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Marine aquaculture releases mollusc shell debris which can accumulate on the seabed. Due to its low degradability, mollusc shell debris becomes integrated into the sediment, modifying both its structure and associated biogeochemical processes. These changes are expected to influence the biological assemblages within the sediment, which play a key role in the biogeochemical processes due to bioturbation. We performed an in-situ experiment to test the effects of mollusc shell-hash on the bioturbation capacity of the macrofaunal assemblages within the sediments affected by marine aquaculture. The aquaculture facilities chosen were a fish farm in an oligotrophic area of the Mediterranean over a sandy sediment, and a mussel farm in the Atlantic located in an estuary over silty sediment. Mollusc shell-hash promoted macrofaunal assemblages with a high bioturbation potential, regardless of the influence of aquaculture. Nevertheless, in the sediment from the mussel-farm, the shell-hash did not have a marked effect on the macrofaunal assemblages. The effect of shell-hash on promoting macrofaunal communities with a high bioturbation potential capacity is therefore dependent on the existing environmental conditions in the area, including the natural organic matter input and grain size of the sediment. Shell-hash could be used a strategy to improve the ecosystem function of sediments as a circular economy-oriented management practice. This research was funded by the project CGL2015-70136-R from the Spanish National Agency for Research (MINECO/FEDER). CS was funded by the University of Alicante (Ref. UATALENTO 17-11).

Initiatives of artisanal fisheries co-management and the construction of differentiated markets for seafood products have been emerging in different parts of the world, as an institutionalized way of coping with a global fishery crisis. This paper analyses some institutionalization processes of artisanal mollusc fisheries, considering the role of co-management in two Brazilian and Italian protected areas (Resex Pirajubae and Conero Regional Park). Within a theoretical framework aiming at moving beyond the dualism between nature and society, the methodology of multiple-case-study has been used to carry on research about mollusc artisanal fisheries co-management networks in their constitution and development. The paper analyses how these networks are organised in the two contexts and the relations social actors have been developing for a sustainable fishery as a possible way to influence and increase their capacity to address environmental crisis. In the artisanal mollusc fishery co-management experiences, fishers’ participation may favour institutional innovations and the co-management networks stability may be generated by the institutions legitimacy. Furthermore, the case studies offer complementary insights to better understand the linkage between artisanal fishery institutionalization processes, common natural resources co-management and value aggregation for traditional seafood. Artisanal mollusc fishery co-management experiences should be stimulated and investigated since they can help in diagnosing early climate and environmental changes in the oceans.

Restrictions on the use of synthetic molluscicides highlight the importance of developing alternative control methods. Nevertheless, biocontrol agents can be costlier and less effective than synthe...

The article describes features of the operational analysis of valve activity of freshwater (Unio pictorum) and marine (Black Sea mussel Mytilus galloprovincialis) bivalve molluscs for created automated systems of bioelectronic environmental control. The studies used measuring data obtained from long-term field and laboratory experiments using instruments developed by the author. The assessment of the mollusc general behavioral characteristics expressed in the dynamics and amplitude of group valve activity as a response to various effects made it possible to determine typical behavioral response models of toxic effects in the aquatic control environment. For the operational analysis, the main statistical indicators are identified, which are used to create software algorithms for automatic decision-making of the environmental biomonitoring system. As these indicators are used first of all the group time-sliding estimates of the synchronism of mollusc reactions, the data of valve activity averaged in different time intervals and the gape level (group and individual). The existence of established models, specified calculated numerical indicators and their permissible limits will ensure the standardization of the approach to detection of toxic factors and further implementation of such biomonitoring systems at control points.

This study implemented a numerical model to determine the range of dispersion of biodeposits and to identify the accumulation zones produced by the farming of bivalve molluscs in the North and South Bays of Santa Catarina Island, Brazil. We applied the MOHID (MOdelo HIDrodinâmico) physically-based numerical model forced with data from tide gauges located in the mouths of the two bays, which were validated with current and tide measurements inside the bays. This is the first study to use numerical modelling in Santa Catarina Island Bays to predict the influence of bivalve mollusc biodeposit areas. The simulated scenarios suggest that the widest dispersion zones occurred during the spring tide when particles were deposited over a 24 km2 area corresponding to, approximately, 5.5% of the total bay area. The maximum concentration of biodeposits was 50 particles.grid cell−1 and it occurred within a ~4.8 km2 zone. Current velocities were simulated for sheltered and exposed sites and for neap and spring tides in the North and South Bays.

