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Study of the toxic effects of flame retardant PBDE-47 on the clam Chamelea gallina (Linnaeus, 1758)
Salvatora Angela Angioni,Giampiero Scortichini,Gianfranco Diletti,Fabrizia Perletta
Veterinaria Italiana , 2013,
Abstract: The purpose of the study is to evaluate the effects of 2,2',4,4'-tetrabromodiphenylether (PBDE-47) on the Chamelea gallina clam (according to current commercial regulations: Venus gallina). PBDEs, which are used as flame retardants in various industrial products, are classed as hazardous substances by Directive 2011/65/EU. They are bioaccumulative compounds, considered to be endocrine disruptors, genotoxic, neurotoxic and practically ubiquitous, and their concentration in the environment has considerably increased in recent years. The aim of this study is to establish the effects of PBDE-47 on Chamelea gallina: toxic power and any harmful effects on the gonads, bioaccumulation capacity in the tissues, and possible entry into the food chain. The research used 96-hour and 21-day experimental tests on clams housed in filtered seawater. The tests were preceded by a period of acclimatisation of the molluscs lasting five to seven days. The clams were fed on seaweed (Dunaliella tertiolecta). The choice of the toxic compound PBDE-47 was based on the high concentration, among the congeners of PBDE, found in some aquatic species. The study demonstrated that the concentration of the contaminant used did not alter the vital functions, cause significant levels of mortality or lead to evident alteration in the gonads of Chamelea gallina. However, the research demonstrated the bioaccumulation capacity of the bivalve mollusc, allowing PBDE-47 to enter the food chain.
Iris Dup?i?,Ana Brato?
Ribarstvo : Croatian Journal of Fisheries , 2004,
Abstract: Chamelea gallina clam is among 16 shellfish species commonly present on Croatian fish markets. In the year 2000, European fishermen collected 39,819 tons of this species. The most abundant settlements of Chamelea gallina are situated along western Adriatic coast, however, there are settlements along eastern Adriatic coast especially in the estuaries of Neretva and Cetina, Nin and Novigradsko more areas, as well as along the coasts of islands; Bra , Rab and Susak. Ecological parameters affect growth rates, reproduction and mortality. Due to great temperature oscillations insufficient spat recruitment occurs on occasion. Temperature values determine the time and the intensity of spawning. Hatcheries insure constant and secure spat resource. Adults from brood stock mature during conditioning process, after which they are transferred into spawning tanks for fertilization. Brood stock, larvae, and spat are fed by cultured phytoplankton species.
The clam (Chamelea gallina): evaluation of the effects of solids suspended in seawater on bivalve molluscs
Salvatora Angela Angioni,Carla Giansante,Nicola Ferri
Veterinaria Italiana , 2010,
Abstract: The study was designed to evaluate the effects of solids in suspension in seawater on clams (Chamelea gallina). The aim was to investigate the possible correlation between the widespread deaths of clams in the coastal waters of the central and northern Adriatic in the last five years and increased concentrations of solids in suspension. The research involved conducting 96-hour tests on clams farmed in aquariums containing filtered seawater. The tests were preceded by a 7-day adaptation stage to allow the molluscs to acclimatise. During this period, the clams were fed on unicellular seaweed (Dunaliella tertiolecta). The molluscs were exposed to particles of solids in suspension consisting of pools of silica gel (SiO2) granules of various sizes, similar to those constituting silt, whose presence and suspension in the sea considerably increase after heavy rain and heavy seas. The study established that the number of deaths caused by solids suspended in seawater at the concentrations used in the tests was not statistically significant.
Cytotoxic activity by the mussel Mytilus galloprovincialis and the Venus clam Chamelea gallina in the Adriatic sea in 2007
D Malagoli,L Casarini,F Fiori,E Ottaviani
Invertebrate Survival Journal , 2008,
Abstract: Given the ecological and economic importance of bivalve molluscs, the evaluation of their welfare is one of the primary aims for both biologists and people working in shell fishing. After a three year-long period monitoring the cytotoxic activity exerted by the hemolymph from the mussel Mytilus galloprovincialis, we have concluded that cytotoxicity represents a useful parameter to evaluate the status of the immune activity and therefore the health of mussels in a specific period of the year. During 2007, we compared the mussel cytoxicity with that of the Venus clam Chamelea gallina from contiguous areas of the Northern Adriatic Sea. Our observations indicate that the cytotoxicity of the hemolymph of the two species follows a similar course during the year, suggesting that cytotoxic activity is primarily determined by the life/reproductive cycles.
