Protective effects of Tribulus terrestris and Cinnamomum zeylanicum extracts and trehalose added to diluents on goat epididymal sperm freezability

This study investigates the effect of adding Tribulus terrestris ethanol extract (TEE) and Cinnamomum zeylanicum ethanol extract (CEE) and trehalose on freezability of goat epididymal spermatozoa. In Experiment 1, the treatments consist of basic extender containing 25, 50 or 100 mu g/ml of TEE or CEE. The control contained no additives. Experiment 2 was carried out to compare the effect of best concentrations resulted in the first experiment with 150 mM trehalose added to basic extender. The results of experiment 1 showed that supplementation of 50 mu g/ml TEE and 50 mu g/ml CEE increased significantly the percentages of motility, progressive motility and viability of cryopreserved spermatozoa, while the level of malondialdehyde concentration was decreased. Moreover, the 50 mu g/ml TEE treatment indicate significantly) P < 0.05) the lowest DNA fragmentation among the other treatments. The data obtained from experiment 2 show that all treatments increased significantly) P < 0.05) the percentages of total motility, viability and membrane integrity, and concurrently decreased the rate of MDA compared to control. In addition, the rates of viability and progressive motility were significantly (P < 0.05) higher in diluents contained herb extracts and trehalose. Regarding DNA fragmentation, the results demonstrate that using the extracts and trehalose in diluents decreased the DNA damages and thereby improved the rate of intact sperm heads. In conclusion, the results of this study indicate that 50 mu g/ml of Tribulus terrestris and Cinnamomum zeylanicum ethanolic extracts alone and plus trehalose improved the spermatozoa quality and could be used for cryopreservation.