Effect of Royal Jelly on Viability and in vitro Maturation of Egyptian Sheep Oocytes in Serum Supplemented Medium

The present study was conducted to investigate the effects of addition of different concentrations (0.1, 0.2, 0.2, 0.4 and 0.5%, respectively) of Royal Jelly on the viability and maturation of the Egyptian sheep oocytes during in vitro culture of oocytes in serum supplemented tissue culture medium. Sheep ovaries were collected form local slaughterhouse and then COCs were recovered from visible antral follicles (2-6 mm) by aspiration method and randomly divided into 6 groups. Each group of oocytes was incubated in tissue culture media -199 (TCM-199) with 10% Fetal Calf Serum (FCS) with different doses of royal jelly (RJ). The treatments were: Control 0%, RJ 0.1%,RJ 0.2%, RJ 0.3%, RJ 0.4 ,RJ 0.5%, for 24-28 h at 39 oC under 5% CO2 in air and 95% humidity. Following the culture period, COCs were evaluated for morphology of cumulus expansion and viability by trypan blue exclusion test to investigate the effect of RJ on viability, cumulus expansion and in vitro maturation of sheep oocytes. The results indicated that the oocytes showing morphologically cumulus full expanded and lived increased significantly with RJ supplementation in a dosedependent manner up to 0.4%. The proportion of oocytes showing morphologically cumulus full expanded and lived oocytes was higher for all the supplements compared to control media. Following 24-28 h of oocyte culture in 10% FCS with TCM-199 containing various concentrations of RJ [0.1% (75%), 0.2% (80%), 0.3% (85%), 0.4% (94%) and 0.5% RJ (94%] resulted in higher maturation rate (p<0.05) rate than the control (60%). Therefore, the present study demonstrated that the addition of RJ to culture media could significantly improve the viability and in vitro maturation of sheep oocytes. Key word: Maturation, oocytes, ovine, royal jelly, viability