How do taurine and ergothioneine additives improve the parameters of high- and low-quality turkey semen during liquid preservation?

Abstract

Abstract The study aimed to examine the parameters of turkey ejaculates (n=40) of high and low quality (HQ and LQ, respectively), preserved with the addition of taurine (TAU; 5 mM, 10 mM) and ergothioneine (EGT; 5 mM, 10 mM) for 48 h at 5°C in a liquid state. The motility, plasma membrane integrity (PMI), mitochondrial function, apoptotic and necrotic spermatozoa percentage, and sperm cells that generated NO were determined after 2, 24, and 48 h of storage. The preserved semen was also analysed for the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione (GSH) content, and malondialdehyde (MDA) production. Taurine, in both doses, may improve the antioxidant status of stored turkey semen as well as sperm motility, viability and functionality regardless of ejaculate quality, as manifested by increased SOD and CAT activities, reduced MDA levels, and enhanced sperm characteristics i.e. plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), total motility (TMOT), and progressive motility (PMOT). In turn, the addition of EGT increased GSH content in the external environment and suppressed lipid peroxidation in turkey spermatozoa, in particular those from low-quality (LQ) ejaculates. However, it appears that EGT could deliver more satisfactory results when added at lower concentrations.