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The efficiencies in producing cloned ruminant embryos and subsequent production of offspring are still low. The study was conducted to produce cloned goat and cattle embryos using inter- and intraspecies SCNT techniques. This study involved 3 different types of donor karyoplast using goat and cattle oocyte as a recipient cytoplast to produce cloned goat and cattle embryos. The results showed that fetal fibroblast cell (FFC) in interspecies SCNT gave significantly higher 2-cell (64.40 vs. 38.43%), 4-cell (54.24 vs. 24.60%), 8-cell (36.82 vs. 14.54%) and morula (22.10 vs. 7.90%) cloned goat embryos than ear fibroblast cell (EFC). As for intraspecies SCNT using cumulus cell (CC) as a donor karyoplast to produce cloned cattle and goat embryos, the values for cleavage rates were not significantly different which were; 53.57 vs. 57.17%, 33.17 vs. 46.40%, 22.15 vs. 27.30% and 11.90 vs. 15.59%, respectively for all embryo stages. Our results showed that cloned goat and cattle embryos could be produced using different types of donor karyoplast in intra- and interspecies SCNT. However, for goat-cattle interspecies SCNT, FFC was more efficient to produce cloned goat embryos compared to EFC.

Apoptosis in oocyte could be a good marker for oocyte quality and development competency. The study aims to investigate the relation between early apoptosis occurrence in different morphological groups of oocytes, i.e. Group A, B and C, and their developmental potential in terms of meiotic resumption to metaphase II. Annexin-V staining was used to detect early apoptosis in oocytes and Giemsa staining for meiotic resumption. Immature oocytes in Group B and C showed significantly high incidence of early apoptosis compared to Group A oocytes (A: 10.20%, B: 19.00% and C: 20.60%). After maturation, no differences were observed in the incidence of early apoptosis among oocytes from different groups (A: 28.40%, B: 18.20% and C: 23.00%). However, the mean percentage of early apoptosis increased among Group A oocytes after maturation. The progression to metaphase II were similar among the different groups of oocytes (A: 34.09%, B: 31.54% and C: 33.45%). In conclusion, early apoptosis occurrence in bovine oocytes is related to developmental competence.

Combination of different chemicals has been an effective method to activate oocytes. The objectives of this study were to evaluate the optimal: (1) concentration (Experiment 1) and duration (Experiment 2) of strontium chloride (SrCl2) in the presence of cytochalasin B (CB), (2) secondary activation agent [6-dimethylaminopurine (6-DMAP), cycloheximide (CHX) and CB] in combination with calcium ionophore (CaI) (Experiment 3) and (3) ethanol (EtOH) concentration in combination with 6-DMAP (Experiment 4). There were no significant (P>0.05) differences in cleavage (86.82–89.06%) and blastocyst (33.42–46.83%) rates when oocytes were treated with various concentrations of SrCl2 (2–10 mM). Three-hour duration generally showed the highest cleavage (93.83%) and blastocyst rates (60.42%) compared to other durations. Comparing with various combinations, CaI +6-DMAP showed the highest cleavage at all stages of development and significantly (P

This study evaluated the effects of oocyte source on in vitro maturation (IVM) and embryo developmental competence in goats by the intracytoplasmic sperm injection (ICSI) technique. Oocytes were obtained either by laparoscopic ovum pick-up (LOPU) or by slicing of abattoir ovaries. The donor does used for LOPU were superstimulated and their estrus was synchronized. Recovered oocytes from both sources were cultured in microdrops of IVM medium in the presence of CO2 (5%) at 38.5 °C in a CO2 incubator for 27 h. The ICSI was performed with immobilized sperm on the lid of a culture dish (35 mm) under an Olympus inverted microscope fitted with Narishige micromanipulators. Injected oocytes were cultured for

This study examines in-vitro maturation (IVM) in a non-human primate model, Macaca fascicularis . The animals had hormonal injections and laparoscopic oocyte retrieval (OR)) at 12- and 24- h after human chorionic gonadotrophin (HCG). The immature oocytes were placed in tightly capped tubes containing pre-equilibrated IVM medium and transported for 5 h in a dry portable 37°C incubator without CO 2 supplement. Meiotic spindle was observed at 36–38- h post-HCG by polarized microscopy in 72 and 84.5% of mature oocytes collected at 12- and 24- h post-HCG oocyte retrieval intervals respectively. However, abnormal spindle formations were detected in some IVM oocytes by confocal microscopy. The IVM oocytes were also randomly selected for (i) intracytoplasmic injection with frozen–thawed epididymal M. fascicularis spermatozoa and (ii) nuclear transfer (NT) with fresh M. fascicularis cumulus cells. Embryonic development of sperm-injected embryos was not affected by the 12- and 24- h post-HCG oocyte retrieval intervals (22.5 versus 27.9% respectively). However, embryonic development of NT embryos was significantly affected by the 12- h post-HCG oocyte retrieval interval (4.5 versus 31.7% respectively; P 0.01). In conclusion, IVM of monkey oocytes in a dry portable incubator for 5 h did not affect the maturation rate. However, the ability of primate oocytes to develop after somatic cell nuclear transfer was affected by oocyte retrieval time post-HCG.