Uterine Influences on Conceptus Development in Fertility-Classified Animals

This study relates to pregnancy outcome after assisted reproduction of fertility-classified cattle. The aim is to investigate how the uterine environment impacts and programs conceptus survival and development. The study found that ripple effects of dysregulated conceptus-endometrial interactions elicit post-elongation pregnancy loss in subfertile animals during the implantation period. Heifer cows classified as high fertile (HF), subfertile (SF), or infertile (IF) were investigated. The RNA-seq analysis was performed for endometrium samples at day 17 of pregnancy. For comparison, non-pregnant cows were included in the analysis. RNA from conceptus of HF and SF pregnant animals (day 17) were also included in the RNA-seq analysis. A total of 25 endometrium samples (5 non-pregnant of each fertilty group, 5 pregnant HF, and 5 pregnant SF) and 27 conceptus samples (10 SF and 17 HF) were used in the RNA-seq analysis.