BACKGROUND Oocytes are the female gametes which establish the program of life after fertilization. Interactions between oocyte and the surrounding cumulus cells at germinal vesicle (GV) stage are considered essential for proper maturation or 'programming' of oocytes, which is crucial for normal fertilization and embryonic development. However, despite its importance, little is known about the m...

Background: Mammalian oocyte undergoes a series of structural nuclear modulations during maturation in order to obtain full competence to support fertilization and early embryonic development. Microtubules are major cytoskeleton components and have pivotal modulators for chromosomal movement, and it has been shown that partial or immature spindle organization may compromise correct ploidy of th...

BACKGROUND In mammals, the Tribbles family includes widely expressed serine-threonine kinase-like proteins (TRIB1, TRIB2 and TRIB3) that are involved in multiple biological processes including cell proliferation and fatty acid (FA) metabolism. Our recent studies highlighted the importance of FA metabolism in cumulus cells (CC) during oocyte maturation in vertebrates and reported a higher TRIB1 ...

Determining oocyte quality is crucial for successful fertilization and embryonic development, there a serious correlation between live birth rates quality. Parameters such as the regular/irregular formation of cumulus cell layer around oocyte, number layers homogeneity appearance ooplasm are used to determine oocytes be in vitro (IVF) intracytoplasmic sperm injection (ICSI) methods.
 In th...

background: oocyte maturation and subsequent in vitro production (ivp) of embryos are affected by diverse groups of chemicals in maturation medium which are needed for successful mammalian oocyte maturation during which the dramatic cytoplasmic and nuclear reprogramming events take place. this study was designed to evaluate the effects of protein source (fetal bovine serum, fbs, and bovine seru...

BACKGROUND The objective of this study was to investigate whether the steroid hormone(s) secreted from cumulus-oocyte complexes (COCs) is a prerequisite for bovine oocyte maturation and cumulus expansion using aminoglutethimide (AGT), a P450 cholesterol side-chain cleavage inhibitor. METHODS In experiment 1, COCs were cultured in maturation medium with various concentrations of AGT for 22 h t...

Melatonin is a unique multifunctional molecule that mediates reproductive functions in animals. In this study, we investigated the effects of melatonin on bovine parthenogenetic and androgenetic embryonic development, oocyte maturation, the reactive oxygen species (ROS) levels in parthenogenetic and androgenetic embryos and cumulus-oocyte complexes (COCs) hormone secretion with melatonin supple...