Genomic selection is becoming a routine application in dairy cattle breeding for the advantages it gives in terms of reduced generation interval, increased accuracy and increased selection intensity. Effectiveness and practical implementation of genomic selection on pig breeds is not clear yet due to biological and technically derived differences between pig and cattle breeding (e.g. much shorter generation interval, large litter size, reduced number of semen doses produced per boar in A.I.). However, a few preliminary North European simulation studies have reported that some advantage from genomic selection might also be expected in pigs. However, studies based on North European vision of pig breeding do not take into account the peculiarities of the Italian heavy pig breeding system. Italian pig selection is based on a sib-testing scheme in which 2 full sisters and 1 full castrated brother from the same litter of the candidate boar are performance tested. This scheme opens a wide range of different genotyping strategies to be evaluated. To this aim, a pig breeding population with a 18 chromosome genome marked with 60K bi-allelic single nucleotide polymorphisms and several segregating QTLs was simulated by using the software QMSim. The population was genetically selected over 25 generations based on BLUP estimated breeding values (EBV) for a trait with heritability of 0.40. Culling was based on EBV both in sires and dams. Different genotyping strategies as well as different methods of predicting genomic breeding values (GBLUP, Bayes or Single Step) were compared. Accuracies of genetic values were calculated as correlation with true breeding values. Considering the simulated scenarios, the introduction of genomic evaluations might increase accuracy levels both in young piglets and in selected reproducers. In particular, the choice of the male candidate would be more effective. Other simulations are under way to evaluate if genomic selection could actually give economic advantages to the Italian heavy pig breeding industry.
Genomic selection in Italian heavy pigs: a simulation study / Samorè A.B.; Buttazzoni L.; Gallo M.; Russo V.; Fontanesi L.. - In: ITALIAN JOURNAL OF ANIMAL SCIENCE. - ISSN 1594-4077. - ELETTRONICO. - 12:Suppl. 1(2013), pp. 5-5.
Genomic selection in Italian heavy pigs: a simulation study
SAMORE', ANTONIA BIANCA;RUSSO, VINCENZO;FONTANESI, LUCA
2013
Abstract
Genomic selection is becoming a routine application in dairy cattle breeding for the advantages it gives in terms of reduced generation interval, increased accuracy and increased selection intensity. Effectiveness and practical implementation of genomic selection on pig breeds is not clear yet due to biological and technically derived differences between pig and cattle breeding (e.g. much shorter generation interval, large litter size, reduced number of semen doses produced per boar in A.I.). However, a few preliminary North European simulation studies have reported that some advantage from genomic selection might also be expected in pigs. However, studies based on North European vision of pig breeding do not take into account the peculiarities of the Italian heavy pig breeding system. Italian pig selection is based on a sib-testing scheme in which 2 full sisters and 1 full castrated brother from the same litter of the candidate boar are performance tested. This scheme opens a wide range of different genotyping strategies to be evaluated. To this aim, a pig breeding population with a 18 chromosome genome marked with 60K bi-allelic single nucleotide polymorphisms and several segregating QTLs was simulated by using the software QMSim. The population was genetically selected over 25 generations based on BLUP estimated breeding values (EBV) for a trait with heritability of 0.40. Culling was based on EBV both in sires and dams. Different genotyping strategies as well as different methods of predicting genomic breeding values (GBLUP, Bayes or Single Step) were compared. Accuracies of genetic values were calculated as correlation with true breeding values. Considering the simulated scenarios, the introduction of genomic evaluations might increase accuracy levels both in young piglets and in selected reproducers. In particular, the choice of the male candidate would be more effective. Other simulations are under way to evaluate if genomic selection could actually give economic advantages to the Italian heavy pig breeding industry.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
