Effect of medium type and luteinizing hormone (LH) on in vitro maturation of Egyptian buffalo oocytes
This study was carried out to evaluate the maturation of buffalo oocytes in vitro. In the first experiment, oocytes were cultured for 22 to 24 h in TCM-199, CR1aa and mSOF with or without luteinizing hormone (LH). Results show that all media with LH were better than media without LH; maturation rate was low in mSOF without LH and high in TCM–199 and CR1aa with LH. Moreover in comparison, TCM–199+LH with CR1aa + LH, 1282 oocytes were cultured. Maturation rate was assessed by evaluation of degree of cumulus cells expansion and meiotic development. Results indicate that recovery rate ranged between 2.4 to 2.8. Moreover, results revealed that maturation rate, telophase and metaphase II stages were higher for oocytes matured in TCM-199 + LH than oocytes matured in CR1aa + LH. In the second experiment, oocytes were matured in vitro in TCM 199+LH for investigating the effect of oocytes quality (excellent, good and denuded) and culture system (single or group). Excellent oocytes and group culture system were significantly higher in maturation rate and metaphase II stage. In conclusion, using TCM-199+LH, excellent oocytes and group culture system resulted in an increase of oocytes matured in vitro.
Key words: LH, In vitro maturation, Egyptian buffalo, types media.