Korean Journal of Agricultural Science (Korean J. Agric. Sci.; KJOAS)
Indexed in KCI (Korea Citation Index), Open Access, Peer Reviewed.
pISSN 2466-2402
eISSN 2466-2410

The pesticide metabolite fipronil sulfone diminishes the fertilizing capacity of boar spermatozoa



Adikari AADI, Yi YJ. The pesticide metabolite fipronil sulfone diminishes the fertilizing capacity of boar spermatozoa. Korean Journal of Agricultural Science 50:87-97.

Korean Journal of Agricultural Science (Korean J. Agric. Sci.) 2023 March, Volume 50, Issue 1, pages 87-97. https://doi.org/10.7744/kjoas.20230005

Received on 02 January 2023, Revised on 03 January 2023, Accepted on 14 February 2023, Published on 30 March 2023.

The pesticide metabolite fipronil sulfone diminishes the fertilizing capacity of boar spermatozoa

Adikari Arachchige Dilki Indrachapa Adikari, Young-Joo Yi*

Department of Agricultural Education, College of Education, Sunchon National University, Suncheon 57922, Korea

*Corresponding author: yiyj@scnu.ac.kr


Fipronil sulfone (FS) is known to adversely affect the organs and organ systems of all living organisms exposed to this substance. The present study was performed to examine the effects of FS on the fertilizing capacity of boar spermatozoa. The boar sperm samples were subjected to varying concentrations of FS (10 – 200 µM) for two different incubation times (30 min and 2 hrs). Sperm motility, viability, acrosome integrity, and production of intracellular reactive oxygen species (ROS) were then evaluated. Real-time PCR was conducted to analyze the RNA expression of ODF2, ZPBP2, HSPA8, and AKAP4, which are associated with the integrity of the sperm fibrous sheath and sperm movement. A dose-dependent motility reduction was observed in sperm exposed to FS during both incubation periods compared to the controls. Higher percentages of viable sperm were observed in the controls, while viability was significantly decreased in sperm incubated with 20 – 200 µM FS. Acrosomes were damaged in sperm incubated with 200 µM FS after 30 min of incubation. Higher levels of intracellular reactive oxygen species (ROS) were produced in sperm exposed to FS after 2 hrs of incubation. Also, the mRNA expression levels of ODF2, ZPBP2, and AKAP4, which are associated with fertilizing capacity, were downregulated in sperm exposed to FS compared to the controls. Direct exposure to metabolites of specific pesticides such as fipronil affects male fertility due to their effects on sperm characteristics. It is thus necessary to screen metabolites that cause reproductive physiotoxicity to protect health and prevent sub-/infertility in animals.


boar, fertilization, fipronil, pesticide metabolites, spermatozoa


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Authors Information

Adikari Arachchige Dilki Indrachapa Adikari, https://orcid.org/0000-0002-1021-3814

Young-Joo Yi, https://orcid.org/0000-0002-7167-5123


This paper was supported by Sunchon National University Research Fund in 2022 (Grant number: 2022-0305).

Conflicts of interest

No potential conflict of interest relevant to this article was reported.