Investigations on the Stocks of the Striped Venus (Chamelea gallina L., 1758) in Ordu`s Coastal Zone of the Eastern Black Sea
Goktu Dalgic,Sedat Karayucel
Journal of Fisheries International , 2012,
Abstract: In this study population structure of striped venus (Chamelea gallina L., 1758) was investigated between Ak ay and Gülyal at the depth of 5-15 m in Ordu`s coastal zone of the Eastern Black Sea in December 2002 and June 2003. Totally 87 operations were conducted with a boat equipped with hydraulic dredge used for commercial clam fishing and sub samples were taken to collect data after each operation. Length-weight distributions and meat yield of 1332 individuals of C. gallina belonging to the stock at the site from Ak ay to Cape ünye were calculated. Mean meat yield was found to be 8.04 %. Total weight distributions were between 0.09 g and 5.7 g, while shell lengths were between 6.4 mm and 30 mm. Most of the clam shells were empty and only a few clams were live in all sites, except some parts of the site from Ak ay to Cape ünye. Present attitude was discussed according to the results.
Reproduction Cycle of Striped Venus Chamelea gallina from the Black Sea Coast of Turkey
Goktug Dalgic,Sedat Karayucel,Ibrahim Okumus
Journal of Animal and Veterinary Advances , 2012,
Abstract: The gametogenetic cycle of striped venus Chamelea gallina of southern Black Sea population was studied using standard histological technique and a condition index. There was a synchronism between sexes in terms of gametogenetic development. The beginning phase occurs during spring (March-May) and maturation occurs during Summer (June). Most of the spacemen spawn in July. The gonadal stages were consisted of five phases including primordial, development, mature, spawn and resting. Results obtained in this study fit with seasonal restrictions of C. gallina fishery in the Black Sea.
Studio degli effetti tossici del ritardante di fiamma PBDE-47 su vongola Chamelea gallina (Linnaeus, 1758)
Salvatora Angela Angioni,Giampiero Scortichini,Gianfranco Diletti,Fabrizia Perletta
Veterinaria Italiana , 2013,
Abstract: Lo studio ha avuto l'obiettivo di valutare gli effetti del 2,2',4,4'-tetrabromodifeniletere (PBDE 47) su vongola Chamelea gallina (Venus gallina secondo la normativa commerciale vigente). I PBDE, impiegati in diversi prodotti industriali come ritardanti di fiamma, sono annoverati tra le sostanze pericolose dalla Direttiva 2011/65/UE. Si tratta di composti bioaccumulabili, ritenuti interferenti endocrini, genotossici e neurotossici, praticamente ubiquitari, la cui concentrazione nell'ambiente, negli ultimi anni, è aumentata in maniera considerevole. Il presente studio ha avuto l'obiettivo di verificare gli effetti del PBDE-47 su Chamelea gallina: potere tossico ed eventuali effetti dannosi sulle gonadi, capacità di bioaccumulo nei tessuti e possibile ingresso nella catena trofica. La ricerca si è avvalsa di prove sperimentali a 96 h e a 14-21gg su esemplari di vongola stabulati in acqua marina filtrata. Le prove sono state precedute da un periodo di adattamento dei molluschi della durata di 5-7gg. Le vongole sono state alimentate con alghe marine (Dunaliella tertiolecta). La scelta del composto tossico PBDE-47 è stata effettuata in considerazione delle maggiori concentrazioni, tra i congeneri di PBDE, riscontrate in alcune specie acquatiche. Lo studio ha evidenziato che le concentrazioni impiegate del contaminante non hanno alterato le funzioni vitali, causato livelli significativi di mortalità e determinato alterazioni evidenti alle gonadi di Chamelea gallina. La ricerca ha evidenziato, comunque, il potere di bioaccumulo del mollusco bivalve, permettendo al PBDE-47 l'ingresso nella catena trofica.
