A commercially viable cattle embryo transfer (ET) industry was established during the early 1970s. Initially, techniques for recovering and transferring cattle embryos were exclusively surgical. However, by the late 1970s, most embryos were recovered and transferred nonsurgically. Successful cryopreservation of embryos was widespread by the early 1980s, followed by the introduction of embryo sp...

OBJECTIVE To evaluate and compare the laboratory and clinical outcomes of vitrification with slow-freezing method for cryopreservation of embryos and blastocysts in an in-vitro fertilisation programme. DESIGN Retrospective analysis of all the 104 cycles of frozen embryo and blastocyst replacements from 2003 to 2008 and all the 149 cycles with embryos or blastocysts for vitrification from 2006...

This study examined whether the viability, determined in vitro, of DNA-injected bovine embryos produced in vitro was affected by freezing, and if the frozen embryos developed to term following transfer to recipients. In vitro fertilized zygotes were injected with the pBL1 gene and then co-cultured with mouse embryonic fibroblasts (MEF) in CR1aa medium. Embryos were prepared for cryopreservation...

The aim of the study was to analyse the toxicity, the osmolar and cryoprotective activity of ethylene glycol (ETG) in terms of survival rate (SR), cleavage rate (CR) and expanded blastocysts percentage (EBP) of mouse embryos. Early mouse embryos and blastocysts were slowly cooled with ETG, 1,2-propanediol (PROH) or glycerol, and thawed. The Van t'Hoff curve for 1.5 mol/l ETG showed recovery of ...

The matter of ‘abandoned embryos’ arises when surplus IVF embryos are frozen and stored for later use. If the fertility clinic or storage facility in question does not have clear direction about what to do with these embryos, and/or payment for storage ceases, and/or the embryo providers cannot be reached, the embryos raise an ethical and practical challenge. On the one hand, there is a commitm...

On a worldwide basis, more than 750,000 embryos are produced annually from superovulated donors and more than 450,000 embryos are produced using in vitro techniques. Superovulation and embryo collection are done as frequently as every 30 days. Cryopreservation and direct transfer of frozen-thawed embryos results in pregnancy rates near that of fresh embryos. Since the zona pellucida-intact in v...

Canine embryos (8-cell to blastocyst stages) frozen-thawed using the slow-freezing method with glycerol (four recipients) or dimethyl sulfoxide (three recipients) as a cryoprotectant and vitrified-warmed using the Cryotop method (five recipients) were surgically transferred into the unilateral uterine horn of recipient bitches. As a result, the morphology of embryos frozen-thawed using the slow...