Abstract: 30

COMPARISON OF OPEN PULLED STRAW VERSUS OPEN PULLED CAPILLARY PIPETTE VITRIFICATION IN MOUSE EMBRYOS.

Il-Kuen Kong¹ , S.G. Cho¹ , S.I. Lee¹ , S.K. Cho²
Dept of Anim Sci, Sunchon Natl Univ, Sunchon ¹
Gyeongsang Natl Univ, Chinju, S. Korea ²

Several studies using different vitrification methods have been reported high survival rates in various species embryos. The success of vitrification could be affected the amount of the intracellular lipid droplets and the different microtubular structure leading to chilling injury as well as the volume/surface ratio influencing the penetration of cryoprotectants. We compared open pulled straw (OPS) vs open pulled capillary pipette (OPP) vitrification method with 40%(v/v) ethylene glycol, 18%(w/v) Ficoll, 0.3 M sucrose solution in holding medium (D-PBS plus 5% CS: HM)(EFS; Tachikawa et al., 1993) or 16.5% ethylene glycol, 16.5% DMSO, 0.5 M sucrose in HM (EDS; Vajta et al., 1998). The OPP (od/id: 1.0/0.8 mm capillary pipette; Drummond, USA) were heat-softened over alcohol frame and pulled manually until the i.d. decreased from 0.8 mm to approximately 0.5 mm. The pipette were cooled in air, then cut with diamond tip. The blastocyst were collected at 90 h after hCG injection. All treatments were replicated 10 times and cryopreserved around 6 embryos in each time. The post-thawed embryos were cultured in mHTF medium for 48 h. The re-expended and hatched rates in OPS with EFS or EDS (94.6 or 98.4% and 89.3 or 93.5%) were not significant difference in OPP with EFS or EDS (93.3 or 96.7% and 90.0 or 95.0%)(P<0.05). These results indicate that OPP as well as OPS method could be use for vitrification of mouse blastocysts, even when cryopreserved with EFS or EDS cryoprotectant. The volume and cooling rates of cryoprotectant containing embryos is primary important in vitrification method.

    This abstract is being presented on Sunday, August 1 at 8:00 AM to 10:15 AM at CUB 2nd Floor Ballroom.