Parisa Alipoor Janafard
Hosein Daghigh Kia
Gholamali Moghadam
Marzieh Ebrahimi

Effects of caffeine as metabolism enhancer agent with different concentration have studied on the motility parameters, longevity, total abnormalities and plasma membrane integrity of Ghezel ram spermatozoa after cryopreservation. Ram semen samples were collected and were diluted in Tris based extender with 1.5% lecithin and 7% glycerol divided in to five equal fractions, then caffeine was added at 0, 0/5, 1, 2 and 4 mM/L concentrations in different fractions. After cooling of diluted semen samples they were kept in liquid nitrogen until evaluations. Samples were thawed at 37°C for 30 sec and motility parameters, membrane integrity, longevity and total abnormalities were evaluated. To analyze the obtained data, we first examined them in terms of normality. Then data analysis was performed with SAS software (9.4) using GLM procedure. Theresults showed that addition of 0.5 and 2 mM/L caffeine increased straight line velocity (VSL), curvilinear velocity (VCL), linearity (LIN) and average path velocity (VAP) parameters in comparison with the control and other groups (P<0.05). Sperm abnormality was significantly decreased in group receiving 2 mM/L caffeine (P<0.05). Sperm viability was increased in group receiving 1 mM/L compare to the other groups (P<0.05). However, the addition of caffeine had no significant effect on the total and progressive motility and plasma membrane integrity. The results of this study showed that the addition of 0.5 and 2 mM/L caffeine in Tris-lecithin based extender can improve the quality and motility characteristics of freeze-thawed semen.

Cryopreservation, Caffeine, Motility characteristics, CASA