Cryopreservation of flounder Paralichthys adspersus spermatozoa

Abstract

To optimize the techniques of captive breeding of flounder Paralichthys adspersus, a methodology was developed for the cryopreservation of spermatozoa of this species. The effect on sperm motility post-thawing, using three different concentrations (1.0; 1.5 and 2.0 M) of DMSO as cryoprotective agent and five different freezing rates -7.5; -10; -12.5; -20 and -30°C min-1, with an automatic programmable freezer was evaluated. The highest percentages of post-thawing sperm motility were obtained by freezing sperm at -10°C min-1, no significant differences (P cryoprotectant solution including DMSO at three different concentrations adding 10% VHG v/v. The highest percentages of sperm motility (71.71 ± 13%) were obtained at the freezing rate of -10°C min-1 without significant differences between the three concentrations of the cryoprotectant solution in which the sample was incubated sperm (P