MJAS

Manuscript Details

Comparison of Bovine Embryonic Development of Parthenogenetically Activated Oocytes by Different Combinations of Chemical Treatments

Siti Khadijah, I., Rahman, M. M., Abdullah*, R. B. and Wan Khadijah, W. E.

Animal Biotechnology-Embryo Laboratory (ABEL), Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.

Malaysian J. Anim. Sci. 2014 17(1): 85-94

Click to view the abstract

Oocyte activation is the efficient method or step for successful animal cloning. This study was carried out to evaluate the embryonic development for both parthenotes and fertilised embryos according to the oocyte grades (Grades A, B and C). Recovered oocytes according to the oocyte grades were divided into various combination treatments: (i) A23187+6-DMAP, (ii) Iono+6-DMAP, (iii) EtOH+6-DMAP, (iv) Iono+CHX, and (v) IVF (control). Treatment with combination of 10 ?M Iono+2 mM 6-DMAP indicated the highest embryonic development rates for 8-cell, morula and blastocyst stages compared to the other combination treatments. There were significant differences between combination of Iono+6-DMAP and IVF control at morula (24.3 vs. 3.4%) and blastocyst stages (7.1 vs. 0.0%), respectively. There was no consistent relationship between oocyte grades and embryo development rates. The data also showed that no differences were observed in blastocyst rates for each oocyte grade for all activation treatments including IVF control. In conclusion, to activate bovine oocytes for later embryonic development stages (8-cell, morula and blastocyst), the best combination treatment obtained in this study was the combination of 10 ?M Iono (5 min)+2 mM 6-DMAP (4 h), regardless of the grades of oocytes, including the importance of the optimal combination of chemical activation to produce bovine embryos in vitro.