抄録
Oocytes were aspirated and collected into modified PBS from follices in bovine ovaries obtained from slaughter house. These oocytes were washed twice with PBS and kept in mPBS for 1, 2, 3, 4 and 5 hours at 37°C respectively until they began to culture for maturation. After keeping at each hour, the oocytes were transferred into culture medium (25mM Hepes Buffered TCM-199 supplemented with 5% FCS), and then culture in an atmospher containing 5% CO2 in air at 38.5°C during 20-22hours. For in vitro fertilization, each 10-20 matured oocytes were suspended in 100g1 of BO solution which was adjusted sperm concentration to 4×106/ml and added with caffeine (5mM/ml) and heparin (10μg/ml). After a spermoocyte mixing was co-incubated for 6 hours, and then these fertilized ova were transferred into the TCM-199 (earl's salt) supplemented with 1% FCS and continued to culture for development. The maturation rates to Metaphase-II of 1 (78%) or 2 h ours (7096) were significantly higher (P<0.05) than those of 3 (49%) or 4 hours (31%), respectively, and the clervage rates of 4 (2896) or 5 hours (3296) were significantly lower (P<0.05) than that of 1 (78%), 2 (7296) or 3 hours (62%), respectively. The rates of blastocyst developed in lhours (13.396) was significantly higher (P<0.05) than that of 2 (7.1%) or 3 hours (5.6%), respectively. There were no development of blastocyst in the case of 4 and 5 hours. these results indicate that oocytes kept on shorter times are increasing in their development to blastocyst stages than those of longer times for transfer into maturation media after collection of oocytes.
