Research note: Improving post-thaw rooster sperm quality with Eurycoma longifolia extract and cyclodextrin.

Cryopreservation of rooster semen is essential for genetic conservation and breeding programs; however, the current methods result in a significant loss of viability. This study investigated the potential of Eurycoma longifolia (EL) extract and its cyclodextrin complex (EL-loaded cyclodextrin [ELC]) to improve rooster sperm cryopreservation. Supplementation with EL extract at 4 mg/mL significantly increased post-thaw total motility (62.84 ± 4.45 %), progressive motility (32.70 ± 2.48 %), viability (55.90 ± 0.72 %), and decreased MDA (2.98 ± 0.41 nmol/mL) compared to controls (P < 0.05). ELC (2 mg/mL) resulted in greater improvements in total motility (59.21± 1.03 %), progressive motility (38.46± 1.43 %), and viability (58.11± 0.58 %), and lower MDA levels (2.60 ± 0.04 nmol/mL) compared to control (P < 0.05). Both EL and ELC significantly improved fertility (55.38± 1.26 % and 52.19 ± 1.09 %, respectively; P < 0.05). These results highlight the potential of EL and ELC for optimizing cryopreservation protocols.