Mouse oocytes were placed in Hepes-T6 containing 7.5 μg/ml cytochalasin B and 5μg/ml Hoechst prior to enucleation, and enucleation was performed on oocytes using the manipulator. The oocyte held in place by gentle suction of a holding pipette (oocyte diameter approx.70 μm). The metaphase spindle (arrow) is aspirated into an enucleation pipette (1).

There has been no culture system that supports the growth of bovine oocytes for more than 2 weeks. In the present study, bovine secondary follicles were cultured for 4 weeks, and the effects of supplemented protein components and FSH in the culture medium on the growth of the oocytes were examined. The effect of vitrification of secondary follicles on the subsequent oocyte growth was also exami...

Oocytes were removed from follicles 5-30 mm in diameter. The germinal vesicle was present in 69.6% (23/33) of the oocytes at the start of culture, but after 20-24 and 40 h 70.5% (12/17) and 68.2% (43/63) of the oocytes were in metaphase I and metaphase II with first polar body extruded, respectively.

We previously reported that xenografted bovine secondary follicles developed to the antral stage in severe combined immunodeficient (SCID) mice. In the present study, bovine secondary follicles 100-240 microm in diameter were xenografted under the kidney capsules of female SCID mice for 6 and 8 weeks, and we examined the oocytes' fertilization and developmental abilities. Bovine follicles devel...

Bovine ovaries offer a large pool of oocytes that could be used for in vitro production of embryos of genetically valuable animals. The effects of in vitro growth (IVG) culture duration (10, 12, and 14 days) on the viability and growth of bovine oocytes derived from early antral follicles (0.5-1 mm diameter) in this study. In addition, the effect of pre-IVM culture with phosphodiesterase inhibi...

OBJECTIVE To test the developmental competence of oocytes in a nonhCG-triggered in vitro maturation (IVM) system when oocyte-cumulus complexes (OCC) are retrieved from antral follicles with a diameter of <6 mm. DESIGN Prospective cohort study. SETTING Tertiary university-based referral center. PATIENT(S) From January 2010 to September 2011, 121 patients with polycystic ovaries/polycystic ...

The aim of this work was to evaluate the relationship between follicular size at the time of oocyte retrieval, and the subsequent oocyte competence to be fertilized and to develop in vitro. All the obtained oocytes were classified according to the corresponding volume of aspirated follicular fluid. Aspirated volume of follicular fluid <2 ml corresponded to a follicular diameter <16 mm and const...

In this study, oocyte steroidogenesis are investigated in relation to oocyte development in the starry flounder, Platichthys stellatus, a marine multiple spawner. Vitellogenic (0.52 and 0.55 mm oocyte diameter) and mature oocytes (0.63, 0.66 and 0.71 mm oocyte diameter) were incubated in vitro in the presence of [(3)H]17α-hydevrepoxyprogesterone ([(3)H]17α-OHP) as a precursor. Steroid metabolit...

During oocyte growth, the morphology of the nucleolus changes into a compact and homogenous structure. The compact nucleoli in full-grown oocytes are not stained by aceto-orcein staining or immunofluorescence staining. In this study, we developed a hematoxylin staining method for pig oocytes in whole-mount preparations to visualize the nucleoli. Nucleoli of growing and full-grown oocytes were s...