Effect of glutathione on viability and acrosomal integrity of bovine spermatozoa during graded cryopreservation

The present study was aimed to evaluate the effect of Glutathione, an anti-oxidant, on the acrosomal integrity bovine spermatozoa by means of Trypan Blue-Neutral Red- Giemsa Staining at different stages of semen preservation (after dilution, pre-freeze) and post thaw. The semen was primarly examined for standard samples. Samples (N=24) of more than 70% progressively motile spermatozo with concentration of \u003e600 million spermatozoa/ml was used for cryopreservation. The extension of fresh semen was done in a Glycerolated Egg Yolk Tris (GEYT) Extender upto 80 million sperm /ml. The various concentrations of Glutathione were added in diluted semen like 0.0 mM (Control), 0.5 mM (T1) \u0026 1.0 mM (T2). The semen was cryopreserved in French Mini Straw using liquid nitrogen vapour as per standard protocol for patticular time interval (lowering of temperature from 4°C to −10°C @ 5°C/min, −10°C to −100°C @ 40°C/min, −100 to −140°C @ 20°C/min). The acrosomal membrane integrity of spermatozoa was evaluated after staining with Trypan Blue –Neutral red-Giemsa stain at given time and temperature ratio. The viability of spermatozoa with intact acrosome at post-thaw (370C for 45 sec) was significantly higher (P\u003c0.05) in the treatment groups (T1) \u0026 (T2) and it was 54.43±0.65, 67.58±0.44 \u0026 61.69±0.55 in control, T1 (0.5 mM Glutathione) and T2 (1.0 mM Glutathione) groups respectively. Furtherly, with in two treatments a significant difference was aslo seen (P\u003c0.05) and it was higher in treatment group 1 (T1). Comparison (unpaired‘t’ test) between the bulls for control and treatment groups did not revealed any significant difference.