Figure 2

Short-term rates of genetic gain and inbreeding realised by optimum-contribution selection (OCS) with restrictions. Short-term rates realised by breeding schemes applying OCS with restrictions are at penalties on average relationship that maximised long-term rates of genetic gain, where short and long-term refer to generations 6 to 8 and generations 23 to 25 (approximately). The rates are represented by shaded squares, except for schemes that failed to realise most of the long-term genetic gain realised by OCS without restrictions, namely pre-selection of sires 0.5%, sire multiples 50 and 100, and offspring unknown (empty circles). The plot is overlaid with the short-term response frontier for OCS without restrictions (line with filled circles). The short-term response frontier is short-term rate of genetic gain realised at five penalties plotted as a function of short-term rate of inbreeding. The penalties are 10, 20, 50, 100, and 200. The long-term rate of genetic gain realised by OCS without restrictions was maximised at penalty 50. The rates are means of 100 simulation replicates. The rates were scaled by setting to 100 the long-term rates of genetic gain and inbreeding realised by OCS without restrictions at penalty 50. Rate of genetic gain at 100 is equivalent to 0.215 genetic-standard deviations per time and approximately 0.9 genetic-standard deviations per generation. Rate of inbreeding at 100 is equivalent to 0.0020 per time and approximately 0.008 per generation on the observed scale.