Removing the cumulus cells of caprine oocytes by using hyaluronidase enzyme

Abstract

This study was performed to determine a convenient method for removing the cumulus cells of caprine oocytes by using hyaluronidase enzyme. Caprine oocytes were matured in TCM-199 supplemented with 0.25 mM sodium pyruvate, 10% (v/v) fetal bovine serum (FBS), 0.05 μg/m follicle stimulating hormone (FSH), 05 μg/ml luteinizing hormone, 01 μg/ml estradiol, 39^oC, 5% CO₂ in humidified air for 32 hours. Subsequently, matured oocytes were transferred into TCM-199Hepes of differing conditions: a/ Hyaluronidase concentration (0.2; 0.5; 1.0 and 1.5 mg/ml); b/ Temperature of medium (32, 37 and 40^oC); c/ Treatment time (30, 60, 90, 120 and 180 seconds). The efficiency of removing cumulus cells using hyaluronidase enzyme and pipeting for 120 seconds, 18 seconds were found convenient methods (85.25% and 86.79% respectively). These results were significantly higher (P<0.05) than those obtained when pipetting was carried out for 90 seconds (43.14%). In conclusion, the best conditions for removing the cumulus cells of matured caprine oocytes to be involved the use of hyaluronidase enzyme (1.0 mg/ml ; 37^oC, 120 - 180 seconds) combined mechanically (by pipeting using glass capillary with 130 - 150 μm inner diameter).