Effects of heterozygosity on performance of purebred and crossbred pigs

Table 2 Models used for each dataset

Model^a	Dataset 1	Dataset 2	Dataset 3
1 Base model	X	X	X
2 Base model + heterozygosity	X	X	X
3 Base model + heterozygosity(breed)^b		X	X
4 Base model + expected heterosis^c			X

Dataset 1 included data from Norwegian Landrace, dataset 2 from Dutch Landrace (breed A), Dutch Large White (breed B), and their F1 cross (breed X), and dataset 3 from a synthetic sire line that was composed of two synthetic sire lines (Lines 1 and 2) that have different genetic origins and have been under selection independently from each other
^a‘Base’ is the base model for each trait from routine evaluations, without any heterozygosity effects, and the remaining models have one heterozygosity effect as indicated
^bFor the synthetic line, breed is proportion of Line 1 (one of the original lines for the synthetic line). This information was available from the pedigree
^cPurebred animals have an expected heterosis of 0%, F1 have an expected heterosis of 100%, backcrosses (Line 1 x F1) have an expected heterosis of 50%, etc. Values were based on existing pedigree data for the synthetic sire line

ISSN: 1297-9686