Controlled Freezing and Open-Pulled Straw (OPS) Vitrification of In vitro Produced Bovine Blastocysts Following Analysis of ATP Content and Reactive Oxygen Species (ROS) Level

To our knowledge, no single study has systemically compared cryopreservation efficiencies of bovine blastocysts derived from in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI) and somatic cell nuclear transfer (SCNT) by controlled freezing and vitrification. This experiment, therefore, was designed to compare the cryopreservation of these blastocysts with controlled freezing and OPS vitrification. Adenosine-5′-triphosphate (ATP) content and reactive oxygen species (ROS) level in blastocysts were also analyzed. Firstly, for each type of blastocyst (IVF, ICSI or SCNT), significant differences were observed between the survival rates of the controlled freezing ((81.56±2.33), (68.18±4.72) or (47.89±5.83)%) and OPS vitrification groups ((92.24±4.54), (82.40±3.76) or (78.71±5.91)%; P