Quantitative analysis of changes in endometrial gland morphology during the bovine oestrous cycle and their association with progesterone levels

Abstract

This study describes a digital technique for uterine morphometry and its application to endometrial structure during the bovine oestrous cycle. Neither the number nor the size of uterine gland ducts changed during the cycle but a reduction in total endometrial area from days 0 to 8 after oestrus led to an increase in the proportion of the endometrium occupied by gland ducts (gland duct density). This effect on day 8 was maintained to day 16. When endometrial morphology was related to circulating progesterone concentrations on days 5 and 8 of the luteal phase, no relationships were found on day 5, but on day 8, a high progesterone concentration was associated with an increased number of gland ducts. Furthermore, in animals slaughtered on day 8, a high progesterone concentration on day 5 was associated with decreased gland duct size, though a simultaneous decrease in endometrial area led to an increase in gland duct density. The results suggest that contrary to expectation, endometrial glands do not grow and regress during the oestrous cycle, although cyclic changes in endometrial area controlled by progesterone lead to changes in gland duct density.

Evaluation and comparison of the antifertility potential activity and adverse effects of Trigonella foenum-graecum seeds and combined oral contraceptive pills in female rats

“…21 While in COCPs1 treated group immediately after stopping the treatment was found to be 8.16 and in COCPs2 treated group after 15 days of stopping the treatment was be to found 16.16. The glands number in both groups COCPs1 and COCPs2 treated group reduced which a remarkable sign of endometrial atrophy and it is also a sign that that even after stop taking the contraceptive pills the side effect will be in the body.…”

Exogenous hormonal manipulation to increase reproductive efficiency in dairy cows

“…It is thought that lactation, with associated increases in DM intake, enhances the catabolism of progesterone by the splanchnic tissues, primarily the liver WILTBANK et al, 2011). A reduction in progesterone could limit proper uterine priming and conceptus development (CARTER et al, 2008;, thereby reducing P/AI in dairy cows (PARR et al, 2012;STRONGE et al, 2005).…”

“…Furthermore, the changes in the present study mimic increases in progesterone associated with higher fertility in heifers FORDE et al, 2009). Concentration of progesterone during early to mid-diestrus was associated with changes in endometrial gland ducts (WANG et al, 2007), that likely increase the supply of nutrients for the developing conceptus and accommodate changes for subsequent placentation (SPENCER et al, 2007). The changes in endometrial gene expression and consequent alterations in glandular function and histotroph supply were thought to mediate the advancements in conceptus elongation and changes in embryonic gene expression when heifers had increased concentrations of progesterone (CARTER et al, 2008(CARTER et al, , 2010.…”

“…Thus, similar to GnRH-based programs, protocols using E2/P4 may have problems with correct synchronization of the follicular wave at the beginning of the program and synchronized ovulation at the end of the program. Critical features of FTAI protocols that need to be optimized include: follicular wave emergence and growth (WILTBANK et al, 2011), concentration of P4 during follicular growth WILTBANK et al, 2014), complete lysis of the CL at the time of AI PEREIRA et al, 2013b;WILTBANK et al, 2014), and size of the ovulatory follicle (WILTBANK et al, 2011;PEREIRA et al, 2013aPEREIRA et al, , 2014.…”

“…It is thought that inadequate progesterone concentrations during early development of the conceptus might be one of the reasons for reduced fertility observed in high-producing dairy cows (WILTBANK et al, 2011), in part because catabolism of steroids increases with increased feed intake associated with high production WILTBANK et al, 2011). In fact, supplemental progesterone after AI from an exogenous source (STEVENSON et al, 2007;WILTBANK et al, 2011) Timed AI protocols result in variable sizes of ovulatory follicles in dairy cows SANTOS et al, 2010). Induction of ovulation of small follicles resulted in reduced P/AI in beef (PERRY et al, 2005) and dairy cows , and increased risk of pregnancy loss (PERRY et al, 2005).…”