A second model also included the fixed
effects of genetic group. The use of genetic groups
resulted in means of selection efficiency and correlation
of 70.4 to 97.1% and 0.51 to 0.94 for WW, 85.8 to
98.8% and 0.82 to 0.98 for SC, and 85.1 to 98.6% and
0.74 to 0.97 for MUSC, respectively. High selection
efficiencies were observed for year of birth and breed
composition strategies. The maximum absolute difference
in annual genetic gain estimated through the
use of complete genealogy and genetic groups were
0.38 kg for WW, 0.02 cm for SC, and 0.01 for MUSC,
with lower differences obtained when year of birth
was adopted as a genetic group criterion. Grouping
strategy must consider selection decisions and the
number of genetic groups formed, in the way that
genetic groups represent the genetic differences in
population and allow an adequate prediction of EBV.