Microbiological contamination of bivalve molluscs is one of the major concerns inherent to food safety, thus depuration is frequently needed to assure food safety levels associated with their consumption. Salinity plays an important role in the metabolic activity of bivalves and as such can influence their depuration capacity. This study aimed to evaluate the effect of salinity (25, 30, 35 and 40) on the efficiency of the depuration process, along with the quality and shelf-life of Crassostrea gigas. For this, a 24-h depuration was carried out, followed by a storage period at 5 ± 1 °C for six days. Microbiological analyses and biochemical parameters related to oxidative stress response were analysed. Escherichia coli load was reduced in only 24 h, disregarding the salinity of the system. After the shelf-life period, the activity of the antioxidant defences at salinities 35 and 40 is higher but is still not sufficient to avoid lipid peroxidation. Over time, there is a decrease in oyster metabolism probably due to being chilled and to the action of exposure to air. In sum, this study suggests salinities between 25 and 30 as preferential for the depuration process of C. gigas and subsequent quality during shelf-life.

Mollusc shells, which are often quite numerous in archaeological sites throughout the Pacific Islands, offer good proxies for assessing environmental change as well as human impact. Documented changes in species size, richness, and abundance have often been interpreted as evidence of resource abuse by shellfish gatherers. While this may be valid in some cases, archaeologists need to consider other variables to explain change (or stability) in shell distribution. A better understanding of ecological and biological (life history) characteristics associated with shell midden deposits, as well as greater awareness of ethnographic and ethnoarchaeological data on the interaction between people and varieties of marine resources, may result in a reinterpretation of past human behavior. A growing interest in indigenous resource management among contemporary Pacific Island communities has led some archaeologists to seek tangible evidence of community resilience and sustainable use of resources in the past. This chapter draws primarily from direct observations and semi-structured interviews among mollusc gatherers in Kiribati, eastern Micronesia, and examines selected case studies of archaeological shell deposits from the Pacific Islands that could shed new light on marine resource management to complement the more widespread research conclusions that depict human impact in largely negative terms.

Ken Mulvaney's long-awaited Murujuga Marni: Rock Art of the Macropod Hunters and Mollusc Harvesters has significant ramifications for Australian art history. On ABC Radio, in 2012, archaeologist Pr...

This letter presents a biomimetic underwater soft robot design with novel propulsion and maneuvering mechanisms. The robot design took inspirations from cephalopod molluscs. The proposed robot comprises a soft mantle structure with multiple built-in soft actuators, which could deform to provide steering and maneuverability for underwater locomotion. Smart sensors are embedded into the soft mantle to provide real-time feedback to the controller. Underwater thrust is generated by a novel vortex-based soft tail mechanism also inspired by molluscs. The tail mechanism incorporates an electric motor sealed inside a continuum chamber, and rotational motion from the motor is transmitted to the soft-bodied tentacles, which generate a vortex to produce thrust. The resulting soft robot is incorporated in a seamless body, while both propulsion and steering are generated by soft-body deformation. To investigate the novel vortex-based biomimetic propulsion generation mechanism, an analytical model was developed to capture the relation between input motor speed and the resulting thrust force. The entire robot was fabricated using 3-D-printing and soft-material molding. The fabricated robot components and the assembled system were both validated through experiments. The results show that the mollusk-inspired robot could achieve underwater maneuverability by bending the four actuators, and the measured results match well with the proposed analytical mode. The proposed design could easily be repeated by anyone with access to a consumer-grade 3-D printer, enabling a wide range of biomimetic robot enthusiasts to investigate in the new mechanism for underwater propulsion and maneuvering.

