The effect of stage maturation the germinal vesicle porcine oocytes at time in vitro on subsequent developmental competence was examined. A large variation exists morphology collection cumulus-oocyte complexes (COCs) and after culture absence dibutyryl cAMP (dbcAMP) for 20 h. However, synchronized to a specific presence 1 mM dbcAMP There no difference breakdown rate (total mean, 75.0 ± 5.4%) or 82.1 2.1 %) 28 44 h culture, respectively. differences meiotic progress were observed (p < 0.05)...

The effect of hormone supplements on cytoplasmic maturation in vitro was examined by incubating oocyte–cumulus complexes a medium with PMSG (10 iu ml−1), hCG ml−1) and oestradiol (1 μg for various periods then transferring them to without added hormones the remainder period. Exposure 2 h improved only germinal vesicle breakdown rates compared not exposed hormones. removal at 20 after start culture enhanced ability oocytes form male pronuclei 10 12 insemination. Further, effects transfer...

The effects of sodium chloride (NaCI) in Whitten's medium on intracellular glutathione concentration and cytoplasmic maturation, as determined by monospermic penetration male pronuclear formation porcine oocytes, were examined. Porcine cumulus-oocyte complexes cultured for 20 h BSA-free containing different NaCl concentrations (44.50, 68.49, 92.40, 116.40, or 140.35 mM) supplemented with 10% follicular fluid hormonal supplements; the then without supplements an additional 20-h period. mean...

Porcine cumulus-oocyte complexes were cultured in BSA-free Whitten's medium or modified Medium 199, each supplemented with porcine follicular fluid (PFF) and hormonal supplements (OMWM OMM199, respectively) for 20 h; they then without an additional (experiments 1 3) 24 h (experiment 2). At the end of culture 1), intracellular glutathione concentration was higher (p < 0.05) oocytes matured OMWM vs. OMM199. After activation by Ca2+ ionophore 2), incidence group lower 0.01) than OMM199 group....

The effects of porcine follicular fluid (PFF) on sperm penetration pig oocytes and prevention polyspermy were examined characteristics spermatozoa exposed to PFF determined. addition at the level 1 10% prefertilization fertilization media decreased rates mean number in penetrated eggs regardless origin PFF. In presence BSA, supplementation 0.1% 1% did not decrease but increase monospermic 54 68%, respectively. When was added media, binding zona percentage acrosome-intact with increased...

Microtubule and microfilament organization in porcine oocytes during maturation vivo vitro was imaged by immunocytochemistry laser scanning confocal microscopy. At the germinal vesicle stage, microtubules were not detected oocyte. After breakdown, a small microtubule aster observed near condensed chromatin. During prometaphase asters found association with each chromatin mass. The then elongated encompassed at metaphase-I stage. anaphase-I telophase-I meiotic spindle. Microtubules only...

Microtubule configurations in porcine oocytes after sperm penetration or artificial activation by electrical stimulation were imaged immunocytochemistry and laser scanning confocal microscopy. Soon penetration, an aster was seen adjacent to the incorporated head. Polyspermic penetrations led presence of multiple asters association with each sperm. The enlarged and, at time pronuclear apposition, filled cytoplasm. After male female gamete union, microtubule matrix reduced. At mitotic...

Rat one-cell embryos recovered from naturally mated females were cultured in modified hamster embryo culture medium 1 without amino acids. In the presence of 0.4 mmol phosphate l−1 (NaH2PO4), no developed beyond two-cell stage, regardless 5.0 glucose l−1. This inhibition was dose dependent at very low concentrations supplemented with 7.5 and osmolarity adjusted to 244 mosmol; development blastocyst stage not inhibited 0.001–0.01 μmol l−1, but morula four-cell stages markedly 0.1 1.0...

A suitable chemically defined culture medium for 1-cell rat embryos (mR1ECM) was modified to obtain sperm penetration, and the developmental competence of oocytes fertilized in compared that a traditional medium, Krebs-Ringer bicarbonate (mKRB). Sperm penetration not observed when polyvinyl alcohol replaced with BSA mR1ECM (mR1ECM-BSA); incidence improved only osmolarity mR1ECM-BSA increased mKRB (310 mOsm) by addition NaCl. The proportion penetrated NaCl (71.6 ± 6.9%), which different (76.7...

The effects of oviductal fluid on sperm penetration and cortical granule exocytosis in pigs were examined. Cortical oocytes matured vivo vitro was observed by staining with fluorescent-labelled lectin laser-scanning confocal microscopy. Exocytosis classified into three categories after fertilization: complete even distribution exudate the entire perivitelline space (type I); partial II) incomplete III). incidence type I higher than those vitro. addition at a concentration 1% or 10% to...

Cytoplasmic maturation as determined by male pronuclear formation following fertilization in vitro was examined pig oocytes cultured under different hormonal conditions during either the first or second 20 h period of maturation. Exposure to several combinations pregnant mares' serum gonadotrophin (PMSG) (10 iu ml−1), hCG ml−1) and oestradiol (1 μg for a culture medium supplemented with these hormones did not result differences among treatment groups rates, penetration rates polyspermy...

The effects of organic osmolytes on cytoplasmic maturation porcine oocytes were examined in medium (modified Whitten′s medium) containing various NaCI concentrations. presence osmolytes, such as taurine and sorbitol, at 6 12 mM 68.49 or 92.40 increased oocyte glutathione content. Microfilament organization was disrupted the higher level (92.40 mM). However, supplementation with sorbitol to reduced severity abnormality. Early embryonic development vitro blastocyst stage 8.3 ± 0.9% for matured...

The presence of different intracellular Ca 2+ release mechanisms in porcine oocytes and their involvement mediating transients developmental stages were investigated. Metaphase II arrested showed an increase concentration after injection inositol 1,4,5-trisphosphate (InsP3), the InsP3 receptor agonist. Similar spikes could be detected ryanodine cyclic ADP ribose, agonists. InsP3-induced was inhibited by heparin, antagonist, whereas procaine, blocked generated ribose. In germinal...

Effects of caffeine and adenosine on the function in vitro penetration frozen–thawed boar spermatozoa were examined. First, effect sperm was determined by chlortetracycline fluorescence assessment. Both stimulated capacitation spermatozoa. However, adenosine, but not caffeine, inhibited spontaneous acrosome loss. Second, into matured oocytes compared among cultured absence or presence adenosine. increased rate (99.1 ± 0.9% 72.4 2.0% vs. 54.8 5.1% controls) only decreased drastically...

To induce meiotic resumption of porcine oocytes, it is thought to be necessary expose the cumulus-oocyte complexes (COCs) gonadotropins during in-vitro maturation (IVM). However, detailed mechanism by still unknown, and successful piglet production has not been reported using oocytes matured in gonadotropin-free media fertilized vitro. The present study was undertaken examine combinational effects epidermal growth factor (EGF)-family members dibutyryl cyclic AMP (cAMP) a chemically defined...