Endometrial surface adaptive changes during first half of pregnancy in mares

s / Journal of Equine Veterinary Science 34 (2014) 205 205 Table 1). At 149 days of pregnancy the endometrium appeared wrinkled and a novel structure appeared, presumed to be microcaruncles, cavities that receive the microcotyledons from the chorioallantoic membrane. The borders of the cells were barely appreciable, and some secreted vesicles were still visible, but histotrophe was not (Figure 1F, Table 1). Fig. 1. Scanning electron micrograph of endometrium of a mare A) at 21 days of pregnancy, B) at 30 days, C) at 35 days of pregnancy and D) at 62 days of pregnancy showing: protruded microvillus secretory cells (stars), flattened secretory cells on top of folds (asterisk), ciliated cells (arrows), eroded secretory cells (square), glandular opening (G) with secreted vesicle blebs (arrow head) and histotrophe (H) accumulated on troughs. E) Micrograph at 119 days of pregnancy, with irregularly orientated ridges separated by grooves. F) Micrograph at 149 days of pregnancy, showing a wrinkled aspect of endometrium, glandular opening (G) and microcaruncle formation (arrows).