Effects of Cycloheximide on Parthenogenetic Development of Pig Oocytes Activated by Ultrasound Treatment

The present study was carried out to examine the parthenogenetic development of pig oocytes treated with different concentrations of cycloheximide for different durations following activation by ultrasound stimulation. When oocytes were treated with 10 mu g/ml cycloheximide for different durations, the blastocyst formation rate of oocytes treated for 5 h was significantly (P<0.05) higher than those of oocytes treated for 0-2 h. The blastocyst formation rate of oocytes treated with 10 mu g/ml cycloheximide for 5 h was significantly (P<0.05) higher than those of oocytes treated with 0-5 or 15-20 mu g/ml cycloheximide for the same duration. When oocytes were treated with different concentrations of cycloheximide for 2 h, however, the blastocyst formation rate of oocytes treated with 40 mu g/ml cycloheximide was significantly (P<0.05) higher than those of oocytes treated with 0-10 or 50 mu g/ml cycloheximide. The blastocyst formation rate of oocytes treated with 10 mu g/ml cycloheximide for 5 h was not significantly different from that of oocytes treated with 40 mu g/ml cycloheximide for 2 h. These treatments did not affect the activation status of oocytes con pared with controls that were not treated with cycloheximide. The results Of the present study showed that cycloheximide improves the parthenogenetic development of pig oocytes activated