Exploration Project PE060: Ecotoxicological tests using fresh and cryopreserved semen of Sparus aurata for the monitoring of marine ecosystems

Programme: Deliberazione della Giunta Regionale del 6 agosto 2005, n. 1170 - Accordo di Programma Quadro in materia di “Ricerca Scientifica” nella Regione Puglia. Bando di evidenza pubblica, in materia di Progetti Esplorativi di Sperimentazione
Project Title: Ecotoxicological tests using fresh and cryopreserved semen of Sparus aurata for the monitoring of marine ecosystems
Summary: Aim of the project has been the set up of and ecotoxicological test using as biological system cryopreserved semen of the sea bream Sparus aurata. In the first phase of the research the sperm motility pattern of the sea bream semen has been characterized, by means of computer assisted sperm motility analysis. The sperm motility pattern has been therefore used as evaluation parameter for the optimization of the protocols for the semen management and cryopreservation, in order to create, together with the Ittica Caldoli Fish Farm, a cryopreserved semen stock of high quality and homogeneity, to be used in the next research phases. In the sea bream semen cryopreserved according to our protocol, motility parameters did not change significantly in the first hour after thawing, meaning that they were maintained for long enough to enable their use in spermiotoxicity tests. In the second phase of the research, bioassays were performed, using both reference toxicants (heavy metals, pesticides, PAH) and environmental matrices (sediment elutriates, dumpsite leachates), in order to evaluate the relative sensitivity of the cryopreserved S. aurata semen. Briefly, the innovative test set up during this research project can be summarized as follows: 1) semen thawing; 2) sperm motility pattern assessment; 3) incubation in the tested matrices; 4) post-incubation assessment of the sperm motility pattern; 5) effect percentages evaluation for each of the tested motility parameter. The test showed good reliability and was found to be rapid and easy to perform, requiring only a small volume of the sample. Moreover, cryopreserved semen is easy to store and transfer and makes it possible to perform bioassays in different sites or at different times with the same batch of semen. The proposed bioassay is therefore a promising starting point for the development of toxicity tests that are increasingly tailored to the needs of ecotoxicology and environmental quality evaluation strategies.