AMERICAN JOURNAL OF VETERINARY RESEARCH, cilt.87, ss.1-10, 2025 (SCI-Expanded, Scopus)
This study evaluated the relationship between postthaw A-kinase anchoring protein 4 (AKAP4) fluorescence intensity and spermatological parameters in cryopreserved goat semen.
Semen was collected weekly by electroejaculation during the nonbreeding season, diluted, and cryopreserved using an automated freezing system. Postthaw sperm were assessed for total motility, progressive motility, and kinematics using computer-assisted semen analysis. Flow cytometry evaluated plasma membrane and acrosome integrity, high mitochondrial membrane potential, viability, and oxidative stress. The AKAP4 localization was determined by immunofluorescence, and intensity (X103 arbitrary units) was measured in 300 sperm/sample. Cluster analysis examined categorical effects of AKAP4 intensity (low, medium, and high), and correlations assessed continuous effects.
Ninety ejaculates from 18 goats (10 Boer and 8 Anglo-Nubian) were analyzed. A-kinase anchoring protein 4 localized to the acrosomal region. Low AKAP4 fluorescence intensity was linked to reduced total motility (45.3%; 95% CI, 41.1 to 49.5; partial η2 = 0.128), progressive motility (14.3%; 95% CI, 12.5 to 16.1; partial η2 = 0.131), and average path velocity, straight-line velocity, and beat cross frequency (partial η2 = 0.105 to 0.114), while curvilinear velocity showed a moderate effect (partial η2 = 0.060). The amplitude of lateral head displacement, straightness, linearity, wobble, plasma membrane, and acrosome integrity, viability, and reactive oxygen species were similar across groups (partial η2 = 0.002 to 0.042). Mitochondrial membrane potential was lower in the low group (52.3%; 95% CI, 48.0 to 56.6; partial η2 = 0.071) than in the medium group (62.2%; 95% CI, 58.3 to 66.1). No correlations were observed between AKAP4 and sperm parameters.
A-kinase anchoring protein 4 intensity in frozen-thawed goat sperm affects energy metabolism and motility in a nonlinear, threshold-dependent manner, serving as a categorical sperm quality indicator.
A-kinase anchoring protein 4 may serve as a biomarker for goat semen quality, particularly motility.