Open pulled straw vitrification and slow freezing of sheep IVF embryos using different cryoprotectants.

The aim of the present study was to evaluate the post-thaw survival and hatching rates of sheep blastocysts using different cryoprotectants. In Experiment 1, Day 6 sheep embryos were cryopreserved by a slow freezing protocol using 10% ethylene glycol (EG), 10% dimethyl sulfoxide (DMSO) or a mixture of 5% EG and 5% DMSO. Hatching rates were higher in the 10% EG group than in the 10% DMSO or EG + DMSO groups (30% vs 18% and 20%, respectively). In Experiment 2, embryos were cryopreserved by open pulled straw (OPS) vitrification using either 33% EG, 33% DMSO or a mixture of 16.5% EG + 16.5% DMSO. Re-expansion and hatching rates in the EG + DMSO group (79.16% and 52.74%, respectively) were higher than those in the EG group (64.28% and 30.02%, respectively), whereas the outcomes for the DMSO group were the lowest (45.18% and 8.6%, respectively). In Experiment 3, embryos were cryopreserved by OPS vitrification using either 40% EG, 40% DMSO or a mixture of 20% EG + 20% DMSO. Re-expansion and hatching rates were highest in the EG group than in the EG + DMSO and DMSO groups (92.16% vs 76.30% and 55.84% re-expansion, respectively; and 65.78% vs 45.55% and 14.46% hatching, respectively). In conclusion, OPS vitrification was found to be more efficient for cryopreservation of in vitro-developed sheep embryos than traditional freezing.

[1]  M. Betancourt,et al.  Viability, maturation and embryo development in vitro of immature porcine and ovine oocytes vitrified in different devices. , 2012, Cryobiology.

[2]  A. Gibbons,et al.  A simple vitrification technique for sheep and goat embryo cryopreservation , 2011 .

[3]  M. Gauly,et al.  Open pulled straw vitrification of goat embryos at various stages of development. , 2010, Theriogenology.

[4]  R. E. Green,et al.  Viability of OPS vitrified sheep embryos after direct transfer. , 2009, Reproduction in domestic animals = Zuchthygiene.

[5]  C. Aragona,et al.  Ongoing pregnancies after vitrification of human oocytes using a combined solution of ethylene glycol and dimethyl sulfoxide. , 2006, Fertility and Sterility.

[6]  G. Iorio,et al.  Cryopreservation of in vitro-produced ovine embryos , 2006 .

[7]  G. Vajta,et al.  Are programmable freezers still needed in the embryo laboratory? Review on vitrification. , 2006, Reproductive biomedicine online.

[8]  M. J. Cocero,et al.  Culture of early stage ovine embryos to blastocyst enhances survival rate after cryopreservation. , 2005, Theriogenology.

[9]  K. Niwa,et al.  Effects of partial removal of cytoplasmic lipid on survival of vitrified germinal vesicle stage pig oocytes. , 2005, The Journal of reproduction and development.

[10]  G. Vajta,et al.  Highly efficient vitrification method for cryopreservation of human oocytes. , 2005, Reproductive biomedicine online.

[11]  P. Cappai,et al.  Comparison of different vitrification protocols on viability after transfer of ovine blastocysts in vitro produced and in vivo derived. , 2004, Theriogenology.

[12]  P. Lonergan,et al.  Temporal sensitivity of bovine embryos to culture environment after fertilization and the implications for blastocyst quality. , 2003, Reproduction.

[13]  C. Furnus,et al.  Vitrification of in vitro produced bovine embryos: in vitro and in vivo evaluations. , 2002, Animal reproduction science.

[14]  Dimitrios Rizos,et al.  Developmental, qualitative, and ultrastructural differences between ovine and bovine embryos produced in vivo or in vitro , 2002, Molecular reproduction and development.

[15]  R. C. Evans,et al.  Polymorphic distribution of the ovine prion protein (PrP) gene in scrapie-infected sheep flocks in which embryo transfer was used to circumvent the transmissions of scrapie. , 2002, Theriogenology.

[16]  Martin P Robinson,et al.  Vitrification media: toxicity, permeability, and dielectric properties. , 2002, Cryobiology.

[17]  P. Mermillod,et al.  Successful direct transfer of vitrified sheep embryos. , 2001, Theriogenology.

[18]  A. Massip.  Cryopreservation of embryos of farm animals. , 2001, Reproduction in domestic animals = Zuchthygiene.

[19]  P. Palta,et al.  Post-vitrification survival and in vitro maturation rate of buffalo (Bubalus bubalis) oocytes: effect of ethylene glycol concentration and exposure time. , 2000, Animal reproduction science.

[20]  X. Yang,et al.  High Developmental Rates of Vitrified Bovine Oocytes Following Parthenogenetic Activation, In Vitro Fertilization, and Somatic Cell Nuclear Transfer1 , 2000, Biology of reproduction.

[21]  S. Emiliani,et al.  Comparison of ethylene glycol, 1,2-propanediol and glycerol for cryopreservation of slow-cooled mouse zygotes, 4-cell embryos and blastocysts. , 2000, Human reproduction.

[22]  H. R. Tervit,et al.  Effects of vitrification medium composition on the survival of bovine in vitro produced embryos, following in straw-dilution, in vitro and in vivo following transfer. , 2000, Animal reproduction science.

[23]  D. Gardner,et al.  Vitrification of mouse and human blastocysts using a novel cryoloop container-less technique. , 1999, Fertility and sterility.

[24]  G. Vajta,et al.  Open pulled straw (OPS) vitrification: A new way to reduce cryoinjuries of bovine ova and embryos , 1998, Molecular reproduction and development.

[25]  G. Vajta,et al.  Vitrification of Porcine Embryos using the Open Pulled Straw (OPS) Method , 1997, Acta Veterinaria Scandinavica.

[26]  N. Fujihara,et al.  Usefulness of polyethylene glycol for cryopreservation by vitrification of in vitro-derived bovine blastocysts. , 1997, Animal reproduction science.

[27]  N. Songsasen,et al.  Development into blastocysts of bovine oocytes cryopreserved by ultra-rapid cooling. , 1996, Biology of reproduction.

[28]  G. Vajta,et al.  Overall efficiency of in vitro embryo production and vitrification in cattle. , 1996, Theriogenology.

[29]  N. Songsasen,et al.  In vitro and in vivo survival of cryopreserved sheep embryos. , 1995, Cryobiology.

[30]  T. Otoi,et al.  Effect of trypsin treatment of in vitro fertilized bovine embryos on their subsequent survival and development. , 1993, The Journal of veterinary medical science.

[31]  H. Sakul,et al.  Cryopreservation of embryos as a means of germ plasm conservation in sheep. , 1993, Theriogenology.

[32]  G M Fahy,et al.  Ice-free cryopreservation of mouse embryos at -196 degrees C by vitrification. , 1985, Nature.