Concentrations of progesterone prior to luteolysis modulates the uterine luminal transcriptome in the subsequent cycle in cattle. Concentrations of progesterone prior to luteolysis modulates the uterine luminal transcriptome in the subsequent cycle in cattle

Sex-steroids concentrations throughout the estrous cycle modulate endometrial function and fertility in cattle. The objective of this study was to compare the post-estrus endometrial transcriptome of cows that were exposed to contrasting pre-estrus concentrations of progesterone before they displayed estrus and ovulated spontaneously. We hypothesized that greater pre-estrus concentration of progesterone alters post-estrus endometrial function even after the display of estrus and spontaneous ovulation. Overall design: Bos indicus-influenced cross-bred beef cows exposed to either high (H) or low (L) pre-estrus concentrations of progesterone. On day -9, the cows assigned to the high progesterone treatment received a new CIDR and 2 mL GnRH i.m. while the cows assigned to low progesterone treatment received a CIDR used twice previously, 5 mL PGF2α i.m. and 2 mL GnRH i.m. Ovarian ultrasonography and blood collections were performed on d -9, d -2, d -0.5, d 0 (observed estrus), d 4, d 7, and d 14 for measurement of ovarian structures, progesterone, and estradiol. Luminal epithelial cells were collected using a cytology brush on d 4, d 7, and d 14 for RNA-sequencing analysis.