Several discoveries have been described recently (5-10 years) about the biology of ovarian follicles (oocyte, cumulus cells and granulosa cells), including new aspects of cellular communication, the control of oocyte maturation and the acquisition of oocyte competence for fertilization and further embryo development. These advances are nourishing assisted reproduction techniques (ART) with new ...

In vitro embryo production (IVEP) is one of the tool to gain rapid genetic improvement in livestock besides its use in conservation of endangered species. IVEP provides necessary starting material for the basic research in animal development, embryo genomics and stem cells. The success of IVEP depends upon several major factors such as quality of oocyte and sperms, type of culture medium, cultu...

Background: Vitrification of oocytes is a fast-freezing technique, which may affect the quality of the human oocyte, and consequently affects the embryo development, pregnancy and birth. The aim of the current study was to investigate the consequence of in-vitro vitrification on maturation status of immature human oocytes, additionally, expression levels of stress, and apoptosis related genes. ...

Oocyte maturation is a final step of gamete development that follows a prolonged period of cell growth within a growing follicle. Unlike oocyte growth that takes several weeks or months, maturation process is a short (hours or days), dynamic process. The period of oocyte maturation varies among species, ranging from 10-13 hours in the mouse (Edwards & Gates, 1959) to 16-24 hours in the cow (Dom...

Oocytes are released from meiotic prophase I arrest through a process termed oocyte maturation. We present here a genetic characterization of oocyte maturation, using C. elegans as a model system. We show that two TIS11 zinc finger-containing proteins, OMA-1 and OMA-2, express specifically in maturing oocytes and function redundantly in oocyte maturation. Oocytes in oma-1;oma-2 mutants initiate...

The canine species has been used as an experimental model for preservation of endangered species. Biotechnologies of reproduction, such as in vitro maturation (IVM), have been used to meet this objective. Several protocols for in vitro embryo production (IVEP) in swine and bovine species have been adapted for canids. However, the highest rate reported for in vitro maturation in canids is only 3...

Energy balance is regulated by ghrelin that is a neuroendocrine modulator. Ghrelin is expressed in reproductive organs. However, the role of ghrelin during in vitro maturation and bovine preimplantational development is limited. The purpose of this study was to determine the expression of ghrelin (GHRL) and its receptor growth hormone secretagogue receptor 1A (GHS-R1A) mRNA expression, and cumu...

Background Oocyte maturity includes nuclear and cytoplasmic maturity, both of which are important for embryo fertilization. The development of oocyte is not limited to the period of follicular growth, and starts from the embryonic period and continues throughout life. In this study, for the purpose of evaluating the effect of the FSH hormone on the expression of genes, GEO access codes for this...

The present studies have been undertaken to investigate the interactions that occur between the nucleus and cytoplasm of ovine oocytes at various stages during meiotic maturation. We report that the nucleus of ovine fully grown dictyate stage oocytes can be efficiently removed by a microsurgical enucleation procedure. It is demonstrated that between the initiation of maturation and germinal ves...

Objective Currently, there is no agreement on the optimal urinary derived human chorionic gonadotropin (u-hCG) dose requirement for initiating final oocyte maturation prior to oocyte collection in in vitro fertilization (IVF), but doses that range from 2500- 15000 IU have been used. We intended to determine whether low dose u-hCG was effective for oocyte maturation in IVF/intracytoplasmic sperm...