Dataset Information

A bivariate genomic model with additive, dominance and inbreeding depression effects for sire line and three-way crossbred pigs.

ABSTRACT:

Background

Crossbreeding is widely used in pig production because of the benefits of heterosis effects and breed complementarity. Commonly, sire lines are bred for traits such as feed efficiency, growth and meat content, whereas maternal lines are also bred for reproduction and longevity traits, and the resulting three-way crossbred pigs are used for production of meat. The most important genetic basis for heterosis is dominance effects, e.g. removal of inbreeding depression. The aims of this study were to (1) present a modification of a previously developed model with additive, dominance and inbreeding depression genetic effects for analysis of data from a purebred sire line and three-way crossbred pigs; (2) based on this model, present equations for additive genetic variances, additive genetic covariance, and estimated breeding values (EBV) with associated accuracies for purebred and crossbred performances; (3) use the model to analyse four production traits, i.e. ultra-sound recorded backfat thickness (BF), conformation score (CONF), average daily gain (ADG), and feed conversion ratio (FCR), recorded on Danbred Duroc and Danbred Duroc-Landrace-Yorkshire crossbred pigs reared in the same environment; and (4) obtain estimates of genetic parameters, additive genetic correlations between purebred and crossbred performances, and EBV with associated accuracies for purebred and crossbred performances for this data set.

Results

Additive genetic correlations (with associated standard errors) between purebred and crossbred performances were equal to 0.96 (0.07), 0.83 (0.16), 0.75 (0.17), and 0.87 (0.18) for BF, CONF, ADG, and FCR, respectively. For BF, ADG, and FCR, the additive genetic variance was smaller for purebred performance than for crossbred performance, but for CONF the reverse was observed. EBV on Duroc boars were more accurate for purebred performance than for crossbred performance for BF, CONF and FCR, but not for ADG.

Conclusions

Methodological developments led to equations for genetic (co)variances and EBV with associated accuracies for purebred and crossbred performances in a three-way crossbreeding system. As illustrated by the data analysis, these equations may be useful for implementation of genomic selection in this system.

SUBMITTER: Christensen OF

PROVIDER: S-EPMC6701075 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Publications

A bivariate genomic model with additive, dominance and inbreeding depression effects for sire line and three-way crossbred pigs.

Christensen Ole F OF Nielsen Bjarne B Su Guosheng G Xiang Tao T Madsen Per P Ostersen Tage T Velander Ingela I Strathe Anders B AB

Genetics, selection, evolution : GSE 20190819 1

<h4>Background</h4>Crossbreeding is widely used in pig production because of the benefits of heterosis effects and breed complementarity. Commonly, sire lines are bred for traits such as feed efficiency, growth and meat content, whereas maternal lines are also bred for reproduction and longevity traits, and the resulting three-way crossbred pigs are used for production of meat. The most important genetic basis for heterosis is dominance effects, e.g. removal of inbreeding depression. The aims of ...[more]

PMID: 31426753

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Dataset Information

A bivariate genomic model with additive, dominance and inbreeding depression effects for sire line and three-way crossbred pigs.

Background

Results

Conclusions

Publications

A bivariate genomic model with additive, dominance and inbreeding depression effects for sire line and three-way crossbred pigs.

Similar Datasets

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