To determine the critical cell numbers needed to form blastocyst stage embroys, bisected mouse embryos of 8-cell stage and compacted morula (approximately 16 cells) containing different numbers of blastomeres were cultured in vitro. The percentage of bisected compacted morulae with 7-9 blastomeres that developed to eu-blastocysts was 98.8%, while only 64.2% of the bisected 8-cell embryos with 4...

Embryonic stem cells (ESCs) are originally derived from the ICM of blastocysts and are characterized by their ability to self-renew and their pluripotencies. Only a few reports have been published on ESC isolations and line establishment in animals, even fewer in horses. However, it is still important to isolate equine ESCs for animal biotechnology and therapeutic applications. In the present s...

We have developed a protocol using recombinant human follicle-stimulating hormone (rhFSH) to induce ovarian stimulation in the mouse to investigate its impact on preimplantation embryo development. Embryos were collected from adult female C57Bl/6 x CBA F1 mice treated with rhFSH (0, 2.5, 5.0, 10.0, or 20.0 IU) or 5 IU equine chorionic gonadotropin (eCG). Embryos were also recovered from nontrea...

Recent studies involving a limited number of patients have indicated a correlation between aneuploidy and various morphokinetic parameters during preimplantation development. The results among different groups, however, have been inconsistent in identifying the parameters that are able to predict chromosomal abnormalities. The aim of this study was to investigate whether aneuploidy of human bla...

background: preparation of oocytes is one of the critical factors that determine the developmental competence of embryos produced by in vitro fertilization (ivf). objective: in this study, the effect of cysteamine, type of media and glutathione (gsh) level on blastocysts development after in vitro maturation of mouse oocytes were investigated. materials and methods: premature female mice were p...

Embryo electrofusion and tetraploid blastocyst microinjection is a modification of the traditional embryonic stem cell (ES cell)-based method to generate targeted mutant mice. Viability of tetraploid embryos is reportedly lower than with diploid embryos, with considerable interstrain variation. Here we assessed fetus and pup viability after ES cell microinjection of tetraploid blastocysts deriv...

As a model for the detection of human genetic disease in preimplantation embryos, we describe a method in which trophectoderm biopsy samples from viable mouse blastocysts are simultaneously analyzed for the presence of a normal or mutant allele of the myelin basic protein gene by the polymerase chain reaction. The biopsied embryos are kept in culture during analysis of biopsied material and lat...

The prolificacy of two rabbit strains (Californian and New Zealand) has been studied in parallel with ovulation rate and embryonic development. The number of mean ovulations was 11.6 in Californians and only 9.6 in New Zealand. In spite of the higher rate in the former, the number of young born was about 8 in both strains. Californian and New Zealand blastocysts were transferred at 96 h post-co...

A cell-free culture system was designed for human embryo development to the blastocyst stage by testing a range of culture conditions in a series of protocols. The culture system that was evolved has a brief 1 h exposure to spermatozoa and then culture of the pronucleate zygote for 2 days in IVF-50 medium. Two or three embryos were cultured together in 20 microl microdrops of medium under oil. ...