Effect of glutathione on sperm quality after short-term cryopreservation in seurukan fish Osteochilus vittatus (Cyprinidae).

The objective of this present study is to determine the optimum concentration for glutathione in the cryopreservation of seurukan fish (Osteochilus vittatus) spermatozoa. A completely randomized design (CRD) was used with 6 treatments and 3 replications. The Seurukan fish sperm was diluted in extender with a ratio of 1:20 (sperm: extender), then glutathione was added at a concentration of 0, 10, 20, 30, 40 and 50  mg L-1 . Next, the sperm thawed at 39-40 °C for 3 min and mixed with 100 eggs which were randomly selected. The success of the fertilized egg was observed 6 h after fertilization, while the hatching rate was examined 60 h after fertilization. The ANOVA test showed that the addition of glutathione significant affected the sperms motility, fertility and hatching rate of seurukan fish Osteochilus vittatus eggs (P < 0.05). By segregation the fresh sperm, a higher sperm motility rate was recorded with an addition of 30 mgL-1 of glutathione (63.00 ± 5.89), however, this value was not significantly different from using concentration of 10 and 20  mg L-1 . A higher fertilization rate was produced using glutathione concentration of 50  mg L-1 (51.33 ± 17.01); however, it was also not significantly different from the concentration of 20, 30 and 40 mgL-1 . In addition, a higher hatching rate was also recorded using glutathione concentration of 50 mg L-1 (40.33 ± 12.89), this value was not significantly different from using 40 mgL-1 glutathione. Hence, a conclusion was drawn that the optimum concentration of glutathione is 40 mg L-1 of diluent.