Verena Gonzalez Lopez, 2011 - Institut für Tierzucht und Tierhaltung ...

5) Foreign founder gene contributions
For the calculation of genetic contributions of foreign founders to the reference
populations the matrix multiplication X´ZTQ was applied, where X and Z are
incidence matrices for populations and animals. T contains the gene flow from one
generation to the next and is a lower triangular matrix. Accordingly, all diagonal
elements are one and all elements to the right of the diagonal are zero. The matrix Q
assigns the founders to origin herdbook (Kennedy and Trus, 1993).
Software
The software package Pedig from Boichard (2002) was used to calculate measures
of pedigree completeness and marginal contributions of ancestors. All other
parameters have been computed using SAS package or programs in C++ developed
by the author.
Results
Pedigree Completeness
All measures for pedigree completeness were computed considering either the entire
pedigree or pedigrees for each herdbook separately. The percentage of known
ancestors by generation is illustrated in Figure 1.
known ancestors (%)
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
All
SH
BW
B
NRW
LS
generations
Figure 1: Average proportion of known ancestors by generation for each reference
population (animals born between 2006 and 2008): Bavaria (B), Baden-Württemberg (BW),
Lower Saxony (LS), North Rhine-Westphalia and Schleswig-Holstein (SH)) and the entire
pedigree (All).
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