Background:One of the biggest challenges in the swine industry is to increase female reproductive efficiency.Recently,vulva score categories(VSC),assessed prior to puberty,has been proposed as an indicator trait of ef...Background:One of the biggest challenges in the swine industry is to increase female reproductive efficiency.Recently,vulva score categories(VSC),assessed prior to puberty,has been proposed as an indicator trait of efficient reproductive performance in sows.The objective of this study was to validate the use of VSC as an indicator trait for reproductive performance,and to perform genetic and genomic analyses for VSC.Methods:The phenotypic relationship of VSC,using a three-point scale:small(VSC-S),medium(VSC-M),and large(VSC-L),on reproductive performance was evaluated on three farms.VSC was measured at 15 weeks of age,for farms 1 and 2,and at 14 weeks of age for farm 3 on 3981 Yorkshire gilts,in which 1083 had genotypes(~50 K SNPs).Genetic parameters for VSC with reproductive traits were estimated using ssGBLUP.A Genome-wide association study(GWAS)for VSC was performed using BayesB.Results:For the phenotypic analysis of VSC across datasets,differences in performance were identified there was a significant effect(P≤0.05)for the interaction between Farm and VSC for total number dead(TND),and a trend(P<0.10)for total number born(TNB).There were significant(P≤0.05)pre-defined contrasts of VSC-S versus VSC-M+L on TNB,number born alive(NBA),TND,number of stillborn(NSB),and number of mummies(MUM).Heritability estimates for VSC as a categorical trait(VSCc)and a quantitative trait(VSCq)were 0.40±0.02 and 0.83±0.02,respectively,for across farm,0.13±0.07 and 0.20±0.10,respectively,for Farm1,0.07±0.07 and 0.09±0.09,respectively,for Farm2,and 0.20±0.03 and 0.34±0.05,respectively,for Farm3.For across farms,favorable genetic correlations estimates were found for TNB(0.28±0.19)and NBA(0.26±0.17).Within farms,moderate genetic correlations between VSC with reproductive traits were found for TNB(0.61±0.47)and MUM(0.69±0.47)for farm 1,for number of services until first farrow(NS;0.69±0.38)and unique service with successful first farrow(SFS;−0.71±0.38)for farm 3.Multiple genomic regions associated with VSCc were identified.Of these,a QTL located on chromosome 3 at 33–34Mb accounted for about 7.1%of the genetic variance for VSCc and VSCq.This region harbors the gene PRM1 that has been associated with early embryonic development in pigs.Conclusions:The results support potential of VSC for improved reproductive efficiency on first-parity performance,but the results might depend on the interaction between environmental factors and VSC,as well as potentially additive genetics.展开更多
The swine industry in China is a thriving and evolving industry that has shown phenomenal growth over the past 10 years. To insure long term success and viability in a worldwide competitive industry such as pork, ther...The swine industry in China is a thriving and evolving industry that has shown phenomenal growth over the past 10 years. To insure long term success and viability in a worldwide competitive industry such as pork, there is need for a National Swine Genetic Improvement Program. This program needs to draw on expertise and technology from across the world for its development, but it should be based on the structure of the pig industry in China and be led by Chinese scientists, administrators and producers. National Genetic Improvement requires more than just technology. A successful program of national genetic improvement will require cooperation from the industry and the government. The support for the university system is essential for the success of the pig industry. The university system has a vital role on education (of students, faculty, producers and consumers) as well as research and technology transfer. The government could also have a role in supporting the central test stations and AI stations across the country. An accurate and comprehensive pedigree maintenance system is essential to genetic improvement. And it will be vitally important to be active in the importation of new genetics to sample other populations.展开更多
文摘Background:One of the biggest challenges in the swine industry is to increase female reproductive efficiency.Recently,vulva score categories(VSC),assessed prior to puberty,has been proposed as an indicator trait of efficient reproductive performance in sows.The objective of this study was to validate the use of VSC as an indicator trait for reproductive performance,and to perform genetic and genomic analyses for VSC.Methods:The phenotypic relationship of VSC,using a three-point scale:small(VSC-S),medium(VSC-M),and large(VSC-L),on reproductive performance was evaluated on three farms.VSC was measured at 15 weeks of age,for farms 1 and 2,and at 14 weeks of age for farm 3 on 3981 Yorkshire gilts,in which 1083 had genotypes(~50 K SNPs).Genetic parameters for VSC with reproductive traits were estimated using ssGBLUP.A Genome-wide association study(GWAS)for VSC was performed using BayesB.Results:For the phenotypic analysis of VSC across datasets,differences in performance were identified there was a significant effect(P≤0.05)for the interaction between Farm and VSC for total number dead(TND),and a trend(P<0.10)for total number born(TNB).There were significant(P≤0.05)pre-defined contrasts of VSC-S versus VSC-M+L on TNB,number born alive(NBA),TND,number of stillborn(NSB),and number of mummies(MUM).Heritability estimates for VSC as a categorical trait(VSCc)and a quantitative trait(VSCq)were 0.40±0.02 and 0.83±0.02,respectively,for across farm,0.13±0.07 and 0.20±0.10,respectively,for Farm1,0.07±0.07 and 0.09±0.09,respectively,for Farm2,and 0.20±0.03 and 0.34±0.05,respectively,for Farm3.For across farms,favorable genetic correlations estimates were found for TNB(0.28±0.19)and NBA(0.26±0.17).Within farms,moderate genetic correlations between VSC with reproductive traits were found for TNB(0.61±0.47)and MUM(0.69±0.47)for farm 1,for number of services until first farrow(NS;0.69±0.38)and unique service with successful first farrow(SFS;−0.71±0.38)for farm 3.Multiple genomic regions associated with VSCc were identified.Of these,a QTL located on chromosome 3 at 33–34Mb accounted for about 7.1%of the genetic variance for VSCc and VSCq.This region harbors the gene PRM1 that has been associated with early embryonic development in pigs.Conclusions:The results support potential of VSC for improved reproductive efficiency on first-parity performance,but the results might depend on the interaction between environmental factors and VSC,as well as potentially additive genetics.
文摘The swine industry in China is a thriving and evolving industry that has shown phenomenal growth over the past 10 years. To insure long term success and viability in a worldwide competitive industry such as pork, there is need for a National Swine Genetic Improvement Program. This program needs to draw on expertise and technology from across the world for its development, but it should be based on the structure of the pig industry in China and be led by Chinese scientists, administrators and producers. National Genetic Improvement requires more than just technology. A successful program of national genetic improvement will require cooperation from the industry and the government. The support for the university system is essential for the success of the pig industry. The university system has a vital role on education (of students, faculty, producers and consumers) as well as research and technology transfer. The government could also have a role in supporting the central test stations and AI stations across the country. An accurate and comprehensive pedigree maintenance system is essential to genetic improvement. And it will be vitally important to be active in the importation of new genetics to sample other populations.
