The algal polysaccharide agar has long been used as a food binder due to its structure, rheological behaviour, stability and interactions properties that help to generate ¢rm, round, disk-shaped pellets that may be used in recirculating sea urchin-rearing systems. Three algae-based diets (Ulva lactuca, Gracilaria gracilis, Cystoseira sp.) containing 3%and 6% agar were tested on the sea urchin Paracentrotus lividus in order to examine the e¡ect of varying percentages of agar on pellet stability in water and sea urchin gonad growth. The kinetics of water absorption and solute leaching of pellets were measured by immersing quadruplicate samples of the pellets inwater for1,2,3,4,5 and 6 days. Our resultsshow that the pellets had good water stability, were readily consumed by sea urchins and the presence of agar did not hamper sea urchin gonad growth. Animals fed Ulva-containing pellets reached a more advanced gametogenic stage with respect to animals fed Cystoseira- and Gracilaria-containing pellets. Moreover, the presence of agarase activity in the digestive system indicated that agar may be an energy source. Pellets are relatively low cost and easy to prepare and store. They may represent auseful resource for rearing sea urchins under intensive conditions.

Male gonads of Engraulis encrasicolus (Osteichthyes, Engraulidae) (Linnaeus, 1758) collected in the Lesina Lagoon from May to September 2012 were histologically examined in order to determine the maturity stage. All specimens were ripe with gonads to the spermatozoal stage. The small lengths of anchovies suggest that the male population in the Lesina Lagoon is composed of young individuals at their first maturity. The temporal evolution of the gonad morphology suggests that the reproductive activity peak was reached at the end of summer.

Coastal lagoons are highly connected to the sea and many fish species enter into these environmentsremaining there for short periods. The European anchovy, Engraulis encrasicolus (L.), is a speciesintensely exploited by fishing in the Adriatic Sea, and it occurs in the Lagoon of Lesina only during thespring-summer months, when it finds in the lagoon suitable environmental conditions that could enhancethe fitness of individuals. The purpose of this work was to characterize the European anchovy populationin the Lagoon of Lesina, by studying the reproductive biology and estimating the age, size and growthparameters of the specimens. The study also aimed at identifying any relationship between the growth andmaturity of anchovy and some environmental parameters. To achieve this goal, samples of Europeananchovy were collected about every fifteen days between May and September 2012, using fyke-nets. Atthe same time, water temperature, salinity, oxygen concentration and pH were measured with amultiparametric probe. In addition, water samples were collected for the chlorophyll a and suspendedparticulate matter measurements, and to describe phytoplankton assemblages of the lagoon. In thelaboratory, each specimen was measured and weighted; the otoliths were removed and stored dry inlabelled envelopes for age determination. The sex was determined and the fish gonads weremacroscopically classified. Moreover, gonad samples (at least 10 specimens for each sampling) werefixed in 4% buffered formalin for histological analysis. Water samples for photosynthetic pigments weresequentially filtered to separate three size classes: total, micro- and nano-phytoplankton forspectrofluorometric measurements. Water samples for total suspended solids were filtered and dried toestimate their concentrations. The phytoplankton cells were counted and identified by invertedmicroscope and the organisms were classified and grouped into three main taxonomic components:diatoms, dinoflagellates and others. The most significant results are illustrated.

The aim of this study was to test the sensitivity of computerized sperm motility analysis in the sea urchin Paracentrotus lividus as the endpoint in toxicity bioassays. The tested matrices were pore water samples collected in an agriculture-impacted Mediterranean lagoon, Lake Varano (Italy). Two standardized bioassays were also conducted as controls, the P. lividus spermiotoxicity test and the Vibrio fischeri (Microtoxs) test. VCL (curvilinear velocity), VSL (straight line velocity), VAP (average path velocity), and the percentage of rapid spermatozoa recorded by the Sperm Class Analyzers system showed high sensitivity and discrimination ability, to a degree comparable with the larval development endpoint of the spermiotoxicity test. The test evaluated in this study requires small volumes of matrices, involves minimal sample manipulation, and can easily be extended to many other bioindicator species. It may therefore be considered a promising ''quick response tool'' following hazardous events that may adversely affect an aquatic ecosystem.

