Vitrification of ICSI- and IVF-derived bovine blastocysts by minimum volume cooling procedure: effect of developmental stage and age

Theriogenology. 2010 Oct 1;74(6):1028-35. doi: 10.1016/j.theriogenology.2010.04.033. Epub 2010 Jun 30.

Abstract

The objective was to investigate the effects of developmental stage (fully-expanded or expanding blastocysts) and/or age (harvested on Days 7 or 8) on post-vitrification in vitro survival of bovine blastocysts derived from intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF). Post-warming survival (re-expansion of blastocoele within 24 h) of ICSI-derived fully-expanded blastocysts (80%) was similar to that of their IVF-derived counterparts (88%). However, the ability of ICSI-derived expanding blastocysts to survive vitrification procedures (61%) was lower than that of IVF-derived blastocysts (85%; P < 0.05), although the ICSI- and IVF-derived fresh blastocysts were of similar quality. The age of the blastocysts before vitrification did not affect cryotolerance for either ICSI-derived (73 and 59% for Days 7 and 8 embryos, respectively) or IVF-derived blastocysts (86% for both Days 7 and 8 embryos). At 24 h of post-warming culture, ICSI-derived blastocysts surviving vitrification contained a higher proportion of dead cells than their IVF-derived counterparts (5-13% vs. 2-4%; P < 0.05), but these proportions were not different from those of fresh control embryos. There was an adverse effect of vitrification on the ability of blastocysts to hatch within 72 h of culture only in IVF-derived Day 8 blastocysts (41 and 70% in vitrified and fresh control groups, respectively). In conclusion, the proportion of blastocysts that survived vitrification procedures was similar for ICSI- and IVF-derived bovine blastocysts if the former were cultured to the fully-expanded stage prior to vitrification, with no significant difference between embryos harvested on Day 7 versus Day 8.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blastocyst*
  • Cattle* / physiology
  • Cell Size
  • Cell Survival
  • Cells, Cultured
  • Cleavage Stage, Ovum / physiology*
  • Cryopreservation / methods*
  • Cryopreservation / veterinary
  • Embryo Culture Techniques / veterinary
  • Embryonic Development / physiology*
  • Female
  • Fertilization in Vitro / methods
  • Fertilization in Vitro / veterinary
  • Gestational Age
  • Male
  • Quality Control
  • Sperm Injections, Intracytoplasmic / methods
  • Sperm Injections, Intracytoplasmic / veterinary
  • Temperature