Preservative Effects of Apple and Orange Juices on Refrigerated Kalahari Red Goat Spermatozoa

Abstract

Antioxidative mechanisms protect the sperm from the damage caused by free radicals and fruit-rich antioxidants are linked with improved viability of spermatozoa because of their protective effects against cell damage during preservation. This study investigated the effects of apple and orange juices on viability and lipid peroxidation (LPO) of refrigerated spermatozoa of Kalahari Red goats (KRG).  Pooled semen from five bucks was diluted with Tris-milk based extender supplemented with apple and orange juices (natural antioxidants) each at 0.0%, 2.5%, 5.0%, 7.5%, and 10.0%. The extended semen samples were assessed at 24 hours interval up to 216 hours for sperm motility, acrosome integrity, membrane integrity and sperm abnormalities using a Celestron Penta View LCD digital microscope after storage at 5 ^oC. The concentration of LPO in the stored semen was measured by determining the malondiadehyde in thiobarbituric acid reactive substances. The experimental design was a 2 x 5 x 10 factorial arrangement (2 antioxidants, 5 levels of inclusion and 10 duration of storage). Data were subjected to analysis of variance for the effects of each of the antioxidant source. The highest result of sperm progressive motility was obtained at 2.5% inclusion level of extender supplemented with apple juice (93.00%) at 24 hours of storage (P<=0.05). The extenders supplemented with 2.5% and 5.0% concentrations of apple and orange juices had consistently higher (P<=0.05) acrosome integrity commenced from 24 hours up to 216 hours of post-chilling compared to the control. The results showed consistent higher (P<=0.05) membrane integrity in extenders supplemented with fruit juices compared to the control and this was more pronounced in extenders supplemented with 2.5% and 5.0% of both apple and orange fruit juices after post-chilling. Inclusion levels at 2.5% and 5.0% had similar LPO reaction but the lowest occurred at 2.5% and 5.0% levels of inclusion(0.01%) of orange juice and the same result was obtained at 5.0% inclusion of apple but highest (0.10%) was recorded in the control (P<=0.05). The extenders supplemented with 2.5% apple and orange juices had consistently lower (P<=0.05) abnormality compared to the control. This study revealed that inclusion of apple and orange juices (natural antioxidants) used in Tris-milk based extender had protective effect on KRG spermatozoa viability.