In previous years (1997, 1998, 1999 and 2000) the rate of genetic improvement has been very similar between selection systems. The 2001 drop provides the first indication of divergence between the selection lines. Further years of results will confirm whether differences are due to selection methods