Abstract
To survey the relationship between metabolic activity and developmental ability of bovine embryos derived from in vitro fertilization, we modified an enzymatic cycling method inthe present study. We measured 6-phosphogluconate dehydrogenase activity (6PGD) in singlebovine embryos derived from in vitro fertilization in preimplantation stages and checked theirdevelopmental ability. When measured by adding 6-phosphogluconate as a substrate, 6PGD activi-ties were 62.8±9.2, 77.4±3.3, 103.4±6.8, 96.2±0.5 and 120.6±3.4 (×10-9 mol/embryo/h) in the 2-cell, 4-cell, 8-cell, morula and blastocyst stage embryos, respectively, indicating significant differ-ences between groups at the 2-or 4-cell stages and blastocyst stage (P<0.05). In all cell stageembryos, the level of 6PGD activity increased by adding the substrate. When subsequent develop-ment was examined after measurement of 2-cell, 4-cell, 8-cell and morula stage embryos, thedevelopmental rate to blastocyst stage ranged from 18.8 to 61.0% and did not vary among the different stages.
