A comparative study of parthenogenetic activation and in vitro fertilization of in vitro matured caprine oocytes

Document Type : Full paper (Original article)

Authors

1 Department of Surgery and Medical Pathology, School of Veterinary Medicine and Sciences, The University of Ngaoundere, Ngaoundere, Cameroon

2 Physiology Reproduction and Shelter Management Division, Central Institute for Research on Goats (CIRG), Makhdoom, Farah-281122, Mathura, Uttar Pradesh, India

Abstract

The aim of the study was to compare the parthenogenetic activation and in vitro fertilization (IVF) of in vitro matured caprine oocytes. A total of 881 cumulus-oocyte complexes (COC’s) were collected from 243 ovaries. Oocytes were matured in TCM-199 medium containing eCG (20 IU/ml), hCG (20 IUμg/ml), oestradiol-17β (1 μg/ml), BSA embryo tested (3 mg/ml) supplemented with 10% fetal bovine serum at 38.5°C and 5% CO2 in an incubator under humidified air for 27 h. Based on cumulus expansion, the maturation rate was 86.86%. Morphological matured oocytes (n=749) were selected, denuded and randomly divided into two groups.
Group 1 (n=223) in vitro matured oocytes activated with 5 μm calcium ionophore for 5 min and cultured in mCR2aa medium containing 5 mM DMAP for 4 h. After 4 h of DMAP treatment, the presumptive zygotes were washed and cultured in the embryo culture medium. Group 2 (n=526) in vitro matured oocytes processed for IVF in mTALP using fresh semen of a fertile pure bred adult Sirohi buck and in vitro culture in mCR2aa medium. Development of putative zygotes was observed every 24 h till day 9 post activation or fertilization under inverted phase contrast microscope. The cleavage rate, morula and blastocyst percentage in groups 1
and 2 were 67.36%, 23.07% and 9.23%, and 30.99%, 19.63% and 9.82%, respectively. The results indicated that the cleavage rate was comparatively higher following parthenogenetic activation with ionomycin/6-DMAP than IVF.

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