Cryopreservation of South African indigenous goat semen
The aim of this study was to cryopreserve and evaluate frozen-thawed semen parameters. Electroejaculator was used to collect semen from six bucks. Semen samples were divided into two parts. In one part, seminal plasma was removed and was not in the other one. Both semen sample parts were extended with egg-yolk Tris extender. Semen was thereafter cryopreserved in straws using liquid nitrogen. Data were analysed using Stata® V10 software. South African indigenous goats had total sperm cell motility rate of 83.1%, progressive sperm cell motility of 49.3% and non-progressive sperm cell motility of 33.9%. Moreover, acidic semen pH of 6.4 and low sperm cell concentration (663.6 × 106/ml) were obtained. Removal of seminal plasma and semen cryopreservation significantly decreased pH (5.8 ± 0.1 and 5.7 ± 0.1 for frozen-thawed washed and not-washed, respectively) and sperm cell motility rates of South African indigenous goats. Reduction in the sperm cell motility after freeze/thawing is still a problem and requires further research on the diluents and techniques that give protection to sperm cells during cryopreservation.
Key words: Cryopreservation, semen characteristics, indigenous goat.