Effect of post-IVF developmental kinetics on in vitro survival of vitrified-warmed domestic cat blastocysts

Reprod Domest Anim. 2008 Jun;43(3):323-327. doi: 10.1111/j.1439-0531.2007.00902.x. Epub 2007 Dec 7.

Abstract

A limited number of reports is available on cryopreservation of in vitro fertilization (IVF)-derived cat blastocysts. In the present study, IVF-derived domestic cat embryos which reached the blastocyst stage either on day 6 or day 7 were cryopreserved by vitrification using Cryotop as a cryodevice. Fresh control and post-warm surviving blastocysts were examined by differential cell staining with Hoechst 33342 and propidium iodide to determine total cell number and inner cell mass (ICM) ratio, and the post-warm survival rate was determined by re-expansion of the blastocoel during 24 h of in vitro culture. In fresh control, the mean number of total cells of day 7 blastocysts (61.4 cells) tended to be smaller than that of day 6 blastocysts (81.9 cells, p = 0.096). The post-warm survival rates of day 6 and day 7 blastocysts were not statistically different (73.8%; 31 of 42 vs 66.7%; 18 of 27). There were no significant differences in the total cell number and ICM ratio between fresh control and vitrified blastocysts, although the ICM ratio of surviving day 7 blastocysts was significantly smaller than that of fresh controls (stained at day 8, 18.9% vs 28.9%, p < 0.05). These results indicate that IVF-derived domestic cat embryos that reached the blastocyst stage earlier can survive the Cryotop vitrification without a reduction in the parameters studied.

MeSH terms

  • Animals
  • Blastocyst / physiology*
  • Cats / embryology*
  • Cell Count / veterinary
  • Cell Survival
  • Cryopreservation / methods
  • Cryopreservation / veterinary*
  • Embryo Culture Techniques / methods
  • Embryo Culture Techniques / veterinary*
  • Embryo, Mammalian / physiology
  • Embryonic Development / physiology*
  • Female
  • Fertilization in Vitro / veterinary*
  • Kinetics