Effect of Spirulina platensis extract (C-phycocyanin) supplementation to the semen extender on kinematic and oxidative parameters of Marwari stallions during freezing.

The current research aimed at examining the impact of different quantities of Spirulina platensis extract (C-phycocyanin) supplemented to the semen extender on the post-thaw quality of Marwari stallion spermatozoa. Semen samples were obtained via an artificial vagina from six fertile stallions and diluted with an extender containing Spirulina platensis extract (C-phycocyanin) at concentrations of 10, 20, and 50 µg/mL, or without Spirulina as a control. Aliquots of diluted semen were subjected to cooling (4 °C, 120 min) and then frozen (-196 °C, 1 day), after which the kinematic parameters (VAP - average path velocity, VCL - curvilinear velocity, VSL - straight line velocity, STR - straightness, and LIN - linearity) as well as antioxidant activities of superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and malondialdehyde (MDA) were assessed in cryopreserved spermatozoa. The findings showed that Spirulina, when combined with the extender, significantly enhanced (P < 0.05) sperm kinematic characteristics and antioxidant activities post-freezing. Nonetheless, the incorporation of 50 µg C-phycocyanin/150 million spermatozoa into the freezing extender enhanced (P < 0.05) the motility metrics and antioxidant activities of frozen/thawed spermatozoa. The current findings indicated that the inclusion of 50 µg C-phycocyanin/150 million spermatozoa in the freezing extender enhanced semen quality and decreased cryodamage to Marwari stallion spermatozoa.