Assessing sperm motility in thawed bovine semen following prostaglandin F2α treatment

To improve the success of insemination, various substances are added to the insemination portion. However, the literature shows inconsistent results from this practice. Thus, the objective of the study was to quantify the effect of prostaglandin F2α (PGF2α) on the movement of frozen and thawed bovine sperm in vitro. 30 Ejaculate samples from 10 bulls of the race German Holstein (3 replicates from each bull) were thawed and treated each immediately with different concentrations (0.075, 0.250 and 5 mg) of PGF2α with the active substances cloprostenol-enantiomer, cloprostenol-racemate and dinoprost, respectively. Control treatment was assessed using no PGF2α additions. The motility characteristics of incubated cryopreserved-thawed sperm were evaluated repeatedly after 2, 4, 6, 8, 10, 12 and 24 h storage at 24 °C using computer-assisted system analysis. The results show a significant decrease in the percentages of total motility of bovine sperm when cloprostenol-racemate (p = 0.0010) and cloprostenol-enantiomer (p = 0.003) is used. A similar negative effect was observed using cloprostenol in racemate (p = 0.0021) and enantiomer (p = 0.013) forms for progressive motility. Regarding the velocity parameters, the observed data significantly indicate a decreasing effect in motion quality, when the thawed sperm treated with PGF2α compared to control group, except in distance curved line and curvilinear velocity significantly which indicated an improvement. Finally, no significant variations were found in the global variance analysis between time and concentration, except for the progressive motility. The motion properties deteriorated with extended storage times over time. However, the racemate and enantiomer compounds significantly increased the VCL after thawing and 2 h of storage, a difference that was less apparent during the investigation. In conclusion, the results suggest that the addition of higher concentrations of PGF2α in vitro to cryopreserved-thawed bovine sperm has a significantly negative effect on sperm motion characteristics. However, lower levels of PGF2α either have no effect or slightly improve kinetic parameters. In addition, It cannot be assumed that the addition of PGF2α during insemination has a positive effect on the achieved results.