|
KMID : 0900919990230040313
|
|
Korean journal of Animal Reproduction
1999 Volume.23 No. 4 p.313 ~ p.321
|
|
|
Comparison of Open Pulled Straw (OPS) vs Glass Micropipette (GMP) Vitrification in IVP Bovine Blastocysts
|
|
Kong I.-K.
Cho S.-G.
|
|
|
Abstract
|
|
|
|
The purpose of these study was to investigate the use of a glass micropipette (GMP) as a vessel for vitrification of bovine IVP blastocysts, to compare the post-thaw survival rates of bovine blastocysts frozen in GMP with those frozen in OPS that have been previously investigated, and to improve the hatching rate following vitrification with GMP method. The GMP vessel permits higher freezing and warming rate than the OPS due to the higher heat conductivity of the glass and lower mass of the solution that contains the embryos. Groups of three bovine IVP blastocysts were sequentially placed into vitrification solution before being loaded into either the OPS or GMP vessels and immersed into LN_2within 20 to 25 sec. Post-thaw blastocysts were serially washed in 0.25 and 0.15 M sucrose in HM and TCM-199 for each 5 min, respectively, and then cultured in TCM 199 supplemented with 10% FCS for 24 h. The rate of blastocyst re-expanding did not significantly different for OPS (75.9%) and GMP (80.0%) methods (P＞0.05). The hatching rates in OPS (34.1%) and GMP (37.5%) methods were significantly lower than that in control group (54.3%) (P＞0.05). In addition, the rate of blastocyst re-expanding was significantly lower if blastocysts were vitrified in the wide portion of the micropipette rather than the narrow portion of the micropipette (83.3 vs 56.7%) (P＞0.05), even though three blastocysts were loaded per vessel. The hatching rate in 0.05% pronase solution treatment for 30, 60 and 90 see (45.9, 54.7 and 57.5%) were significantly higher than that in control (35.0%), even though there was not significantly different between 30 see and control. These results indicate that both vitrification vessels can provide high survival rates of bovine IVP blastocysts. However, the GMP vessel has the advantage over the OPS, in that the former does not need a cap to protect the vessel from floating after immersion in LN_2. The location of the embryos (narrow or wide portion of immersion) were considered to be limiting factors to the viability of bovine IVP embryos. The exposing in 0.05% pronase solution for 60 or 90 see can increase hatching rates of post-thaw bovine IVP blastocysts.
|
|
|
KEYWORD
|
|
|
OPP, GMP, Bovine, Vitrification
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
|
|
|