The aim of this study was to evaluate the feasibility of using cryopreserved S. aurata semen in spermiotoxicity tests. Cryopreservation is a biotechnology that can provide viable gametes and embryos on demand, rather than only in the spawning season, thus overcoming a limitation that has hindered the use of some species in ecotoxicological bioassays. Firstly, the sperm motility pattern of cryopreserved semen was evaluated after thawing by means of both visual and computer-assisted analyses. Motility parameters in the cryopreserved semen 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 cadmium as the reference toxicant, in order to evaluate the sensitivity of cryopreserved S. aurata semen to ecotoxicological contamination. The sensitivity of the sperm motility parameters used as endpoints (motility percentages and velocities) proved to be comparable to what has been recorded for the fresh semen of other aquatic species (LOECs from 0.02 to 0.03 mg L-1). 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.

Italy) is a semi-enclosed and strongly polluted basin. For decades,it has been subjected to different anthropogenic impacts.These stressors caused severe sediments contaminationwith high concentration of different pollutants (PAHs, PCB,heavy metals). In order to assess the current status of sedimentscontamination, an ecotoxicological investigation combinedwith chemical analysis (heavy metals, PAH, and PCB)has been performed. In order to derive ecologically relevantconclusions, a multiorganisms and multiend-points approachhas been applied, exposing organisms from different trophiclevels to elutriate and whole sediment. The battery of bioassaysconsists of a microalgal growth inhibition test(Dunaliella tertiolecta), acute and sublethal assays (endpoints:mortality, immobilization and swimming speed alteration)on crustaceans larvae and juveniles, and rotifers(Amphibalanus amphitrite, Artemia salina, Corophiuminsidiosum and Brachionus plicatilis), and embryotoxicity teston echinoderms (Paracentrotus lividus). Considering the highlevels of sediment contamination highlighted from chemicalanalysis, an unexpected very low toxic effect was observed,even considering the sublethal end-point (larval swimmingspeed alteration). The results of this study suggest a very complexcontaminants dynamic in the Mar Piccolo sediments that,despite a strong level of contamination, seems to not affect in aproportional manner the biological compartment.

Silver nanoparticles (Ag-NPs) are increasingly used in a wide range of consumer products and such an extensive use raises questions about their safety and environmental toxicity. We investigated the potential toxicity of Ag-NPs in the marine ecosystem by analyzing the effects on several organisms belonging to different trophic levels. Algae (Dunaliella tertiolecta, Skeletonema costatum), cnidaria (Aurelia aurita jellyfish), crustaceans (Amphibalanus amphitrite and Artemia salina) and echinoderms (Paracentrotus lividus) were exposed to Ag-NPs and different end-points were evaluated: algal growth, ephyra jellyfish immobilization and frequency of pulsations, crustaceans mortality and swimming behavior, and sea urchin sperm motility. Results showed that all the end-points were able to underline a dose-dependent effect. Jellyfish were the most sensitive species, followed by barnacles, sea urchins, green algae, diatoms and brine shrimps. In conclusion, Ag-NPs exposure can influence different trophic levels within the marine ecosystem.

Paracentrotus lividus (Echinodermata: Echinoidea) adult specimens were reared in arecirculating aquarium under controlled conditions up to 4 weeks to evaluate the effect of the light andfeeding regime on gonad growth. Gonad yield and reproductive conditions were influenced by feedingregime, while light regime proved to have no effect on them.

Paracentrotus lividus (Echinodermata: Echinoidea) adult specimens were reared in a recirculating aquarium under controlled conditions up to 32 weeks to evaluate the effect of the prolonged rearing time on fertilization ability and on the sperm motility pattern. At the end of the trial all the evaluated parameters showed levels comparable to the field-matured specimens.

