Criopreservación de espermatozoides del lenguado Paralichthys adspersus

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 < 0.05) were founded between the three different concentrations of dmso used. subsequently, we evaluated the effect of a non-permeable cryo-additive (chicken egg yolk, vhg), in order to obtain an increasing of the percentage of sperm motility. we used a 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 < 0.05). a high significant difference between the sperm motility percentages post-thawing using dmso and dmso with vhg, was observed.