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Genetic progress was estimated in the major breed groups of the Sheep Genetics database as a means of monitoring changes in the productivity of sheep enterprises. There has been substantial improvement in productivity between 1990 and 2005 based on representative breeding objectives for each breed, ranging from $10 per ewe for Border Leicesters (0.7 standard deviations of the breeding objective) to $17 per ewe for Terminal Sire breeds (2.9 standard deviations). Rates of progress have increased significantly since 2000 for the Terminal Sire, Border Leicester and Coopworth breeds, while Merinos have maintained a relatively constant and favourable rate of progress over the whole time period. Compared to simple breeding programs simulated for each breed group, Terminal Sires are exceeding the simulated potential rate of gain, Border Leicesters and Coopworths are approaching the potential gain, while Merinos are achieving only one third of the potential gain. |
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