Redefining buck selection in the genomic era: linear appraisal breeding values as predictors of seminal quality

Abstract This study tested the hypothesis that predicted breeding values (PBVs) for linear appraisal and zoometric traits can serve as indirect genetic indicators of the potential to express specific seminal quality outcomes in Murciano-Granadina bucks. Records from 77 males and 1,901 ejaculates (2010–2019) were analyzed to evaluate the relationship between the genetic fraction of conformation traits and ejaculate parameters. Regularized canonical correlation analysis (RCCA) revealed strong multivariate associations, with the first canonical function explaining 52.6% of ejaculate volume, 82.0% of sperm concentration, 71.4% of progressive motility, 70.5% of Acrosome Integrity/Intact acrosomes, and over 60% of endosmosis and dose-related traits (canonical correlation r = 0.62, Wilks’ λ = 0.52, p < 0.01). PBVs for robustness-related traits, including chest width, rump width, and body depth, were indirect genetic indicators of potential for higher semen output and concentration, while PBVs for mobility and leg conformation reflected potential for reduced motility and lower ejaculate usability. Cross-validation confirmed the stability of these associations (optimal CV score = − 0.014). These findings support the hypothesis that PBVs capture meaningful genetic signals linked to seminal quality, providing a framework for incorporating reproductive potential into breeding strategies that balance productivity and fertility in Murciano-Granadina goats.