Korean Journal of Agricultural Science ISSN:2466-2402(Print) 2466-2410(Online) 농업과학연구

Shilajit is a dark-brown exudate found in the rock formations of the Himalayas and contains various minerals, vitamins, and enzymes. The present study was performed to examine sperm motility, sperm adenosine triphosphate (ATP) content, generation of reactive oxygen species (ROS), and calcium ion (Ca2+) levels after exposure of sperm to shilajit. In the presence of various concentrations of shilajit, in vitro fertilization (IVF) of pig oocytes occurred with a reduced incubation time (3 hrs) and low sperm number (1 × 105 sperm·mL-1). The percentage of hyperactive sperm significantly increased with 10 and 20 μg·mL-1 shilajit (p < 0.05). A significant number of intact acrosomal sperm were observed in sperm with 10 - 50 μg·mL-1 shilajit (p < 0.05). In addition, higher adenosine triphosphate (ATP) content was observed in sperm exposed to these concentrations of shilajit compared to sperm incubated at 100 μg·mL-1 shilajit or without shilajit (p < 0.05). When sperm were incubated with shilajit, the generation of ROS decreased compared to sperm without shilajit, and an increment of cytoplasmic Ca2+ was observed in sperm exposed to 10 and 20 μg·mL-1 shilajit (p < 0.05). In IVF trials, the sperm rapidly reached the oocytes in the presence of shilajit, and significantly higher total fertilization was observed in the IVF medium with 10 and 20 μg·mL-1 shilajit. In conclusion, shilajit was seen to have a beneficial effect on improving sperm penetration and fertilization, suggesting that it could be a potential agent to improve fertilization rates in cases of subfertility and infertility during assisted reproduction.