Some properties of bream Abramis brama L-sperm and its cryopreservation

Concentration and motility of spermatozoa, total protein content and its el ectrophoretic profile, glucose content, activity of aspartate aminotransfer ase (AspAT) and acid phosphatase (AcP) were assessed in 18 samples of semen from common bream Abramis brama L. males, which were hormonally stimulated to spermiation. Also, milt pooled from four donors was cryopreserved as pe llets in vapours of liquid nitrogen (-80 degrees C) using four extenders (e ach with or without the addition of hen egg yolk). Mean spermatozoa concent ration was 11.68 x 10(9) mL(-1), and mean spermatozoa motility was about 60 %. Protein content in seminal plasma was 2.08 mg mL(-1); both PAGE and SDS- PAGE showed considerable heterogeneity of protein fractions. Mean glucose c ontent was over 11 mg%. AspAT and AcP activities were detected in both semi nal plasma and spermatozoa extracts. As calculated to 1 x 10(9) spermatozoa , AcP and AspAT activities were almost sixfold and 46-fold higher in sperma tozoa than in seminal plasma respectively. In the best variant, cryopreserv ation attempts resulted in 66.6% of eyed embryos (compared with control fer tilization) obtained after fertilization of eggs with cryopreserved semen.