Human enteric viruses, such as norovirus and hepatitis A virus, are spread by a variety of routes including faecal-oral transmission. Contaminated bivalve shellfish are regularly implicated in foodborne viral disease outbreaks internationally. Traditionally indicator bacteria, the coliforms and Escherichia coli, have been used to detect faecal pollution in growing waters and shellfish. However, studies have established that they are inadequate as indicators of the risk of human enteric viruses. Bacteriophages have been identified as potential indicators or surrogates for human enteric viruses due to their similarities in morphology, behaviour in water environments and resistance to disinfectant treatments. The somatic coliphages, male-specific RNA coliphages (FRNA coliphages) and the bacteriophages of Bacteroides are the groups recognised as most suitable for water and shellfish testing. In this review, we discuss the rationale and supporting evidence for the application of bacteriophages as surrogates for human enteric viruses in shellfish under a variety of conditions. There is some evidence to support the validity of using bacteriophage levels to indicate viral risk in shellfish in highly contaminated sites and following adverse sewage events.

Human-induced climate change and ocean acidification are global environmental phenomena with a common driver: anthropogenic emissions of carbon dioxide. Both processes potentially threaten the Mediterranean bivalve mollusc aquaculture sector, which is economically relevant to several regions and countries. Detrimental effects on bivalve mollusc species might arise from the associated increase in sea surface temperature, pH reduction, higher frequency of extreme climatic events, and possible synergies with other nonclimatic stressors, such as harmful algal blooms and mollusc diseases. This paper presents the results of a questionnaire-based study of Mediterranean bivalve mollusc producers from 12 coastal regions and six countries, the latter including those with the highest production share in the Mediterranean region. This study aims to assess knowledge and perception of threat of climatic and nonclimatic environmental stressors within the Mediterranean aquaculture industry. Furthermore, it collects information about the (geographical) impacts of summer heat waves and ocean acidification. The results suggest that ocean acidification is still a relatively unknown phenomenon and generally poorly understood. Moreover, it is considered a secondary threat compared with other pressures. Summer heat waves are presently perceived as the highest threat, having been observed in a majority of the studied production sites in past years, with effects on seed (spat), adult mortality, and byssus attachment.

The British Isles has perhaps the most comprehensively mapped land and freshwater mollusc fauna at a national level with a history extending back 120 years. This results from the insight, dedication and enthusiasm of a relatively small group of almost exclusively amateur malacologists. The national distribution atlases published in 1976 for the non-marine fauna (Kerney, 1976) and in 1982 for the marine fauna (Seaward, 1982) represent the culmination of their work. This paper focuses mainly on the characters contributing towards non-marine mapping until 1960 and their achievements, although the inception and development of the scheme is briefly discussed. A history of marine mollusc mapping in this country, the foundations for which were laid in the 1920s, is also given.

The effects of three copper-based fungicides on feeding by four terrestrial molluscs (two slugs and two snails) were assessed in laboratory choice and no-choice tests. These products functioned effectively as short-term feeding deterrents. However, a copper hydroxide-based fungicide was more persistent than copper octanate- and copper diammonia diacetate-based fungicides under field conditions. Tests with foliage treated in the field and fed to Leidyula floridana and Lissachatina fulica showed that significant feeding suppression persisted for several days. We also determined that copper hydroxide was repellent, affecting movement of L . floridana slugs independent of food. Further, we assessed copper hydroxide effects with and without iron phosphate molluscicide bait. Copper hydroxide alone significantly suppressed foliage consumption, but did not affect slug survival. Iron phosphate bait alone caused slug mortality, and significantly suppressed feeding, but only after 24 h. Significantly improved foliage protection, relative to iron phosphate bait application alone, was attained when copper hydroxide repellent was used simultaneously with iron phosphate bait. Where terrestrial molluscs are a plant protection issue, it appears that ancillary benefit can be derived from using copper hydroxide fungicides. These data provide evidence for the potential application of the “push–pull” or “stimulo-deterrent” concept relative to mollusc management; plant protection may be enhanced when attractant and repellent treatments are applied simultaneously.