The results presented in this work are part of a pilot project aimed at the evaluation of the potential biodiesel production from algal biomass. Specifically, macroalgal and phytoplanktonic biomass of two Italian lagoon, Orbetello (north Tyrrhenian Sea) and Lesina (south Adriatic Sea), regarded as highly productive and eutrophic, were monitored in spring and summer 2011 and 2012. The study has been divided in two main sections. Firstly, a general qualitative outline of the submerged vegetation distribution by visual census techniques was conducted. Secondly, macroalgae and water samples for chlorophyll a determination were collected in order to study the primary production (in Kg.m-2 and ?g.L-1 for macroalgae and phytoplankton, respectively). Accordingly the lagoons have been divided into transects oriented according to the direction NS and WE. We obtained a total of 18 transects oriented in NW-SE direction in the Orbetello (8 in the western basin and 10 in the eastern basin) and 13 in the Lesina (10 of them in the "Sacca Orientale"). At the same time, physico-chemical parameters were measured by multiparametric probe. The results show a basic difference between the two systems, with a productivity shift towards phytoplankton biomass in Lesina and macroalgae in Orbetello. In Lesina, mean concentrations of chlorophyll a were 2.97 ± 3.63 ?g.L-1 (spring, with maximum of 15.27??g.L-1) and 2.36 ± 2.60 ?g.L-1 (summer, with peak of 12??g.L-1), while macroalgal biomass ranged from 1.9 to 2.6 kg.m-2 for both observation periods. Conversely, in Orbetello lagoon mean phytoplanktonic chlorophyll a did not exceed the level of 0.51 ±0.31 ?g.L-1 in spring and 0.81 ± 0.70 ?g.L-1 in summer (with maximum of 3.21 ?g.L-1), while biomass of submerged vegetation was always an order of magnitude greater. In particular, macroalgal biomass was higher in the western basin than in the Eastern one with mean values that increased from spring (28.2 Kg.m-2) to summer (66.1 kg.m-2). This study indicates that the high macroalgal production in Orbetello lagoon could be evaluated for biodiesel production, while in Lesina the macroalgae distribution is more casual e quantitatively less abundant.

The blue crab Callinectes sapidus (Rathbun, 1896), a native to western Atlantic coasts, is widely recorded in various Mediterranean regions,including the Gargano lagoons in the Adriatic Sea. This study investigated selected biological traits of Callinectes sapidus females in theLesina and Varano lagoons during their breeding migration to more saline waters. In total, 19 individuals of Callinectes sapidus, 15 femalesand four males, were collected in the lagoons near the mouths of the seaward channels. The specimens' Carapace Width ranged from 115 to230 mm, classifying them as medium to large crabs. In Varano lagoon in April and May 2014, two ovigerous females with egg masses of63.39 g and 11.65 g respectively were captured. This represents the first record of ovigerous females of C. sapidus in this lagoon. Theaverage Gonado-Somatic Index was 2.91±1.82 and 1.65 ± 0.65 for the specimens captured in Varano and Lesina lagoons, respectively. Theaverage Hepato-Somatic Index was 3.88±0.80 and 4.22±0.31 for specimens captured in Varano and Lesina, respectively. Egg diameterranged between 0.23 and 0.35 mm. Histological analysis of gonads showed stages from III to V, with individuals in emission or postissuancestages. This study presents evidence of the establishment of C. sapidus populations in Varano lagoon in the south-west Adriatic Seaand provides additional information on this species in the Lesina and Varano lagoons.

