This experiment was performed to clarify relationships between conditions of bovine ovaries and developmental capacity of the follicular oocytes recovered from them and to compare two methods of oocyte collection, aspiration and mincing. Follicular oocytes with surrounding intact, unexpanded cumulus recovered by follicular aspiration or by mincing of tissue from 24 pairs of ovaries were matured...

Follicular fluid is an important environment for oocyte development, yet current knowledge regarding its in vivo oxidant and antioxidant levels remains limited. Examining follicular fluid oxidants and antioxidants will improve understanding of their changes in vivo and contribute to optimisation of in vitro maturation conditions. The aim of the present study was to consider selected markers, na...

BACKGROUND Transplantation of ovarian tissue is, at present, the only clinical option available to restore fertility using cryopreserved ovarian tissue. More than 30 transplantations of cryopreserved tissue have been reported, and six babies have been born, worldwide, following this procedure. Despite these encouraging results, it is essential to optimize the procedure by improving the follicul...

Ischemia is the first mechanism that provokes the loss of follicles in ovarian grafts over the long term. In whole ovarian transplantation, it remains unknown, however, how changes in follicular development are influenced by short-term ischemia. Fresh whole ovarian orthotopic auto-transplantation was performed in rabbits with 45 min ischemia, and the impact of ischemia on follicular survival an...

Improving our understanding of the pattern of follicle development and its manipulation by exogenous hormones in sheep and goats will improve our ability to manipulate their fertility. Repeated ultrasonographic observations of the growth of individual follicles have shown that follicles develop in a wave-like pattern during oestrous cycles, with two or three follicular waves per cycle being mos...

Accurate estimation of the number of ovarian follicles at various stages of development is an important indicator of the process of folliculogenesis in relation to the endocrine signals and paracrine/autocrine mechanisms that control the growth and maturation of the oocytes and their supporting follicular cells. There are 10-fold or greater differences in follicular numbers per ovary at similar...

This study evaluated ovarian activity in late gestation and post-partum in guanacos in captivity. Follicular dynamics was monitored every second day from 40 days before and other 40 after delivery by transrectal sonography and by plasma steroids concentrations. Seven out of eight (87.5%) of gestating females presented ovarian follicular activity under progesterone levels >3 nmol/l with maximum ...

The term “recruitment” has been used to describe the process by which the follicle departs from the resting pool to initiate growth. However, some authors also use this term to describe the engagement of a cohort of antral follicles into further growth. To avoid confusion, McGee and Hsueh suggested that the first situation be called initial recruitment and the latter, cyclic recruitment.[133] C...

Buffaloes play a prominent role in rural livestock production, particularly in Asia. Reproductive efficiency is the primary factor affecting productivity and is hampered in female buffalo by (i) inherent late maturity, (ii) poor estrus expression in summer, (iii) distinct seasonal reproductive patterns, and (iv) prolonged intercalving intervals. Ovarian function is central to these issues; henc...

Although mothers against dpp (MAD) and its related proteins (MADR) are believed to be important components of the cell signaling pathway for the transforming growth factor beta (TGFbeta) superfamily, the presence and regulation of these signaling molecules in ovarian cells by TGFbeta is not known. In the present studies, we have examined the presence of MADR2 and MADR1, two members of the MADR ...