Original scientific paper

Effect of epidermal growth factor on maturation and fertilization in vitro of goat follicular oocytes in a serum free or serum supplemented medium

Dhanraj Nagar ; Department of Animal Reproduction, Gynaecology and Obstetrics, College of Veterinary and Animal Science Rajasthan Agricultural University, Bikaner, India
Govind Narayan Purohit ; Department of Animal Reproduction, Gynaecology and Obstetrics, College of Veterinary and Animal Science Rajasthan Agricultural University, Bikaner, India

Abstract

The cumulus expansion, nuclear maturation and fertilization of goat cumulus oocyte complexes (COC) were studied during in vitro culture, either in serum supplemented or serum free tissue culture medium (TCM- 199) to which different concentrations (10, 20, 50 and 100 ng ml-1) of epidermal growth factor (EGF) were added. There were two experiments with different end points: (1), Cumulus expansion and nuclear maturation after 28 h of culture (8 replicates), and (2), Proportion fertilized 24 h after insemination (8 replicates). Oocytes
were cultured in groups of up to five per drop. In Experiment 1, the cumulus expansion of oocytes increased signifi cantly with EGF supplementation in a dose-dependent manner up to 50 ng ml-1. However, there were no differences in serum free or serum supplemented medium. The proportion of oocytes showing +++ cumulus expansion was higher for all the supplements compared to control media. However, the dose dependent effect of EGF supplementation in increasing the proportion of oocytes reaching metaphase II was evident only up to 20 ng ml-1. Supplementation of EGF resulted in a signifi cantly (P<0.01) higher proportion of oocytes reaching M II compared to control. The respective proportion of oocytes that reached M II were 55.63%, 64.5%, 52.35%, 49.18% and 34.07% in media supplemented with 10, 20, 50, 100 and 0 (control) ng/ml of EGF. In experiment 2 EGF supplemented media had a signifi cantly (P<0.01) higher proportion of oocytes that were fertilized in vitro compared to control. The supplementation of EGF increased the fertilization rates in oocytes in a dose-dependent manner up to 50 ng/ml. Serum supplementation had no effect on fertilization in vitro of goat COC’s. It was concluded that EGF at concentrations of 10 to 50 ng/ml increase the in vitro maturation and fertilization of goat COC’s. Addition of serum to EGF supplemented media had little benefi t in increasing the maturation and
fertilization in vitro of goat COC’s.

Keywords

epidermal growth factor; goat; in vitro fertilization; oocytes; serum

Hrčak ID:

25198

URI

https://hrcak.srce.hr/25198

Publication date:

20.12.2005.

Article data in other languages: croatian

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