The effects of thawing temperatures on sperm plasma membrane functional integrity and sperm morphology after SWIM-UP and percoll gradient

ABSTRACT THE EFFECTS OF THAWING TEMPERATURES ON SPERM PLASMA MEMBRANE FUNCTIONAL INTEGRITY AND SPERM MORPHOLOGY AFTER SWIM-UP AND PERCOLL GRADIENT In recent years, in vitro embryo production from reproductive biotechnologies has been widely used in cattle and continues to increase day by day. In this context, the importance of semen quality used in the in vitro fertilization phase is also increasing. The aim of the present study is to compare the frozen semen of Brown Swiss breed thawed in 37°C/30 sec, 50°C/15 sec, and 70°C/5 sec water bath with the experimental groups, separated by Percoll and Swim-up separation methods, and the control group without any separation process. In this way, the effects of Percoll and Swim-up methods on sperm motility, dead and viable ratios, acrosomal structure, and plasma membrane integrity are examined. At 37°C/30 sec, 50°C/15 sec and 70°C/5 sec thawing conditions, the mean FITC-PSA values were 32.35%, 41.35% and 56.30% in the Percoll group; 25.25%, 32.45% and 63.90% in the swim-up group; 17.90%, 18.35% and 17.45% in the control group, respectively. Dead cell rates at the same temperatures were 31.38%, 14.95% and 30.65% in the Percoll group; 15.85%, 13.60%, and 13.50% in the Swim-up group; 35.58%, 46.18%, and 35.82% in the control group, respectively. In addition, at the same temperatures, viable cell rates were 68.63%, 85.05%, and 69.35% in the Percoll group; 69.15%, 86.40%, and 86.50% in the Swim-up group; 68.43%, 53.83%, and 64.18% in the control group, respectively. Furthermore, at the same temperatures, the motility rates were 55.75%, 58.50%, and 48.25% in the Percoll group; 59.75%, 55.75%, and 54.75% in the Swim-up group; 49.25%, 45.75%, and 48.75% in the control group, respectively. Lastly, at the same temperatures, the HOST results were 73.95%, 69.50%, and 42.20% in the Percoll group; 77.55%, 72.00%, and 50.15% in the Swim up group; 62.65%, 70.50%, and 50.60% in the control group, respectively. As a result, it was concluded that 37°C would be the optimum temperature in order to benefit from semen separation methods when applying assisted reproductive techniques, to make the thawing process practical, and to avoid the negative effects that may arise from the prolongation of the thawing process. Key Words: Bull, Sperma, Percoll, Swim-up, Temperature