Influence of trans‐ferulic acid on the quality of ram semen upon cold preservation

BACKGROUND: Due to lower antioxidant capacity and higher amounts of polyunsaturated fatty acids, ram spermatozoa are very susceptible during cooling process. OBJECTIVES: The objective was to examine the effect of the trans‐ferulic acid (t‐FA) on the ram semen during liquid preservation. METHODS: Semen samples were collected from the Qezel rams, pooled, and extended with the Tris‐based diluent. Pooled samples enriched with different amounts of the t‐FA (0, 2.5, 5, 10, and 25 mM) and preserved at 4°C for 72 h. Spermatozoa's kinematics, membrane functionality, and viability were assessed by CASA system, hypoosmotic swelling test, and eosin‐nigrosin staining, respectively. Moreover, biochemical parameters were measured at 0, 24, 48, and 72 h. RESULTS: Results showed that 5 and 10 mM t‐FA improved forward progressive motility (FPM) and curvilinear velocity compared to the other groups at 72 h (p < 0.05). Samples treated with 25 mM t‐FA showed the lowest total motility, FPM, and viability at 24, 48, and 72 h of storage (p < 0.05). Higher total antioxidant activity levels were observed in the 10 mM t‐FA‐treated group compared to the negative control at 72 h (p < 0.05). Treatment with 25 mM t‐FA increased malondialdehyde amounts and decreased superoxide dismutase activity compared to other groups at the final time assessment (p < 0.05). Nitrate‐nitrite and lipid hydroperoxides values were not affected by treatment. CONCLUSIONS: The current study indicates the positive and negative influences of different concentrations of t‐FA on the ram semen upon cold storage.