Optimization of short-term storage of pikeperch semen: an applicable approach

Abstract

Contamination of semen with urine and asynchronous maturation of males and females are main obstacles in artificial reproduction of pikeperch Sander lucioperca. The objective of this study was to overcome these obstacles using optimization of a procedure for short-term storage of pikeperch semen at 4°C using two immobilizing media (IM): (a) IM1, 180mM NaCl, 2.68mM KCl, 1.36mM CaCl2⋅2H2O and 2.38mM NaHCO3, 343mOsm/kg; and (b) IM2, 200mM NaCl, 2.68mM KCl, 1.36mM CaCl2⋅2H2O and 2.38mM NaHCO3, 381mOsm/kg. Undiluted sperm was used as the control. At 6h poststorage, there were no substantial changes in spermatozoa motility and velocity at 30s postactivation in all groups. Over 48h of storage, the highest spermatozoa motility and velocity were obtained in sperm diluted in IM2 compared to the other groups. IM2 could maintain a significantly higher ATP content of diluted sperm than IM1 and undiluted treatment for 2days. Similarly, the highest values of eyeing and hatching rates were observed in sperm diluted in IM2 compared to sperm in the other studied groups. It can be concluded that the obtained result is a novel and applicable approach to maintain semen quality of pikeperch during short-term storage, suggesting IM2 as a promising medium for short-term storage. The present study also opens possibilities for ensuring a reliable source of semen as a convenient approach for increasing genetic diversity in hatcheries.