Page 102 - Linear Models for the Prediction of Animal Breeding Values 3rd Edition
P. 102

−1
         Then R  = diag(1/77, 1/70) and:
                 ⎡ 0.0311  −0.0186 ⎤
              −1
            G =  ⎢                ⎥
                 ⎣ −0.0186  0.0445 ⎦
            The MME given earlier can easily be set up using the principles discussed so far
         in this chapter. Solving the MME by the direct inverse of the coefficient matrix gave
         the following solutions:


                                             Solutions
                             Effects  Yearling weight (kg)  Fat (kg)

                             HYS
                              1          411.833       193.299
                              2          275.955       205.344
                              3             –          163.315
                             Animal
                              1           −0.472         2.519
                              2           −3.350         0.381
                              3            0.856        −3.208
                              4           −5.142        −3.936
                              5           −4.778        −2.000
                              6            4.778         2.000
                              7            2.177         3.628
                              8           −4.940        −5.251
                              9          −10.234        −3.817
                              10          −8.842        −2.810
                              11           6.932         4.260
                              12          11.568         3.060
                              13           3.029         6.701
                              14          −6.395       −11.485
                              15          −2.797        −1.680
                              16           4.193        10.797
                              17           0.526         0.050

            Selection of dual-purpose sires will be based on some combination of breeding
         value estimates for yearling weight and fat yield. If equal weights were given to yearling
         weight and fat yield, sire 1 would be the best of the three sires, followed by sire 3.


         5.5.2 The multi-trait across-country evaluations (MACE)

         The sire model for MACE was originally proposed by Schaeffer (1994) and involved
         the analysis of the DYD of bulls in different countries as different traits, with the
         number of daughters of a bull used as a weighting factor. The genetic correlations
         among DYDs of bulls in different countries were incorporated. The genetic correla-
         tions accounted for genotype by environment (G × E) interactions and differences in
         national models for genetic evaluations among the countries. The genetic correlations
         among several countries used by Interbull are usually of medium to high value.


          86                                                              Chapter 5
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