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					Optimizing age structure in breeding programs
          flock size               180

            first drop    2         rams                      trait mean         4        Kg
            first drop    2         ewes                     Phenotypic SD      0.6       Kg
            mortality     10          %                                  h2     0.35
          mating rate     30      ewes/ram
         weaning rate     90          %
                                                males                         females
          optimize ages here: nr matings         4         years                  4

          Age class Table
   L                      2           3           4                5              6        7
  3.37      Males         2           2           1                1              0        0
  3.37     Females        52          47          42               38             0        0


                                                males      average            females
          proportion retained for breeding      0.02                             0.65
          selection intensity                   2.39            1.48            0.575
          Response/gen                                          0.312             Kg
                                                                                                            im  i f
          generation interval                    3.37              3.37         3.37           R year                 h 2
                                                                                                           Lm  L f
          response per year                                    0.093             Kg


          Note: This assumes selection on phenotype of a single trait, once selected animals stay in the flock
                     In reality we can use EBVs across age classes and have young and old animals compete.
                         8          9     TOTAL
                         0          0       6
                         0          0      180




                               im  i f
                  R year                 h 2 P
                              Lm  L f

elected animals stay in the flock
e young and old animals compete.

				
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posted:8/25/2012
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