PSIII-4 Late-Breaking: Genetic Marker Association Study of Heifer Pregnancy in Red Angus Cattle

Abstract Heifer pregnancy (HPG) is lowly heritable, yet economically relevant in beef cattle production systems. Hence, identifying single nucleotide polymorphisms (SNP) associated with phenotype could increase the amount of information used genetic evaluation trait. Using RNA-sequence data from lactating Holstein cows, a set SNP (n = 69) were discovered among embryo mortality conceptuses (Conceptus-SNP) maternal recognition on day 16 after artificial insemination (AI). To further study these SNP, our objective was to conduct analyses identify markers HPG Red Angus. Phenotypic records and genotypes provided by Angus Association America (RAAA). For phenotypes, total 59,387 records, June 2022 RAAA evaluation, analysis. genotype data, 47,860 panel (excluding X-chromosome) formed combining historical (96,162 animals genotypes) whole genome sequence 30 prominent AI sires. Markers mapped ARS-UCD1.2 bovine reference then imputed using findhap software. A subset 2,169 SNP; Conceptus-SNP multi-breed selected reduced [MSRP]) extracted file. PLINK software, quality control procedure performed so that call rate < 0.9 removed. marker removed if: it had minor allele frequency 0.01, not Hardy–Weinberg equilibrium (P 0.00001), or high linkage disequilibrium (r2 > 0.95). The final file contained 96,667 2,137 SNP. Bayes Cπ single-step super hybrid model (π 0.99), BOLT software package, estimate marker’s posterior probability inclusion (PPI), significance criterion predicting HPG. PPI calculated as average four different Gibbs sampling chains 75,000 iterations included 5,000 burn-in. rs42576394 (18:60583784) rs42942055 (14:34249373) 25.5 7.1%, respectively; suggesting association None detectable HPG; however, may be much more informative for trait stayability. Such would measured mature cows potentially similar which discovered.