**6. Conclusions**

Cryopreservation, coupled with insemination and short term storage techniques, will lead to an improvement of gamete management of marine fish species. In particular, sperm cryopreservation is considered as a valuable technique for artificial reproduction and genetic improvement since it allows the selection and the storage of gametes of high quality.

However, although seawater fish spermatozoa of marine fish are more resistant than freshwater species to the dynamic changes in osmotic pressure that occur during the process of cryopreservation (Dzuba & Kopeika, 2002), the freezing-thawing procedure, apart from the experimental protocol used and from the fish species considered, determines: a changes of the kinematic characteristics, damages to proteins and DNA, lipid modification and change of the phosphorylation state of proteins involved in sperm motility initiation. The knowledge of the effects of freezing–thawing procedure on spermatozoa is very important to improve cryopreservation techniques for semen of marine fish for the establishment of sperm cryobanks that could play a crucial role in the genetic management and conservation of aquatic resources.
