Study on Isolation of Inner Cell Mass from Bovine Embryo Derived from <I>In Vitro</I> Fertilization by Exposure to Calcium Ionophore A23187

Abstract

The objective of this study was to investigate the effect of calcium ionophore A23187 (IA) on the isolation of inner cell mass (ICM) and trophoblastic tissue of bovine blastocyst derived from in vitro fertilization.Oocytes were aspirated from follicles of 2-5 mm in diameter of the ovaries and then were matured for 21h and fertilized in vitro. In vitro fertilized ova were co-cultured with cumulus cells for 7 or 10 days.In first experiment, Day 7 blastocysts were treated with IA. Treatments were 1) 10-30 min, 20μM; 2)10-30min, 100μM; 3) 40-60 min, 20μM; 4) 40-60 min, 100μM.In next experiment, Day 10 blastocysts were treated with IA. Treatments were 1) 10-30 min, 20 μM; 2) 10-30 min, 100μM; 3) 10-30 min, 200μM; 4) 40-60 min, 10μM; 5) 40-60 min, 100μ M; 6) 40-60 min, 200μM.When Day 7 blastocysts were treated for 10-30 min, 20μM, the isolation rate (81.8%) was significantly higher (P<0.05) than the other treatments. On the other hand, using Day 10 blastocysts significantly higher isolation rate (80.0-91.2%) were obtained with 40-60min, 100μM or 200μM.In conclusion, our experiment demonstrated that bovine ICM can be isolated with IA treatment and the treatment conditions were different with the age of embryos. embryos.