Sperm quality of brazilian flounder paralichthys orbignyanus throughout the reproductive season

Abstract

The aimof this study was to evaluate the sperm quality of Brazilian £ounder Paralichthys orbignyanus throughout its reproductive season. Sperm was collected at the beginning, middle and end of the breeding period. Spermatozoa densitywasmaximumat the beginning (12.7 0.92 109 cellsmL 1) and at the end (11.8 0.39 109 cellsmL 1) of the breeding season (Po0.05). Sperm production and the percentage of spermatozoa moving fast forward increased signi¢cantly towards the end of the breeding season (Po0.05). The mean duration of progressive motility of spermatozoa was around 10min. No di¡erence was observed during the reproductive season in the percentage of motile cells, pH, osmolality and K1, Cl and Mg21 concentrations in seminal plasma. The concentration of Na1 increased throughout the breeding season, reaching 174.62 12.68mmol L 1 at the end (Po0.05). There was a decline in the concentration of Ca21 (12.31 3.08mmol L 1) in the middle of the breeding season, which coincided with the shortest motility duration of spermatozoa. The information reported in this study should help to improve management and optimize the development of protocols for short-termstorage and cryopreservation of Brazilian £ounder semen.