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The effects of pedigree errors or selection of data on three methods of estimating breeding values for litter size, backfat and average daily gain in swine
Abstract
Estimated breeding value (EBV) was calculated based on either individual phenotype (SP), an index of individual phenotype and full- and half-sib family averages (SI) or Best Linear Unbiased Prediction (BLUP). EBVs were calculated using correct data or data having either pedigree errors or truncation of the poorest records. Traits considered were: litter size (LS), backfat (BF) and average daily gain (ADG). When data were correct, BLUP resulted in an advantage in expected genetic gain over SP of 22, 7.2 or 30.8% for LS, BF and ADG, respectively, and over SI of 9.6, 3.8 or 21.4% for LS, BF and ADG, respectively. Selection of data did reduce genetic gain per generation for each trait. If the poorest 20% of the data were deleted prior to analysis each generation, genetic gain using SI was reduced by 3.7, 3.2 or 0% for LS, ADG or BF, respectively. Genetic gain using BLUP was reduced by 5.4% for LS, 7.5% for ADG and 1.9% for BF. In comparison to SP, the method unaffected by selection of data, the advantage of BLUP in rate of genetic gain with deletion of 20% of the records was 15.3% for LS, 21% for ADG and 5.2% for BF. When sire and dam pedigrees were incorrect for 20% of the pigs in each generation, genetic gain using SI was reduced by 7% for LS, 6.5% for ADG and 2.5% for BF. Genetic gain using BLUP on records with 20% pedigree errors was reduced by 9.3%, 12.5% and 3.2% for LS, ADG and BF, respectively. These results suggest that, although BLUP is affected to a greater degree by pedigree errors or selection of data than SP or SI, selection of swine using BLUP on field data would improve response to selection over the use of SP or SI.
Subject Area
Genetics|Livestock
Recommended Citation
Long, Thomas Edward, "The effects of pedigree errors or selection of data on three methods of estimating breeding values for litter size, backfat and average daily gain in swine" (1989). ETD collection for University of Nebraska-Lincoln. AAI8918553.
https://digitalcommons.unl.edu/dissertations/AAI8918553