Studies On Extenders For Bull Semen Crypreservation

The present study was carried out to improve the efficiency of bull semen crypreservation with different compositions of extenders. The results of the experiments were as followings.1. Effect of different buffers in the freezing extender on frozen-thawed semen was investigated. There were no significant difference in motility, moving speed, recovery rate, abnormality rate and acrosome integrity rate of frozen-thawed spermatozoa among the following three buffered media groups: Citrate, TCA and Hepes, however the Hepes buffer gained the best result.2. When the extender was supplemented with 0.1% or 0.15% SDS, the progressive motility of the frozen-thawed spermatozoa was significantly improved comparing to the control group. When the extender was supplemented with 0.15% SDS, the recovery rate and acrosome integrity rate of the frozen-thawed spermatozoa were enhanced comparing to the control. Supplementation of 0.15% SDS gained the best result among all treatments.3. The effect of different storage time (0,12, 24, or 48 h) of diluents before freezing on crypreservation of spermatozoa was investigated. Prolonged storage(12, 24, or 48 h) of diluent improved the progressive...