Comparison of two different methods in the cryopreservation of Eurasian perch (Perca fluviatilis) sperm

Abstract

Two different cryopreservation methods were compared and an optimal dilution ratio for the use of controlled-rate freezer (CRF) was established for Eurasian perch (Perca fluviatilis) sperm. Progressive motility (72±15%) and curvilinear velocity (VCL, 146±11μm/s) of sperm cryopreserved with CRF did not reduce significantly compared to fresh sperm [progressive motility (90±4%), VCL (173±24μm/s)]. On the other hand, progressive motility (62±15%) and VCL (120±21μm/s) of sperm cryopreserved with the conventional floating frame technique were significantly lower when compared to the fresh control. Sperm in both cryopreserved groups showed significantly higher straightness [STR, CRF (84±4%), frame (84±2%)] than in the fresh control group (68±4%). Perch sperm cryopreserved with CRF at a dilution ratio of 1:20 showed significantly higher progressive motility (49±6%) than at a ratio of 1:5 (39±6%) and showed significantly higher VCL (129±11μm/s) than at dilution ratios of 1:10 (112±17μm/s) and 1:5 (115±9μm/s).