Effect of methylxanthines on the cryopreservation of semen from bulls of the Argentine Creole breed

Abstract

The objective was to evaluate the use of caffeine and theophylline on the cryopreservation of semen from Argentine Creole bulls, studying their effects on motility, sperm vigor, and semen pH. Five clinically healthy and reproductively fit adult males were used. Five extenders were used: T1 (control): 11% lactose, T2: 6 millimoles (mmol) caffeine, T3: 10 mmol caffeine, T4: 6 mmol theophylline, and T5: 10 mmol theophylline. Semen samples were obtained using an Artificial Vagina. Macroscopic and microscopic evaluations were performed on each sample. They were then frozen and stored in liquid nitrogen for later observation, for which 5 straws from the same bull were thawed in a water bath at 37 ºC, then the dilution was performed in a 3:1 ratio (Diluent: semen) of each straw in a different treatment, then it was kept in a water bath at 37 ºC during the observation time. Observation was carried out at 0, 30, 60, 90 and 120 minutes post-thawing, evaluating sperm motility and vigor; pH was measured at time 0 and 120. The motility and vigor data obtained did not present statistically significant differences (p < = 0.05) at 30, 60 and 120 minutes, caffeine 6 mmol. had an effect (0 min) and theophylline at 90 min; Regarding vigor, theophylline 10 mmol showed an effect after 60 minutes, and the pH decreased after 120 minutes of observation in the samples containing methylxanthines.