Multibreed Angus-Brahman genetic parameters and predictions for nine ultrasound and carcass traits using three genomic-polygenic models and one polygenic model

An abstract of a study by Elzo et al estimating variance components, genetic parameters, EBV, accuracies, and rankings for nine ultrasound and carcass traits in a multibreed Angus-Brahman population using three genomic-polygenic models and one polygenic model (PM) is presented. Additive genetic correlations between pairs of ultrasound and carcass traits were all between -0.31 and 0.81. The highest positive additive genetic correlations were between weight (UW) and ribeye area (UREA), UW and hot carcass weight (HCW), UW and REA, UREA and HCW, UREA and REA, backfat (UFAT) and backfat thickness, and between HCW and REA. The largest negative additive genetic correlations were between UREA and UPIMF, UFAT and SLA, UFAT and HCW, percent intramuscular fat and REA, and between REA and marbling score. High similarity existed among predicted EBV and accuracies from GeneSeek GPF250k SNP set, top 5% SNP, and 5% SNP evenly spread across the genome as well as high-rank correlations for sires, dams, and progenies. This indicated that the two reduced genotype sets were appropriate alternatives to the complete GPF250k set for genomic-polygenic evaluation and selection in this multibreed Angus-Brahman population.