Cryodamages occur during sperm cryopreservation. Cryopreservation of fish sperm usually results in marked decrease in sperm quality, such as swelling or disruption of the plasma membrane, mi-tochondrial dysfunction, diminished sperm motility, impaired velocity, shorter motility period, denatura-tion, and release of some enzymes from spermatozoa. In this paper, damages in morphology, physiology, biochemistry and metabolism, and genetic integrity of fish semen after cryopreservation are discussed. New approaches in assessment of fish thawed sperm quality such as computer assisted sperm analysis, flow cytometic analysis combined with fluorescent probes and single cell gel electrophoresis are also briefly reviewed.
The current status and importance of preserving fish germplasm resources were described. The basic principle of cryobiology and its application potentials in preservation of aquatic germplasm resources were examined. The mechanism of cryodamage was discussed. The recent advances and major problems in finfish gamete and embryo cryopreservation were reviewed. The prospects for cryopreservation research in fish gametes and embryos were looked into. The important research directions in cryopreservation of aquatic organisms were proposed.