Effect of ß-glucan from Euglena gracilis as an antioxidant on goat semen cryopreservation

This study aimed to determine the influence of different doses of β-glucan on post-thaw spermatological parameters, lipid peroxidation, and total antioxidant activity of buck semen. In the non-breeding season, semen was collected from bucks twice weekly. After then, ejaculates were pooled and divided into four equal aliquots: β-glucan concentrations of 1 mM (βG1), 2 mM (βG2), and 4 mM (βG4), and a control group without antioxidants. Each sample group was diluted for cryopreservation using a dilution method involving two steps. The experimental groups were then evaluated for several parameters including sperm motility, plasma membrane functional integrity [hypoosmotic swelling test (HOST)], damaged acrosome rate [FITC-Pisum sativum agglutinin (FITC-PSA)], DNA integrity [terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)], mitochondrial membrane potential using JC-1, evaluation of lipid peroxidation, and determination of total antioxidant activity. The post-thaw motility and plasma functional integrity of the control group were significantly lower than those values in the βG groups (P < 0.05). Although the numerically greatest acrosome damage was detected in the control group, it was only statistically different from βG1 and βG4 (P