A 4-wk rearing trial of the sea urchin Paracentrotus lividus was carried out in a closed-circuit system in the presence and absence of food supply to evaluate the short-term response of gametogenesis to different feeding conditions. At the end of the trial, the gonad index (GI) was calculated, histological analyses of the gonads were performed, gamete fertilization ability was evaluated, and sperm motility was assessed by computerized motility analysis. Starvation significantly affected gametogenesis, whereas developing gametes were always observed in fed animals, whose GI had doubled by the end of the 4-wk trial. No differences were recorded between gametes from reared (fed) urchins and wild-collected ones. Although spent gonads frequently contained unspawned motile spermatozoa or morphologically intact eggs, the fertilization ability of gametes from starved urchins was significantly lower. It may be concluded that, although they were at the end of the reproductive season, the specimens fed ad libitum were able to reactivate the gamete maturation process immediately. This ability can be used in short-term procedures for roe enhancement and gamete production, particularly for specimens from areas in which environmental conditions determine slow gametogenesis and a consequently short reproductive season.

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.

Sea urchins of the species Paracentrotus lividus, collected along the Southern Adriatic coast at the end of their reproductive season, were reared in a recirculating aquarium under controlled temperature and feeding conditions in order to induce off-season maturation of gametes to be used in toxicity bioassays. After 14 weeks of rearing, the gonad index was calculated, histological analyses of the gonads were performed, their fertilisation ability was measured and the EC50 for copper in embryotoxicity bioassays was evaluated. The sperm motility pattern (based on the percentages of total motile and rapid sperm, together with sperm velocity parameters) was assessed using a computerised analyser. All specimens showed a significant increase in gonad yield with respect to field-collected animals and were in prespawning or spawning stages. The motility parameters, fertilisation ability and EC50 level of the collected gametes were comparable to those of field-matured specimens. In conclusion, the Sea urchins reared under experimental conditions were characterised by faster gonad maturation than the field population, producing viable gametes and larvae whose biological response in toxicity bioassayswas similar to that of field-reared specimens of P. lividus.

Bio-physical properties along a transect from coastal to offshore waters of the Southern AdriaticSea (Gulf of Manfredonia) were monitored during a multidisciplinary cruise in March 2012 and are herereported. Absence of stratification and presence of two systems with different bio-physical characteristicswere highlighted. Coastal waters resulted colder and less salty than off-shore waters. Primary biomassdata evidenced an increase of the values from the surface coastal waters to the depth of 25 m. A decrease ofphytoplankton biomass was also detected at the off-shore waters.

Hydrobiological properties along a transect from coastal to offshore waters of the Southern Adriatic Sea (Gulf of Manfredonia) were monitored during a multidisciplinary cruise in March 2012 and are here reported. Absence of stratification and presence of two systems with different hydrobiological characteristics are highlighted. Coastal waters resulted colder and less salty than off-Shore waters. Primary biomass data evidenced an increase of the values from the surface coastal waters to the 25 m layer. A decrease of phytoplankton biomass was also detected at the off-shore waters.

The histological evaluation of the gonads of Paracentrotus lividus (Echinodermata: Echinoidea) has been carried out from April to November on specimens sampled along the mid-to-low Adriatic coast. The % of individuals with gonads in active gametogenesis never decreased until 50% also in summer months, when a resting period would be expected. This continuous presence of individuals with an active gametogenesis is very useful in order to set up rearing protocols for a short-term induction of gonad yield and gamete maturation.

The aim of this study was to investigate the melatonin-mediated effects upon the neuroendocrine axis of the brackish killifish (Fundulus heteroclitus), a suitable experimental model to study reproductive events. The ability of melatonin to enhance reproductive capacity (fecundity, embryo survival and hatching rate) inducing the transcriptional activity of gonadotropin releasing hormone (gnrh), luteinizing hormone receptor (lhr) and melatonin receptor (mtnr) was investigated in adult females. Moreover, the melatonin-mediated enhancement of killifish sperm motility and velocity was found consistent with higher fecundity of melatonin-exposed fishes. As a further extent, Fourier Transform Infrared (FT-IR) microspectroscopy evidenced a reduction of lipid unsaturation level on isolated spermatozoa from treated males. Moreover, the reduction of mtnr gene expression during embryo development and lower biometric parameters documented in the larvae from melatonin-exposed parents suggest that melatonin acts as a hormonal mediator able to transfer the environmental signal to oocytes and then to embryos as inheritance of adaptive environmental changes. These results support the positive role of melatonin on killifish reproduction and its role as a maternal factor on embryo and larval development. © 2014 Elsevier Inc.

