Effect Egg Yolk in CEP Extender for Sperm Capacitation of Bull During Storage at Temperature 4-5 °C

The existence of reactive oxygen species (ROS) during spermatozoa storage can cause damage to the plasma membrane and DNA. But in small amounts, ROS can induce capacitation events required for fertilization ability. This study aimed to assess the effect ROS on acrosome capacitation of Limousin bull spermatozoa after stored in the CEP diluent containing egg yolk compared with no egg yolk. Limousin bull semen was obtained from three different cows, diluted with CEP with and without egg yolk supplementation, then stored at a temperature of 4-5 degrees C. ROS generation was measured by increased activity of SOD. Acrosorne capacitation status was measured by using chlortetracycline (CTC) fluorescence. The results showed the increasing of SOD activity both on the spermatozoa are stored in the CEP with and without egg yolk supplementation. However, the activity of SOD in egg yolk diluent CEP without significantly lower than the CEP with egg yolk. The existence of ROS in CEP extender without egg yolk has induced capacitation (62.59 +/- 2.91), significantly higher than in CEP extender without egg yolk (38.74 +/- 9.86). The conclusion was egg yolk supplementation in CEP extender has provided protection spermatozoa from the influence of ROS, so that acrosome physiological status can still be maintained during storage at a temperature of 4-5 degrees C.