Effect of pH, osmolality and ion concentration on spermatozoa motility and composition parameters of sperm and seminal plasma in pikeperch (Sander lucioperca L.)

Determining the appropriate conditions for the activation/inhibition of gamete is crucial for successful fertilization and gamete handling. The aim of the current study was to determine the effect of sucrose, glucose, sodium chloride, potassium chloride, and pH on spermatozoa motility in pikeperch (Sander lucioperca L.). Six parameters characterizing spermatozoa motility was determined by computer-assisted sperm analysis (CASA). The percentage of motile spermatozoa dropped with increasing osmolality of the activating solution, whereas linearity and motility duration were slightly improved in the solution of osmolality (up to 100-200 mOsm kg(-1)). Velocity and other motility parameters were less affected by this factor. The appropriate enviroment for the activation of spermatozoa was water of pH 8. Small batches of pikeperch spermatozoa were motile in the solution that was isotonic to seminal plasma (300 mOsm kg(-1)); therefore, we recommend stripping of milt directly into the immobilizing solution. The immobilizing solution should have osmolality above 400 mOsm kg(-1).