A new approach to environmental studies was investigated by the authors, who propose the use of cryopreserved biological systems in ecotoxicological bioassays. The feasibility of spermiotoxicity tests using cryopreserved semen of the sea bream Sparus aurata, with sperm motility parameters as the endpoint, was evaluated. Thawed sperm was incubated in environmental samples (sediment elutriate and dumpsite leachate) and in a reference toxicant (cadmium) at scaled concentrations. Motility was then evaluated by video-microscopy using both visual and computer-assisted analyses. Activation time, sperm motility and velocity and motility duration were assessed on thawing and at the end of the incubation time, and the difference with respect to the control was statistically evaluated. All the endpoints of the bioassay proved to have good sensitivity even at the highest dilutions of the tested matrices. Observed differences in the sensitivity thresholds of the endpoints were considered to be representative of different aspects of sperm physiology. Therefore the proposed bioassay is a promising starting point for the development of toxicity tests that are increasingly tailored to the needs of ecotoxicology and environmental quality evaluation strategies for aquatic environments.

In questo lavoro riportiamo alcuni recenti risultatiriguardanti la formulazione di pellet per l'alimentazionedi specie acquatiche, in particolare crostacei(gamberi) ed echinodermi (ricci di mare).L'aggiunta di polimeri di natura polisaccaridica,formanti una rete tridimensionale idrogel, consentedi realizzare pellet con una buona tenuta inacqua, resistenti e che mantengano le caratteristicheorganolettiche per un congruo periodo ditempo in accordo con il comportamento alimentaredelle specie allevate. L'aggiunta di molecolebioattive di svariata natura (es. derivanti da scartidel settore agroalimentare) consente inoltre diottenere pellet funzionali.

1 - The purpose of this study was to describe the basic characteristics of the European anchovy occurring in the Lagoon of Lesina in order to increase our knowledge of the ecology of the species in a lagoon ecosystem. 2 - Samples were collected between May and November 2012 using fyke nets. A hundred individuals per sample were measured and weighed. Sex was determined and the fish gonads were macroscopically classified. Length-frequency histograms were obtained, and the length-weight relationships and condition factors were estimated. 3 - The results of this study showed that the anchovies caught in the Lagoon of Lesina were relatively small. The growth of anchovies in the lagoon was often positively allometric (b>3) and exponent b was frequently greater than the value estimated for specimens in the Adriatic Sea in the same months. 4 - The sex ratio of anchovies in this study was skewed towards females in almost all the sampling period. Macroscopic analysis of the gonads revealed that spawning took place during spring-summer, and it prolonged until October in the females. One peak of ripe females and males was observed in June and one in August-September. 5 - This study suggests that the anchovy population in the Lagoon of Lesina is probably composed of a large number of young individuals at the first maturity. Individual growth seems to be positively affected by the environmental conditions of the lagoon, which probably provide the anchovies with a substantial trophic advantage. © 2013 University of Salento- SIBA.

