Improvement of Sperm Quality in Cryopreserved Boar Semen by Supplementation of Kaempferia parviflora and Cholesterol-Loaded Cyclodextrin in Semen Extender

Abstract

We investigated the potential of Kaempferia parviflora (KP) extract, rich in phenolic compounds, for enhancing boar semen quality during cryopreservation. We evaluated the impact of various KP extract concentrations (0%–8% w/v) in freezing extenders on postthawed semen quality and oxidative stress markers, along with the effects of cholesterol-loaded cyclodextrins (CLC). Semen was frozen using liquid nitrogen vapor before being plunged into liquid nitrogen, and postthaw semen quality and lipid peroxidation were analyzed. Results showed that 2%–4% KP extract significantly improved total and progressive motility, sperm viability, and acrosome integrity compared to the control (p < 0.05), likely due to reduced lipid peroxidation indicated by lower malondialdehyde (MDA) levels (p < 0.05). However, higher concentrations (6%–8%) negatively affected sperm quality. Adding CLC further enhanced the positive effects of KP extract, improving sperm motility and acrosome integrity and reducing lipid peroxidation (p < 0.05). In conclusion, supplementation of boar semen cryopreservation media with 2% KP extract significantly enhanced sperm quality postthawing, likely through its potent antioxidant properties. Combining KP extract with CLC amplified these beneficial effects. These findings highlight a promising natural strategy for improving boar semen cryopreservation outcomes.