Shilajit improves sperm penetration on In vitro fertilization of pig oocytes

Young-Joo  Yi1,*   Wijesooriya Mudhiyanselage Nadeema  Dissanayake1   Ram Prasad  Aganja2   Sang-Myeong  Lee3   

1Department of Agricultural Education, College of Education, Sunchon National University, Suncheon 57922, Korea
2Division of Biotechnology, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan 54596, Korea
3Laboratory of Veterinary Virology, College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Korea


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.

Figures & Tables

Fig. 1. Comparison of the motility of sperm exposed to varying concentrations of shilajit. After incubation in the presence of shilajit, sperm motility (A), progressive sperm (B), and hyperactive sperm (C) were measured using a computer-assisted sperm analysis system (CASA). Values are expressed as mean ± standard error of the mean (SEM). a, b: Different superscripts in each column indicate significant differences at p < 0.05