P-9: Effect of Lyophilized LDL and Different Levels of Clove Bud Extract on The Quality of Cryopreserved Ram Semen

Background: Low density lipoprotein (LDL) of egg yolk has been successfully used for stallion and bull semen cryopreservation. However, there is limited information to clarify the effect of LDL or lyophilized LDL on ram semen quality. On the other hand, during semen collection, dilution and cryopreservation we need to protect the spermatozoa from lipid peroxidation. Clove bud has polyphenolic compounds with powerful antioxidant properties. So the objective was to evaluate the cryoprotective effect of lyophilized LDL and different levels of clove bud extract added to ram semen extender. Materials and Methods: Semen samples were collected from three mature Iranin rams (3-4 years old and 105 kg BW) by using an artificial vagina twice a week during the breeding season. The semen samples were diluted with extenders containing 15% egg yolk (as control) or 8% lyophilized LDL. The levels of clove bud extract added to the extender were 0, 35, 75, and 115 mg/ml. Results: This study demonstrated that extender with lyophilized LDL had adverse effects on motility and viability of spermatozoa before freezing (p <0.05), but there was no significant difference between the two group after thawing. Different levels of clove bud extract affect the sperm quality before and after cryopreservation (p<0.05). Conclusion: It was concluded that 15% egg yolk had better performance than 8% lyophilized LDL in semen extenders in before freezing and the best level for clove bud extract was 75 mg/ml.