Potential of preimplantation genomic selection for carcass traits in Japanese Black cattle

Abstract

Preimplantation genomic selection using genomic estimated breeding values (GEBVs) based on single nucleotide polymorphism (SNP) genotypes is expected to accelerate genetic improvement in cattle. To develop a preimplantation genomic selection system for carcass traits in Japanese Black cattle, we investigated the accuracy of genomic evaluation of carcass traits using biopsied embryonic cells (Experiment 1); we also performed an empirical evaluation for embryo transfer (ET) of vitrified GEBV-evaluated blastocysts to assess the efficiency of the preimplantation genomic selection system (Experiment 2). In Experiment 1, the mean call rate for SNP genotyping using approximately 15 biopsied cells was 98.1 ± 0.3%, whereas that for approximately 5 biopsied cells was 91.5 ± 2.4%. The mean concordance rate for called genotypes between ~15-cell biopsies and the corresponding biopsied embryos was 99.9 ± 0.02%. The GEBVs for carcass weight, ribeye area, and marbling score calculated from ~15-cell biopsies closely matched those from the corresponding calves produced by ET. In Experiment 2, a total of 208 in vivo blastocysts were biopsied (~15-cell) and the biopsied cells were processed for SNP genotyping, where 88.5% of the samples were found to be suitable for GEBV calculation. Large variations in GEBVs for carcass traits were observed among full-sib embryos and, among the embryos, some presented higher GEBVs for ribeye area and marbling score than their parents. The conception rate following ET of vitrified GEBV-evaluated blastocysts was 41.9% (13/31). These findings suggest the possible application of preimplantation genomic selection for carcass traits in Japanese Black cattle.

Preimplantation Genetic Testing for Aneuploidy Improves Live Birth Rates with In Vitro Produced Bovine Embryos: A Blind Retrospective Study

“…The high demand for dairy and beef products has spurred the implementation of new approaches in IVP, combining the most recent advances in embryology with genomics and bioinformatics. Currently, around one million IVP cattle embryos are transferred annually, with a growing proportion screened for genomic estimated breeding values (GEBVs) before embryo transfer (ET) [2,3]. The idea of employing a genomic evaluation to estimate breeding values of individual animals is not new [4].…”

Potential of preimplantation genomic selection using the blastomere separation technique in bovine <i>in vitro</i> fertilized embryos

“…We confirmed that the production efficiency of monozygotic twin embryos in the current study compares favorably with previous reports. Additionally, we observed that the rate at which a couple of blastomeres developed into a blastocyst and to a ≥ 16-cell stage embryo (thought to be applicable for reliable SNP genotyping [5]) at day seven was 73.6% (78/106), which was not different from the rate of blastocyst formation at day seven in the control group (81.3%, 87/107). This result indicates that BS treatment does not reduce the efficiency of the preimplantation genomic selection system compared to the microblade biopsy approach using intact blastocysts.…”

“…6 was 99.3%. We reported that the genomic estimated breeding values (GEBVs) for carcass traits, such as carcass weight, ribeye area, and marbling, calculated from the embryonic biopsied cells (approximately 15 cells) with call rates of 98.5-99.3% closely matched those from the corresponding calves produced by embryo transfer in Japanese Black cattle [5]. Furthermore, in a study on dairy cattle, it was observed that the correlation between the GEBV of kg of milk protein (based on 305-day production) in embryonic biopsied cells and the corresponding calves was high (r 2 = 0.95) when samples with a call rate >85% were used [11].…”

“…In Holstein and Japanese Black cattle, a genomic selection system has been established and introduced for the prediction of economically important traits, such as lactation or carcass characteristics [2][3][4]. Additionally, we developed a preimplantation genomic selection system that combines genomic selection with multiple ovulation and embryo transfer (MOET) and preimplantation genetic testing [5]. This system is expected to render cattle breeding more efficient through the selective production of genetically superior animals.…”

Performance of using opposing homozygotes for paternity testing in Japanese Black cattle

“…Genomic prediction should further increase the rate of genetic improvement in this breed (e.g. Fujii et al, 2019;Miyake & Ogawa, 2021;Ogawa, Matsuda, Taniguchi, Watanabe, Kitamura, et al, 2016;Onogi et al, 2014;Watanabe, 2016). Recently, genomic prediction for traits other than carcass traits (e.g.…”