The stage at which follicle-enclosed cumulus-oocyte complexes achieve developmental competence in primates is unknown. Therefore, studies were designed to characterize the ability of oocytes in small antral follicles present during the menstrual cycle to spontaneously resume meiosis, fertilize, and support early embryo development. Ovaries were removed from adult rhesus monkeys (n = 12) during ...

The aim of this study was to evaluate embryo development of prepubertal goat oocytes fertilised by ICSI according to their diameter. Three experiments were carried out to achieve this objective. In all experiments, oocytes were matured in TCM199 supplemented with hormones, cysteamine and serum for 27 h at 38.5 degrees C. In Experiment 1, we studied the nuclear stage of goat zygotes produced by ...

Some reproduction aspects of the "doctor fish", Cyprinion macrostomum, were examined for the first time from the Tigris River drainage. A total of 316 specimens were caught from Gamasiab River in western Iran, at monthly intervals throughout the year from January to December 2013. Age, sex ratio, fecundity, oocytes diameter, gonado‑somatic (GSI), modified gonado‑somatic (MGSI) and Dobriyal (DI)...

BACKGROUND This study compares the developmental capacity of gametes retrieved from the largest follicle with small follicles of a cohort in controlled ovarian stimulated cycles. MATERIALS AND METHODS This prospective study performed in a private assisted fertilization center included 1016 follicles collected from 96 patients who underwent intra cytoplasmic sperm injection (ICSI). After folli...

Although differences in the quality of oocytes derived from young gilts and adult sows are well documented, evidence concerning gametes of pre-pubertal and cycling gilts is scarce and inconsistent. The aim of this work was to establish whether sexual maturity of gilts affects the quality of their oocytes with the use of the brilliant cresyl blue (BCB) test, oocyte diameter and apoptosis. Ovaria...

Total inhibition of germinal vesicle breakdown (GVBD) was observed in growing pig oocytes (internal diameter 80, 90 and 100 microns) when they were cultured in a medium conditioned by cumulus oocyte complexes (COCs) of fully grown oocytes. In denuded growing oocytes, only partial inhibition was observed. The inhibitory effect was fully reversible. The addition of heparin (300 IU/ml) could overc...

In vitro growth culture systems for oocytes are being developed in several mammalian species. In these growth culture systems, in vitro grown oocytes usually have lower blastocyst formation than in vivo grown oocytes after in vitro fertilization. Furthermore, there have been a few reports that investigated the fertilization ability of in vitro grown oocytes in large animals. The purpose of this...

For developmental competence of porcine embryos in vitro, it is important to improve the culture environment. The present study was performed to evaluate four different culture systems for in vitro matured porcine oocytes following intracytoplasmic sperm injection (ICSI); drop, well and two sizes of the well of the well (WOW) systems (500 and 1,000 microm in diameter). The cleavage rate on Day ...

Using an interspecies microinsemination assay with bovine oocytes, it was examined whether centrosomes of Antarctic minke whale spermatozoa function as the microtubule-organizing centre (MTOC). Bull and rat spermatozoa were used as positive and negative controls, respectively. Vitrified-warmed bovine mature oocytes were subjected to immunostaining against alpha-tubulin 4-6 h after intracytoplas...

The primary objective of this study was to compare expression of maternal transcripts in bovine oocyte populations with differential developmental competence: oocytes from prepubertal and pubertal animals; and oocytes from small (3-4 mm) and large (6-10 mm) follicles from pubertal animals. All transcripts were examined in oocytes prior to and after in vitro maturation (IVM). Genes were selected...