ABSTRACT
The present study attempted to investigate the effect of various concentrations of spirulina platensis additions to the semen extender on Arabian stallion spermatozoa quality. Semen samples were collected with artificial vagina from five fertile stallions and diluted with an extender containing spirulina (2, 4, 6, and 8 mg/100 mL) or without spirulina (control). Aliquots of diluted semen were cooled (5°C, 90 minutes) and frozen (-196°C, 7 days), then physical traits of thawed spermatozoa were examined. Furthermore, antioxidant activities of superoxide dismutase (SOD), glutathione reductase (GSR), total antioxidant capacity (TAC), and malondialdehyde (MDA) were measured in post-cooling and freezing spermatozoa. The results indicated that spirulina supplemented with the extender had no effect (P >.05) on sperm quality parameters and antioxidant activities after cooling. However, adding 6 mg spirulina/100 mL to the freezing extender improved (P < .05) the speed parameters and total motility percentage of frozen/thawed spermatozoa. Besides, supplementation of freezing extender with the previous level increased (P < .05) TAC, SOD and GSR concentrations/activities (0.86 ± 0.32 mM/L, 323.70 ± 12.81 U/mL, and 38.65 ± 1.90 U/mL, respectively) compared with the control (0.70 ± 0.25 mM/L, 165.80 ± 8.12 U/mL, and 25.70 ± 1.83 U/mL, respectively). While, lipid peroxidation of the frozen-thawed semen was reduced (P < .05, 17.97 ± 1.30 µmol/ L) compared with the control (29.39 ± 1.89 µmol/ L). Accordingly, the present results revealed that additions of 6 mg spirulina/100 mL to the freezing extender improved semen quality and reduced cryodamage of the Arabian stallion spermatozoa.
