Page 150 - Linear Models for the Prediction of Animal Breeding Values 3rd Edition
P. 150

where q′ is a vector of ones with size equal to the number of TD records for the ith
                i
         cow. The matrices Q′Q and Z′Z are both diagonal and equal. Thus:
            Q′Q = Z′Z = diag[10, 10, 5, 7, 10]
                        −1
            The matrix  A  has been given in Example 4.1. The remaining matrices in the
         MME could be obtained as outlined in earlier chapters. Solving the MME, with the
         solution for the 10th level of HTD effects constrained to zero, give the following results:

         Effects                           Solutions
         HTD
            1                               10.9783
            2                                7.9951
            3                                8.7031
            4                                8.2806
            5                                6.3813
            6                                3.1893
            7                                3.3099
            8                                3.3897
            9                                0.6751
           10                                0.0000
         Fixed regression coefficients
            1                               16.3082
            2                               −0.5227
            3                               −0.1245
            4                                0.5355
            5                               −0.4195
         Animal effect
                                        EBV for daily yield    EBV for 305-day yield
            1                               −0.3300                 −100.6476
            2                               −0.1604                  −48.9242
            3                                0.4904                  149.5718
            4                                0.0043                    1.3203
            5                               −0.2449                  −74.7065
            6                               −0.8367                 −255.2063
            7                                1.1477                  350.0481
            8                                0.3786                  115.4757
         Permanent environmental effects
         Cow                            Solutions for daily yield  Solutions for daily yield
            4                               −0.6156                 −187.7634
            5                               −0.4151                 −126.6150
            6                               −1.6853                 −514.0274
            7                                2.8089                  856.7092
            8                               −0.0928                  −28.3035
         EBV, estimated breeding value.
            The solutions for the fixed regressions are regression coefficients from which
         plots of lactation curves can be obtained. In practice, the fixed regressions are usually
         fitted within group of cows calving in the same season in the same parity and of simi-
         lar age. Thus the curves obtained for various groups of cows are useful for examining
         the influence of different environmental factors on lactation curves. In Example 9.1,


          134                                                             Chapter 9
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