The effects of varying concentrations of glutathione and trehalose in improving microscopic and oxidative stress parameters in Turkey semen during liquid storage at 5 °C

Since turkey reproduction is mainly through artificial insemination, short-term preservation of turkey semen is one of the most important issues in turkey reproduction management. The present study investigates the effects of glutathione (GSH) and trehalose on lipid peroxidation degree and turkey semen quality while being stored at 5 °C for 72 h. To this end, semen samples were collected from 20 turkeys with a weekly frequency for 12 weeks. A glucose-based extender was used to dilute the pooled semen. It was divided into seven equal parts with varying levels of glutathione [0.5, 1 and 2 mM), trehalose [50, 75 and 100] and control [extender without antioxidant]. Subsequently, the divided semen samples were stored at 5 °C for 72 h. Several sperm parameters such as motility and motion parameters, plasma membrane integrity (PMI), plasma membrane functionality, DNA integrity, and oxidative parameters were assessed following storage for 0, 24, 48, and 72 h. The obtained results indicated an improvement in the plasma membrane functionality and DNA integrity, along with the percentages of PMI in GSH-2 mM group in comparison to the control group following storage at 5 °C for 72 h (P ≤ 0.05). It is also notable that the 2 and 1 mM concentrations of GSH increased the spermatozoa motility and motion parameters in comparison to the control group, respectively (P ≤ 0.05). The study results indicated that GSH-2, 1 mM and trehalose- 100 mM concentrations reduced lipid peroxidase levels and increased total antioxidant activity, catalase, superoxide dismutase, and glutathione peroxidase in comparison to the control group (P ≤ 0.05). Our study's data show that improvement of semen parameters and oxidative stress parameters of turkey semen can be improved by glutathione at 2 and 1 mM and trehalose at 75 mM while storing it 5 °C.