eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2015-08-15 12 2 1151 1156 2304 article Hashemi Seyede Sara 1 Rafati Ali Reza 2 Shiraz Burn Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran Department of Pharmacology, Islamic Azad University, Sarvestan Branch, Sarvestan, Iran Different media have been introduced and experienced in in vitro maturation of oocytes. The aim of this study was to compare three culture media for in vitro maturation (IVM) of bovine oocytes. Ovaries collected in Fars slaughter house (Barmshur) are the main source of oocytes for IVM and in vitro fertilization (IVF) studies. Bovine ovaries were collected in a local slaughter house and transported to the laboratory. Oocytes were aspirated from the follicle and washed 4 times in TCM-199. 1820 compact cumulus oocytes complexes (COCs) were aspirated from ovaries. Oocytes were randomly cultured in the first controlled medium consisted of TCM-199, HCG, follicular fluid (FF) and antibiotic. In the second and third media, different concentrations (10, 15 and 20%) of rat estrous serum (RSS) or estrous sheep serum (ESS) was added to controlled media respectively. Oocytes were incubated at 38.5°C, an incubator containing 5% CO₂ and 95% humidly for 24 hours. The maturation of oocytes was jugged according to cumulus cell expansion or observation of polar body in randomly orcein stained oocytes. The result of this study showed that maturation rate was significantly higher in second and third groups in comparison with controlled one (p<0.05). There was no significant controlled difference between second and third groups.   https://www.biotech-asia.org/vol12no2/effects-of-different-concentrations-of-serums-on-in-vitro-maturation-of-bovine-oocytes/ Bovine; Rat estrus serum; Estrous sheep serum; Oocyte maturation; Ovary