Page 109 - Linear Models for the Prediction of Animal Breeding Values 3rd Edition
P. 109

The matrices of weights (W ) using Eqn 5.19 are:
                                    i
                 ⎛  0 55884 − .       − 1 ⎛  0 4620 −  0 62436 ⎞  ⎛  0 4229 − 0 3614⎞
                             0 62436⎞
                                                   .
                    .
                                                                          .
                                                                 .
                                           .
            W =                                             =
              1  ⎜ ⎝ − 0 62436  0 99693⎠ ⎟  ⎜ ⎝ − 0.662436 0 99693 ⎠ ⎟  ⎜ ⎝ − 0 3614  1 0000⎠ ⎟
                                                   .
                              .
                    .
                                                                          .
                                                                 .
        and:
                               0 62436⎞
                 ⎛  0 55884   − .       − 1 ⎛ 0 09685  0⎞  ⎛ 0 0 5771 0⎞
                    .
                                           .
                                                           .
            W =                                        =
              2  ⎜ ⎝ − 0 62436  0 99693⎠ ⎟  ⎜ ⎝ 0   0⎠ ⎟  ⎜ ⎝ 0 3614  0⎠ ⎟
                                                           .
                                .
                    .
        Therefore the vector proofs of bull 3 are:
            ⎛  ˆ a ⎞  ⎛  . 2 68225⎞  ⎛ 11 .9971⎞  ⎛  . 113343⎞  ⎛ 6 9235⎞  ⎛ 8 058⎞
                                                            .
                                                                      .
              31
            ⎜ ⎝  ˆ a ⎠ ⎟  = W 1 ⎜ ⎝  . 1 63375⎠ ⎟  + W 2 ⎜ ⎝  0  ⎟ ⎠  =  ⎜ ⎝ 0 6644⎠ ⎟  +  ⎜ ⎝ 4 3358⎠ ⎟  =  ⎜ ⎝ 5 000⎠ ⎟
                                                  .
                                                                      .
                                                            .
              32
        The contribution from the DRP of bull 3 in country 1 accounts for over 85% of the
        MACE proof in both countries, although the bull has no DRP in country 2. Thus,
        with only 20 daughters, parental contribution was not very large, although in gen-
        eral, parental contributions will be influenced by the heritability of the traits in both
        countries and the genetic correlation between them.
            When a bull has a proof only in country i and not in j, its proof in country j can
        be obtained (Mrode and Swanson, 1999) as:
            a = PA  − (g /g )(aˆ  − PA )                                    (5.21)
            ˆ
             j    j   ij  ii  i  i
        where g  is the genetic variance in country i and g  the genetic covariance between
               ii                                    ij
        countries i and j. Therefore, if interest was only in calculating the proof of bull 3 in
        country 2, it can be obtained from the above equation as:
            a  = 1.63375 − (12.839/20.5)(8.059 − 2.68225) = 5.001
            ˆ
             32
                                                                           ˆ
        Equation 5.21 can be derived from Eqn 5.18 as follows. The equation for a  from
                                                                           32
        Eqn 5.18 is:
                        22
                                                  21
              22
            (g a )aˆ  = g a (aˆ   + 0.5(a ˆ   + g ˆ  ) + g a (a ˆ   + 0.5(a ˆ   + g ˆ  )
                bull  32  par  sire2  mgs2  mgd2    par  sire1  mgs1  mgd1
                          21
                       + (g a )aˆ
                            bull  31
        where a ˆ  , a ˆ   and g ˆ   are the proofs for the sire, MGS and solution for the MGD
               sirej  mgsj  mgdj
                                   ii                        −1
                                                                      bull  par
        in country j, respectively, and g  are the inverse elements of G . Since a   = 2a  for
                                                  −1
        bull 3, multiplying the above equation by (2a )  gives:
                                                par
                                       21
                    22
             22
                              21
            g aˆ  = g (PA ) + g (PA ) − g aˆ
                32       2        1      31
                              21
             22
                    22
            g a  = g (PA ) − g (a  − PA )
               ˆ
                                ˆ
                32       2       31    1
                          22
                       21
            ˆ
            a  = PA  − g /g (aˆ  − PA )
             32    2          31    1
            a  = PA  − g /g (aˆ  − PA )
            ˆ
             32    2   21  22  31   1
        Thus the proof of a bull in country j is dependent on the parent average of the
        bull in country j and the Mendelian sampling of the bull in the ith country.
            Partitioning the proof of bull 2 with records in both countries and a
        maternal grandson (bull 3) is as follows. The country deviations for bull 2 in
        both countries are:
            CD  = y  − m  = 9.9717 − 7.268 = 2.7037
               21   21   1
        Multivariate Animal Models                                            93
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