PSIII-A-15 Pregnancy Associated Glycoproteins Effects on Placenta Function, Uterine Remodeling and Attachment of Bovine Conceptuses

Abstract The objective of this study was to evaluate transcriptomic differences in reproductive tissues beef heifers with high vs. low PAG concentrations carrying viable pregnancies during the attachment and early placentation periods. Bos indicus (n=25) were subjected embryo transfer on day 7 IVP embryos, confirmed at slaughter. Heifers harvested days 25 (n=8) 36 (n=8), samples from endometrium (END) trophectoderm (TE) collected for RNA isolation using a commercial extraction kit (QIAGEN; Hilden, Germany). Plasma PAGs determined via validated ELISA females classified groups (6.8±0.7 (n=4) 0.8±0.7 ng/mL D25 15±2.1 (n=5) 4±1.2 (n=3) D36; P< 0.05). An Illumina platform utilized sequencing. Differentially expressed genes between by tissue edge-R package R. Gene ontology analyses revealed down regulation processes associated embryonic placenta development D36 both TE END group. On D36, markers attachment, ECM remodeling invasion significantly upregulated TE, but not pregnancies. differentially groups. In conclusion, peripheral circulation have different gene expression profiles developing conceptus endometrium. results suggested abnormal maternal-conceptus interactions initiated D25, which may resulted poor D36. Disturbances interface could be impairing reaching maternal circulation, since no found This project supported Agriculture Food Research Initiative Competitive Grant no. 2017-67015-26457 USDA National Institute Agriculture.