Gamete cryopreservation is a biotechnology that can guarantee a continuous supply of gametes, regardless of the seasonal reproductive cycle. In this study we developed a protocol for the cryopreservation of the sea urchin Paracentrotus lividus spermatozoa, with a view to the creation of cryobanks of semen to be used as a model system in laboratory research and ecotoxicological tests. All the key phases of the procedure were separately considered and the effect on sperm motility was evaluated by means of computer assisted analysis. The best results were obtained using 7% dimethylsulfoxide in 1% NaCl plus 0.04. M trehalose as the extender, at a freezing rate of -20. °C/min. On thawing, in semen samples cryopreserved in accordance with this protocol the velocity parameters of the sub-population of rapid sperm (best performing spermatozoa) did not significantly differ from semen on collection; in addition also the fertilization ability was restored, and about 50% of normal developed plutei larvae were obtained by thawed semen. The developed protocol is rapid and easy-to-perform; moreover, the use of gametes from reared urchins makes it unnecessary to continuously collect specimens from natural populations, making this procedure a promising starting point for the creation of alternative and more sustainable methodologies in laboratory research on sea urchin gametes and embryos. © 2014 Elsevier Inc.

The seasonal variability of physico-chemical and biological parameters was observed from October 2012 to October 2013 inside and outside a farming area in the Southern Adriatic sea (Italy), to assess the impact of the mussel farming on ecology and biology of the area. Temperature showed a typical seasonal trend from 7°C to 27°C, while the salinity range was 34-39 psu. Oxygen saturation was close to 100% at the surface layers and decreased up to 60% near the bottom during the spring, suggesting its consumption by organic matter mineralization processes, which affected ammonia and phosphorous, with the highest concentrations measured outside area (4.73 ?M and 2.12 ?M, respectively). Increased values of oxidative nitrogen in winter (12.01 ± 3.67 ?M) were highlighted. A typical seasonal trend was observed for silicates from 5.59 ± 2.36 ?M in winter to 0.45 ± 0.28 ?M in spring. Chlorophyll a values reflected mixing and upwelling processes, with a peak of 6.70 ?g.l-1 in March, characteristic of the maximum phytoplankton production (1.53 x 106 cell.l-1). Diatoms represented the predominant taxonomic group (52%) in abundance and number of species for all the period, suggesting constant eutrophic conditions in both sites. The temporal trend of diatoms is roughly similar for both the sites, except for the spring-summer period, when a decrease of 50% of diatoms abundance was observed outside and a greater deviation of 80% was found inside the farming area.

Specimens of Engraulis encrasicolus (Osteichthyes: Clupeiformes) (Linnaeus, 1758) werecollected monthly from the Adriatic purse seine fishery from June to December 2013 in order to studythe reproductive traits and the condition of the population. Temporal trend of gonadosomatic index andmacroscopic examination of the maturity stages of gonads show that the temporal changes in anchovycondition appear to be related to the sexual cycle. Furthermore, anchovy seems not separate feeding andreproduction over the time.

Specimens of Engraulis encrasicolus (Osteichthyes: Clupeiformes) (Linnaeus 1758) werecollected monthly from the Adriatic purse seine fishery from June to December 2013 in order to study thereproductive traits and the condition of the population. Temporal trend of gonadosomatic index andmacroscopic examination of the maturity stages of gonads show that the temporal changes in anchovycondition appear to be related to the sexual cycle. Furthermore, anchovy seems not separate feeding andreproduction over the time.

The evaluation of the motility parameters, assessed by computer-assisted analysis, after 5-year storage in liquid nitrogen is sea bream cryopreserved spermatozoa was made, in comparison with those recorded on fresh semen and on semen thawed after freezing.

The aim of this study was to evaluate, by computer-assisted analysis, the motility parameters of cryopreserved sea bream spermatozoa after prolonged storage (up to 5 years) in liquidnitrogen in comparison to the performances of fresh semen and of semen thawed 1 month after freezing (cryopreservation medium: 1% NaCl containing 5% DMSO; freezing rate: 10°C min
1; stored in liquid nitrogen). Semen samples were thawed 1 month and 5 years after cryopreservation. Sperm motility was analyzed by means of the Sperm Class Analyzer
(SCA, Microptic, Barcelona, Spain). The percentages of motile sperm and rapid sperm curvilinear velocity >100 lm s
1 only), and the curvilinear, straight-line and average path velocities (lm s
1) were evaluated. The percentages of total motile and rapid sperm, as well the relative velocity levels, were slightlylower in thawed semen than in fresh semen (for example, 85 vs 95% for total motile sperm; 70 vs 80% for rapid sperm; 200 vs 300 lm s
1 for VCLt; 250 vs 350 lm s
1 for VCLr). Data of all trials did not differ in relation to storage time. It can therefore be concluded that long-term storage of large amountsof cryopreserved semen was homogeneous, providing high quality sea bream semen for use in fertilization trials in both aquaculture and laboratory research.