Eight calves were derived from differentiated cells of a single adult cow, five from cumulus cells and three from oviductal cells out of 10 embryos transferred to surrogate cows (80 percent success). All calves were visibly normal, but four died at or soon after birth from environmental causes, and postmortem analysis revealed no abnormality. These results show that bovine cumulus and oviductal...

Retinoids, a class of compounds that include retinol and its metabolite, retinoic acid, are absolutely essential for ovarian steroid production, oocyte maturation, and early embryogenesis. Previous studies have detected high concentrations of retinol in bovine large follicles. Further, administration of retinol in vivo and supplementation of retinoic acid during in vitro maturation results in e...

BACKGROUND Deficiencies remain in the ability of in vitro-matured human oocytes to acquire full developmental competence and give rise to a healthy pregnancy. A clear deficiency of current systems utilizing human oocytes has been the absence of cumulus cells. In the present study, a three-dimensional (3D) co-culture system exploiting an extracellular matrix was developed and compared to convent...

The addition of alpha-amanitin to extrafollicular, cumulus-enclosed ovine oocytes at explantation inhibits meiotic maturation and prevents many of the changes in protein synthesis that normally accompany maturation. By contrast, these inhibitory effects are considerably reduced by either delaying the addition of the drug for 1-4 h or by denuding the oocytes of all associated cumulus cells at th...

Oocyte maturation is a key issue of current animal biotechnology. This study was designed to examine the morphodynamics of the cumulus-oocyte association during oocyte maturation. Porcine cumulus-oocyte complexes were recovered from slaughterhouse ovaries; matured in vitro for 0, 24, 36, and 44 h; and evaluated by scanning electron microscopy either combined or not combined with the osmium-dime...

The cumulus-oocyte complex (COC) is an oocyte surrounded by specialized granulosa cells, called cumulus cells. cells surrounding the ensure healthy and embryo development. maturity of COCs at retrieval may be used as indicator to predict outcome assisted reproductive technology (ART). Segmenting a preliminary step in many image processing pipelines evaluate maturity. However, acquiring well-ann...

Background: For several years, mammalian cloning by splitting an early embryo or nuclear transfer into oocytes method has been successfully performed. Cloning is now also possible using adult somatic cells. Although it has now been 15 years since the first cloned mammals were generated from somatic cells using nuclear transfer (NT), the success rate for producing live offspring by cloning is lo...

Background: The hyaluronidases are the enzymes hydrolyze β-1, 4 glycosidic linkage of hyaluronan. Hyaluronan is a polymer consisting of a repeating disaccharide unit found in cumulus ovuforus complex, semen liquid and other tissue. Addition to hydrolyzing the hyaluronan, hyaluronidase can penetrate through the cumulus cells layer that surrounds the oocyte, thus it terms spreading factor. Moreov...

Most studies have considered the negative influence of obesity on fertility in both genders. In the present study, we assessed mitochondrial activity expressed as the mitochondrial potential index (MPI) in cumulus cells from obese women and women with a normal body mass index (BMI) during assisted reproductive therapy. The results revealed a significant reduction of MPI with increased body mass...

BACKGROUND Serum AMH is declining with age and is highly associated with ovarian follicular reserve and disordered folliculogenesis. However, the precise role of AMH in the process of human follicular aging has still to be determined. AIM This study investigates AMH level in the follicular fluid (FF) and mRNA expression pattern in cumulus and mural granulosa cells of human ovarian follicles i...