OBJECTIVE The present study investigates pre- and post-implantation developmental competence of nuclear-transferred porcine embryos derived from male and female fetal fibroblasts. METHODS Male and female fetal fibroblasts were transferred to in vitro-matured enucleated oocytes and in vitro and in vivo developmental competence of reconstructed embryos was investigated. And, a total of 6,789 fe...

This study was designed to investigate the effect of vitrification and post-thaw survival and chromosomal aberrations caused by vitrification of vitrified 8-cell mouse embryos in comparison with a control group. To this purpose the survival rate and the frequency of chromosomal aberrations were assessed in frozen-thawed 8-cell mouse embryos after various storage durations in the presence of eth...

A scoring system specific for day 3 embryos has not been extensively explored. Most IVF laboratories continue to grade embryos solely on the basis of cell number and percentage fragmentation as was traditionally done for day 2 embryos. Additional morphological features, some unique to day 3 embryos, may be useful in selecting embryos most likely to blastulate and implant. The objective of this ...

introduction: this investigation was undertaken to examine the effect of 4centigrade degree temperature on development and implantation rate of mouse embryos. materials and methods: femal mice (4-6 week old) were induced to superovulate and were mated. two cell embryos were flushed from excited oviducts, 46 – 48 h after the infection of hcg, and were cultured to eight – cell stage in m16 medium...

We studied the developmental potential of single blastomeres from early cleavage mouse embryos. Eight- and sixteen-cell diploid mouse embryos were disaggregated and single blastomeres from eight-cell embryos or pairs of sister blastomeres from sixteen-cell embryos were aggregated with 4, 5 or 6 tetraploid blastomeres from 4-cell embryos. Each diploid donor embryo gave eight sister aggregates, w...

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...

BACKGROUND The purpose of this study was to evaluate the respective influences of blastomere survival and resumption of mitosis on the outcome of frozen-thawed embryos. METHODS A retrospective analysis was performed in our centre on 363 thawing cycles, involving 4-cell day 2 grade 1 embryos with <10% fragmentation. RESULTS A higher implantation rate per transferred embryo was observed when ...

ABSTRACT In mammals, sperm-borne regulators can be transferred to oocytes during fertilization and have different effects on the formation of pronuclei, first cleavage zygotes, development preimplantation embryos even metabolism individuals after birth. The regulatory role sperm microRNAs (miRNAs) in bovine has not been reported detail. By constructing screening miRNA expression libraries, we f...

Background: Arresting in a certain step of development like two-cell stage could be one of the reasons of infertility. The aim of this study is evaluating the effects of ethanol and strontium on growth and development of two-cell arrested mouse embryos. Materials and Methods: The females were coupled with male following superovulation. Positive vaginal plug mice were killed 48 hours after hCG i...