Detection of Vibrio splendidus and related species in Chamelea gallina sampled in the Adriatic along the Abruzzi coastline
Marina Torresi,Vicdalia A. Acciari,Annamaria Piano,Patrizia Serratore
Veterinaria Italiana , 2011,
Abstract: Vibrio species are an important and widespread component of marine microbial communities. Some Vibrio strains are potentially pathogenic to marine vertebrates and invertebrates. The aim of this study was to identify vibrios, in particular Vibrio splendidus and related species, isolated from clams (Chamelea gallina) collected along the coasts of the Abruzzi region from May to October 2007. The isolates obtained were phenotyped and classified as belonging to the genus Vibrio. The strains underwent biochemical testing in accordance with Alsina’s scheme for V. splendidus identification. Molecular analysis of the 16S-23S intergenic space region and recA gene was used to identify V. splendidus and related species. All the samples examined were found to contain halophylic Vibrio species, with V. alginolyticus, V. splendidus-related species and V. mediterranei most commonly found. A polymerase chain reaction of the 16S-23S intergenic space region and sequencing of the recA gene from isolates confirmed that phenotyping of Vibrio species is not sufficient to distinguish between different species. Differentiation of the highly related species among V. splendidus-related clusters remains an important issue. In this regard, our data suggests sequencing the recA genes was far more discriminatory than sequencing 16S rDNA for this purpose.
Sequencing and Characterization of Striped Venus Transcriptome Expand Resources for Clam Fishery Genetics  [PDF]
Alessandro Coppe, Stefania Bortoluzzi, Giulia Murari, Ilaria Anna Maria Marino, Lorenzo Zane, Chiara Papetti
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0044185
Abstract: Background The striped venus Chamelea gallina clam fishery is among the oldest and the largest in the Mediterranean Sea, particularly in the inshore waters of northern Adriatic Sea. The high fishing pressure has lead to a strong stock abundance decline, enhanced by several irregular mortality events. The nearly complete lack of molecular characterization limits the available genetic resources for C. gallina. We achieved the first transcriptome of this species with the aim of identifying an informative set of expressed genes, potential markers to assess genetic structure of natural populations and molecular resources for pathogenic contamination detection. Methodology/Principal Findings The 454-pyrosequencing of a normalized cDNA library of a pool C. gallina adult individuals yielded 298,494 raw reads. Different steps of reads assembly and filtering produced 36,422 contigs of high quality, one half of which (18,196) were annotated by similarity. A total of 111 microsatellites and 20,377 putative SNPs were identified. A panel of 13 polymorphic transcript-linked microsatellites was developed and their variability assessed in 12 individuals. Remarkably, a scan to search for contamination sequences of infectious origin indicated the presence of several Vibrionales species reported to be among the most frequent clam pathogen's species. Results reported in this study were included in a dedicated database available at http://compgen.bio.unipd.it/chameleabase. Conclusions/Significance This study represents the first attempt to sequence and de novo annotate the transcriptome of the clam C. gallina. The availability of this transcriptome opens new perspectives in the study of biochemical and physiological role of gene products and their responses to large and small-scale environmental stress in C. gallina, with high throughput experiments such as custom microarray or targeted re-sequencing. Molecular markers, such as the already optimized EST-linked microsatellites and the discovered SNPs will be useful to estimate effects of demographic processes and to detect minute levels of population structuring.
Vongola (Chamelea gallina): valutazione degli effetti dei solidi sospesi in acqua marina nel mollusco bivalve
Salvatora Angela Angioni,Carla Giansante,Nicola Ferri
Veterinaria Italiana , 2010,
Abstract: Lo studio è finalizzato alla valutazione degli effetti dei solidi sospesi in acqua marina nella vongola (Chamelea gallina). L’obiettivo è quello di verificare la possibile correlazione tra le morie di vongole, registrate negli ultimi 5 anni, nelle acque costiere del Mare Adriatico centro-settentrionale e l’aumento della concentrazione dei solidi sospesi. La ricerca è stata effettuata mediante l’implementazione di prove sperimentali a 96 h su esemplari divongola, stabulati in acquari contenenti acqua marina filtrata. Le prove sono state precedute da una fase di adattamento dei molluschi bivalvi della durata di 7 giorni. In questo periodo le vongole sono state alimentate con alga unicellulare marina (Dunaliella tertiolecta). I molluschi sono stati esposti a particelle di solidi sospesi costituite da pool di granuli, di varie dimensioni, di silica gel (SiO2) simili a quelli costituenti il limo, la cui presenza e sospensione in mare aumentano notevolmente in seguito ad abbondanti piogge e forti mareggiate. Lo studio ha verificato come le concentrazioni utilizzate dei solidi sospesi in acqua marina, impiegata nelle prove, abbia provocato un numero di esemplari morti, statisticamente, non significativo.
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