Effects of electric stimulation on bovine oocyte activation and embryo development in intracytoplasmic sperm injection procedure.
OBJECTIVE
This study was carried out to investigate the efficacy of electric stimulation before and/or after intracytoplasmic sperm injection (ICSI) on bovine oocyte activation and embryo development.


METHODS
The oocytes were treated with electric shock before (B), before and after (B&A), and after (A) sperm injection. In each group, sham ICSI (ICSI-s) was performed to exclude the effect of parthenogenesis (B ICSI-s, B&A ICSI-s, and A ICSI-s). An electric pulse was applied with a single direct current (DC) pulse (0.8 kV/cm, 70 microseconds).


RESULTS
One pronucleus (PN) formation in the B&A ICSI-s group was slightly higher than that found in B and B&A ICSI group; however, the difference was not significant. Two PN formation in B&A ICSI group was higher than that found in sham ICSI groups (P < 0.05). There were no differences among treatment groups in the cleavage rate; however, morulae and blastocyst formation in the B&A embryos was significantly higher than that of other groups (P < 0.05) and got pregnant.


CONCLUSIONS
Electric stimulation before and after injection was an effective method in inducing bovine oocyte activation and in sustaining embryo development to the morulae and blastocyst stage.
Hwang
S
S
Infertility Clinic, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Lee
E
E
Yoon
J
J
Yoon
B K
BK
Lee
J H
JH
Choi
D
D
D000818:Animals; D001755:Blastocyst / Q000502:physiology; D002417:Cattle; D002478:Cells, Cultured; D004558:Electric Stimulation; D004624:Embryo Transfer; D005314:Embryonic and Fetal Development; D005260:Female; D008297:Male; D009028:Morula / Q000502:physiology; D009865:Oocytes / Q000502:physiology*; D011247:Pregnancy; D012661:Semen / Q000378:metabolism; D020554:Sperm Injections, Intracytoplasmic