We have investigated the development of reconstituted embryos in which enucleated 1- or 2-cell embryos received various advanced nuclei. Enucleated 1-cells developed to the blastocyst stage only when an early 2-cell donor nucleus was transferred but very rarely if the donor nucleus was derived from a late 2-cell, early 4-cell or mid 8-cell embryo. Although an 8-cell nucleus could only support d...

Somatic cell nuclear transfer (SCNT) is considered to be a critical tool for propagating valuable animals. To determine the productivity calves resulting from embryos derived with different culture media, enucleated oocytes matured in vitro were reconstructed with fetal fibroblasts, fused, and activated. The cloned embryos were cultured in modified synthetic oviduct fluid (mSOF) or a chemically...

Receptivity is a limited time in which uterine endometrium can establish a successful dialogue with blastocyst. This study was to investigate the effect of asynchronous embryo transfer on uterine receptivity in mice. Embryos under different stages were transferred into two oviduct sides of a recipient mouse on day 1 of pseudopregnancy. Our results showed the asynchronously transferred embryos c...

The source and nature of zona lytic factors during zona escape of hamster blastocyts were investigated. When cultured in hamster embryo culture medium (HECM)-2h, all 8-cell embryos (n = 135) developed to zona escaped-blastocysts with complete zona lysis. In addition, 2-cell embryos, when co-cultured with zona escaping-blastocysts (at a ratio of 1:10), exhibited zona lysis. Various other embryos...

The present study examined the influence of post-cleavage time of nuclear donors on the development of reconstituted embryos in bovine nuclear transfer. Blastomeres of 16-cell stage embryos derived from in vitro-maturation, fertilization and culture were used as nuclear donor source. They were treated with 10 microM nocodazole for 12 hr. Blastomeres that cleaved within 3 hr after the removal of...

(SCNT) embryos of buffaloes. 2. To study gene expression profile of important developmental genes at different stages of SCNT cloned embryo. 3. To study epigenetic reprogramming during early developments of SCNT embryos Materials and Methods: Expression analysis of developmental genes was done in different (ovarian granulose and cumulus and skin fibroblasts) donor cells; in vitro maturing oocyt...

The aim was to report a healthy live birth using re-vitrified-warmed cleavage-stage embryos derived from supernumerary warmed embryos after frozen embryo transfer (ET) in a patient with recurrent implantation failure (RIF). The case was a 39-year-old female with a history of polycystic ovarian syndrome and adenomyosis, along with RIF. After ovarian hyperstimulation, 33 cumulus-oocyte complexes ...

Background: This retrospective study compared pregnancy outcomes from single embryo transfer (SET) with multiple embryo transfer (MET) in too young (≤25 years) and young (>25 years) infertile patients. Materials and Methods: Data from infertile patients who referred for ART treatment to Yazd infertility center during 1992 to 2012 were studied retrospectively. Records of patients with SET or MET...

The developmental capacity of (a) single blastomeres of 4-cell embryos, (Jb) pairs of blastomeres of 8-cell embryos and (c) single blastomeres of 8-cell embryos was studied. The blastomeres were inserted into evacuated foreign zonae pellucidae, embedded in agar, transferred to ligated oviducts of dioestrous ewes, and recovered when their total age was 5-Jto 6̂ days. At lecovery the majority of e...