Sperm Cryopreservation of Red Seabream Pagrus major

Abstract

The aim of this study was to determinate the optimal conditions in sperm cryopreservation in red seabrem Pagrus major. Two extenders and five cryoprotectants (CPAs) in four different concentrations (5, 10, 15 and 20%) were evaluated on fresh sperm motility and post-thaw sperm motility. The sperm viability on fresh sperm was estimated immediately after dilution with the CPAs. Glycerol with glucose as extender showed the highest viability comparing with the other CPAs with a viability of 16.8 ±0.6 min showing no different between concentrations, and in post-thaw using glycerol as a CPA and sucrose as an extender, showed the highest values in spermatozoa activity index, duration of progressive motility, total duration of motility and survival rate. In 5, 10 and 15% gave a spermatozoa activity index of 4.0±0.0 the duration of progresive motilities were 9.8±0.7 min in 5%, 7.9±0.5 min in 10% and 5.7±3.3 min in 15%, respectively. With a total duration motility of 21.7±0.4 min in 5%, 16.1±2.3 min in 10% and 12.2±1.1 min in 15%,. and a survival rate of 82.0±1.7 % in 5%, 74.3±3.5 % in 10% and 60.0±3.6%. in 15% There was no significant difference in sperm viability between all the CPAs except sperm cryopreserved with methanol in all four concentrations. Methanol in all four concentrations turn up to be toxic for red seabream sperm. In conclucion, these methods of cryo-preservation of red seambream sperm are suitable for routine aquaculture application and preservation of genetic resource.