Combination of fetuin and trehalose in presence of low glycerol has beneficial effects on freeze‐thawed ram spermatozoa

Background Freeze‐thawing process negatively affects ram spermatozoa in terms of sperm quality, DNA integrity and antioxidant defence system. Thus, antioxidant supplementation of spermatozoa during freeze‐thawing is suggested to improve sperm parameters. Objectives The aim of this study was to determine the effects of fetuin and trehalose added into ram semen extender on sperm parameters, antioxidant parameters, antioxidant‐related gene expressions and DNA integrity during the freeze‐thawing process, in low glycerol concentration. Methods Semen samples collected from six mature rams were pooled and splitted into equal aliquots and diluted with a tris‐based extender containing different concentrations of glycerol (G5; %5 and G3; %3), fetuin (F; 2.5, 5 and 15 mg/mL) and trehalose (60 mm) as eight groups (G5F0, G5F2.5, G5F5, G5F15, G3F0, G3F2.5, G3F5 and G3F15). Results G3F5 group resulted in the highest motility, mitochondrial activity and viability and the lowest DNA fragmentation and DNA damage (p