Recongelación de espermatozoides bovinos como alternativa para mejorar la calidad espermática de semen descongelado.

Abstract

The objective was to evaluate the effect of re-freezing bovine sperm on the sperm quality of thawed semen. For this, the semen was thawed in water at 56oC for 12 seconds to simulate a maximum seminal aggression, the content of the straws was poured into test tubes to keep them temperate at 37oC and incubated with 5 ml of Tyrode medium for 15 minutes. After this time, the microscopic analysis of the semen was carried out, two centrifugations were carried out 300 rpm / 5 minutes - 800 rpm / 10 minutes and the sperm concentration was determined with the help of a digital cell counter to dilute the semen. The stabilization and conditioning of the sperm was carried out at room temperature (14-20o C) for 45 minutes and under ultraviolet light, then the straws were packed and sealed using 0.5 ml straws and polyvinyl alcohol to seal them. The temperature curves and finally the refreezing in nitrogen vapors were carried out. For hypothesis testing, the analysis techniques of ADEVA (Analysis of Variance) and separation of measurements by the Waller Duncan multiple range method were used at a significance level of p <0.01. It was thus determined that in the evaluated parameters the reconfrozen semen showed better results as in the DNA damage where it was determined that the reconfrozen semen presented less damage with 1.07% in contrast to the frozen semen which presented 8, 74% damage. When analyzing the different variables of re-frozen semen, it was determined that the effect of this biotechnology is positive in variables such as DNA damage and sperm membrane damage, having values lower than those reported in frozen semen; this indicates that when sperm is re-frozen, sperm quality improves especially in the mentioned variables. It is recommended to use re-frozen sperm in reproductive biotechnologies such as In Vitro Fertilization.