Aphanius fasciatus (Valenciennes), Atherina boyeri Risso and Knipowitschia panizzae (Verga) are considered resident fish species in Italian coastal lagoons, which spend their entire life cycle within the brackish waters. They are short-lived species, with a small size, and a rapid growth and attainment of sexual maturity. All these fish species are included in the IUCN Red List with the status of Least Concern. A. fasciatus and K. panizzae are additionally listed in the Appendix III of the Bern Convention and in the Annex II of the European Union Habitat Directive.The aim of this study was to determine the population structures, to assess the length-weight relationships (LWRs) and to estimate the growth parameters of the target species in the lagoons of Lesina and Varano. This information is necessary for population assessments, which provide information that may be used in the management of fish populations in lagoon systems.Sampling of specimens was seasonally conducted in the two lagoons from May 2008 to February 2010. Fishes were caught at eleven stations by fyke nets with 6 mm mesh size at the end. In the laboratory, all specimens were identified to species, measured for total length and weighted. Sex was macroscopically determined.A total of 3,242 specimens of A. fasciatus, 1,664 specimens of A. boyeri and 1,060 specimens of K. panizzae were analyzed. The length frequency distribution, the LWR and the growth parameters were derived for each species in each lagoon. LWRs were estimated by linear regression analysis of the log-converted weight and total length data. Parameters of the von Bertalanffy growth function were determined through the ELEFAN-I software, using length frequency distribution. This study presents the first estimation for K. panizzae of LWRs and von Bertalanffy growth model parameters. Comparisons of the results were performed in relation to the lagoon environments and considering the knowledge about the species.

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.

This study analyses some aspects of Carcinus aestuarii biology within the project MOLEVAR funded byFEP ( European Funds for Fishing) in order to evaluate the crabs, Carcinus aestuarii, as a new economicresource for Varano Lagoon (S Italy). The population structure and reproductive biology of this specieswill be studed in three different sites of the lagoon. A total of 148 specimens were obtained from May toAugust 2012; 139 males and 9 females were observed. Length (CL) and width (CW) of the carapace andtotal weight (TW), were determined sex and development stage. At the same time, water temperature,salinity, oxygen concentration and pH were measured with a multiparametric probe. The reproductivebiology of C. aestuarii will be performed through the histological study of the reproductive cycle of thefemale and will be calculated the sex ratio.

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.

Male adult specimens of the grooved carpet shell Ruditapes decussatus (Linnaeus, 1758)were collected from the Porto Pozzo lagoon (central-western Mediterranean) in order to evaluate if theirsperm motility is affected by the wide salinity variations of this area. The sperm motility parametersassessed by computer assisted analysis showed no significant differences in relation to the tested salinityrange.

Cryopreservation is a valuable tool for aquacultureas it provides continuous seed production, regardlessof the spawning season of the brood stock. Theselection of a suitable cryoprotectant with low toxicityand high water solubility is important to avoidmembrane injuries and intracellular ice crystallization.This study has been aimed at the assessment ofthe toxic effects of two usually applied cryoprotectants,1-2 propylene glycol (PG) and methanol(MetOH), on spermatozoa of the of lion-paw scallopNodipecten nodosus, by evaluating the sperm motilityand the development of D larvae after fertilizationprocedure. Sperm was exposed at room temperature(22°C) for 10, 20 and 30 min to different concentrationranges of two cryoprotectants. Regardingthe sperm motility, PG5%, PG7%, MetOH4% andMetOH6% did not show differences compared tocontrol (semen incubated in seawater) (P < 0.05).The development of D larvae was not affected by theexposition to PG5%, MetOH 4% and MetOH 6%.These results indicate the potential use of both cryoprotectantsfor cryopreservation procedures.

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.

Spatial and temporal variability in zooplankton was studied at eight stations located in the Lesina Lagoon (South Adriatic Sea) Salinity, temperature, dissolved oxygen and chlorophyll a (in the lagoon)at these stations were also assessed. The zooplankton community was characterised by clear seasonal oscillations and mostly represented by copepods and their larvae. The dominant copepod species were Calanipeda aquaedulcis and Acartia tonsa, which exhibited spatial-temporal segregation in the lagoon. C. aquaedulcis copepodites seemed to be better adapted to oligotrophic and oligohaline conditions compared with the A. tonsa population. The invasive species A. tonsa has completely replaced the formerly abundant Acartia margalefi. A positive correlation was found between abundances, total species numbers and trophic state. An increasing abundance trend was shown from the lagoon towards the sea. The highest diversity indices were recorded at the two channel inlets, during high tide due to the absence of a clear dominance of one or more coastal species and the co-occurrence of species of lagoon and marine origin.