Abstract
This study evaluated the effect of melatonin supplementation of in vitro maturation media on in vitro maturation (IVM) and in vitro fertilization (IVF) rate of buffalo oocytes. Cumulus oocytes complexes (COCs) were aspirated from follicles of 2-8mm diameter. In experiment I, COCs were matured in IVM medium supplemented with 0 (control), 250, 500, and 1000 µM melatonin for 22-24 hours in CO2 incubator at 38.5 oC with 5% CO2 and at 95% relative humidity. The maturation rate did not differ in media supplemented with melatonin at 250 µM, 500 µM, 1000 µM and control (0 µM). In experiment II, the matured oocytes were fertilized in 50 µl droplets of Tyrodes Albumin Lactate Pyruvate (TALP) medium having 10ug/ml heparin for sperm (2 million/ml) capacitation. The fertilization droplets were then kept for incubation at 5% CO2, 39 oC and at 95% relative humidity for 18 hours. The fertilization rate was assessed by sperm penetration and pronuclear formation. Fertilization rate was improved when maturation medium was supplemented with 250 µM melatonin compared to control. In conclusion, melatonin supplementation to serum free maturation media at 250 µM improved the fertilization rate of buffalo oocytes.
Key words: Buffalo, In vitro fertilization, In vitro maturation, Melatonin
