Background: This study was designed to respond to the controversy regarding the necessity of oocyte activation after the ICSI procedure for normal embryo development in sheep. Materials and Methods: The effect of chemical stimulation with either 5mM ionomycin (I) for 5 minutes or ionomycin + 2 mM 6-dimethylaminopurine (6-DMAP) for 3 hours on the efficiency of ICSI, was compared in six experimen...

Background: Artificial oocyte activation (AOA) has important implications in assisted reproductive technique (ART) with particular importance in somatic cell nuclear transfer (SCNT). Parthenogenesis activation using zona- free oocytes offers an alternative model that could be applied to develop protocols for the activation of reconstructed embryos for cloning. Materials and Methods: To establis...

Parthenogenetic activation of mammalian oocytes with artificial stimuli is commonly applied in various reproductive biotechniques, e.g. cloning using nuclear transfer. For this reason, many studies focus on oocyte activation in vitro. Recently we have described the activation of pig oocytes using nitric oxide. This activating stimulus is very specific in many aspects. However, it does not provi...

The objective of this study was to determine the effects of 3 chemical agents used sequentially and electrical stimuli on parthenogenetic activation of in vitro matured bovine oocytes and comparison with a standard IVF protocol for embryo developmental rates. For this purpose, oocytes were matured in tissue culture medium-199 (TCM-199) at 39 °C and 5% of CO2 in humidified air. For IVF, matured ...

in vitro maturation (ivm) was carried out in the presence of different concentrations (10, 50, 100 or 200 µm) of α-linolenic acid (ala). embryonic cleavage, blastocyst formation following parthenogenetic activation (pa) and in vitro fertilization (ivf), and numbers of total and apoptotic cells in blastocyst were then determine for the 50 μm concentration and compared with the control group. out...

the aim of this study was to compare the effect of time of parthenogenetic activation (22 hr versus 27 hr after in vitro maturation-ivm) on in vitro development of ovine oocytes using either single (ionomycin 5 ?m for 5 min or ethanol 7% for 7 min) or combined (ionomycin and ethanol with 6-dmap 2 mm for 3 hr) activation treatments. the abattoir-derived in vitro matured activated oocytes were cu...

The aim of the study was to compare the parthenogenetic activation and in vitro fertilization (IVF) of in vitro matured caprine oocytes. A total of 881 cumulus-oocyte complexes (COC’s) were collected from 243 ovaries. Oocytes were matured in TCM-199 medium containing eCG (20 IU/ml), hCG (20 IUμg/ml), oestradiol-17β (1 μg/ml), BSA embryo tested (3 mg/ml) supplemented with 10% fetal bovine serum ...

the aim of the study was to compare the parthenogenetic activation and in vitro fertilization (ivf) of in vitro matured caprine oocytes. a total of 881 cumulus-oocyte complexes (coc’s) were collected from 243 ovaries. oocytes were matured in tcm-199 medium containing ecg (20 iu/ml), hcg (20 iuμg/ml), oestradiol-17β (1 μg/ml), bsa embryo tested (3 mg/ml) supplemented with 10% fetal bovine serum ...

Nitric oxide (NO) is identified as a signaling molecule involved in many cellular or physiological functions including meiotic maturation and parthenogenetic activation of mammalian oocytes. We observed that nitric oxide donor SNAP was potent to induce parthenogenetic activation in Xenopus eggs. NO-scavenger CPTIO impaired the effects of SNAP, providing evidence for the effects of the latter to...

These experiments were carried out to optimize the parameters of electrical activation, methods of parthenogenetic activation and embryo culture in vitro and meanwhile to isolate embryonic stem cells-like (ESCs) derived from porcine parthenogenetic blastocysts (pPBs). These results showed that, as the electric field strength increased from 1.0 to 2.7 kV/cm, the cleavage rate of parthenogenetic ...