Triploidization in pikeperch (Sander lucioperca) induced by cold shock

Abstract

The present research investigated induction of triploidy using a cold temperature shock in pikeperch, Sander lucioperca L. In this study, a cold shock treatment by immersing eggs in an ice-water bath (1.0–1.1 °C) at 5, 7, 10, 15, and 20 min post-activation at fertilization (PA) for 20, 40, 60, 90, and 120 min was applied. Three out of 25 tested combinations of initiation time and shock duration resulted in 100% triploidy: initiation at 5 min PA for 90 and 120 min and at 7 min PA for 120 min. Shock treatments initiated at 20 min PA resulted in all- diploid larvae. The control treatment showed hatching rate of 66.2%, without any triploid production and 2.7% malformed larvae. Cold shock initiated at 5 min PA for 120 min resulting in 100% triploidy and a hatching rate of 20.2%, malformed larvae accounted for 5.5% of larvae was considered as the most effective treatment for inducing 100% triploidy in pikeperch.