BACKGROUND: Snails and slugs are terrestrial gastropods representing an important biotic stress that adversely affects crop yields. These pests are typically controlled with molluscicides, which produce pollution and toxicity and further induce the evolution of resistance mechanisms, making pest management even more challenging. In our work, we have assessed the efficacy of two different plant defence activators, menadione sodium bisulphite (MSB) and 1,2,3-benzothiadiazole-7-thiocarboxylic acid S-methyl ester (BTH), as inducers of resistance mechanisms of the model plant for defence, Solanum lycopersicum, against the generalist mollusc Theba grasseti (Helicidae). The study was designed to test the feeding behaviour and choice of snails, and also to analyse the expression profile of different genes specifically involved in defence against herbivores and wounds. RESULTS: Our data suggest that, through the downregulation of the terpene volatile genes and the production of proteinase inhibitors, treated MSB plants may be less apparent to herbivores that use herbivore-induced plant volatiles for host location. By contrast, BTH was not effective in the treatment of the pest, probably owing to an antagonistic effect derived from the induction of both salicylic-acid-dependent and jasmonic-acid-dependent pathways. CONCLUSIONS: This information is crucial to determine the genetic basis of the choice of terrestrial gastropod herbivores in tomato, providing valuable insight into how the plant defence activators could control herbivore pests in plants. Our work not only reports for the first time the interaction between tomato and a mollusc pest but also presents the action of two plant defence inductors that seems to produce opposed responses by inducing resistance mechanisms through different defence pathways. © 2015 Society of Chemical Industry Supporting information may be found in the online version of this article.

The present study deals with biomonitoring to know mollusc species as an indicator. In the present study, presence, absence and abundance of particular gastropod and bivalve species were identified in the different banks of river Ganga. The study was carried out at two experimental sites, Sodepur (Exp-1) and Khardah (Exp-2), West Bengal, India as the area exhibits a major sewage water outfall in the river compared with upstream control site, Kalyani (Cont-1) and downstream control site, Batanagar (Cont-1). The present biomonitoring shows qualitatively and quantitatively that in experimental no mollusc species were observed near the wastewater discharge area into the bank of river Ganga at Khardah while both sites of the sewage discharge area into the bank of river Ganga at Sodepur particular gastropod Bellamya sp. were observed when compared to control area. The highest variety and total nos of gastropods and bivalves (280 nos) were recorded in the upstream at Kalyani and lowest variety and total nos of only gastropods (150 nos) were recorded in the downstream at Batanagar. The present biomonitoring work was a preliminary observation to know sensitive and tolerant or accumulator mollusc species in the bank of river Ganga from a stretch of Kalyani (upstream) to Batanagar (downstream) in between urban wastewater discharge area (Sodepur and Khardah). Further researches must be relevant in relation to biomarker assessment with the physico-chemical factors and stress tolerant detoxification mechanism of particular mollusc species.

The acute apoptotic response to genotoxic carcinogens animal model has been extensively used to assess the ability of drugs and natural products like dietary components to promote apoptosis in the colon and protect against colorectal cancer (CRC). This work aimed to use this model to identify the main chemopreventative agent in extracts from an Australian mollusc Dicathais orbita, while simultaneously providing information on their potential in vivo toxicity. After 2 weeks of daily oral gavage with bioactive extracts and purified brominated indoles, mice were injected with the chemical carcinogen azoxymethane (AOM; 10 mg/kg) and then killed 6 hours later. Efficacy was evaluated using immunohistochemical and hematoxylin staining, and toxicity was assessed via hematology, blood biochemistry, and liver histopathology. Comparison of saline- and AOM-injected controls revealed that potential toxic side effects can be interpreted from blood biochemistry and hematology using this short-term model, although AOM negatively affected the ability to detect histopathological effects in the liver. Purified 6-bromoisatin was identified as the main cancer preventive agent in the Muricidae extract, significantly enhancing apoptosis and reducing cell proliferation in the colonic crypts at 0.05 mg/g. There was no evidence of liver toxicity associated with 6-bromoisatin, whereas 0.1 mg/g of the brominated indole tyrindoleninone led to elevated aspartate aminotransferase levels and a reduction in red blood cells. As tyrindoleninone is converted to 6-bromoisatin by oxidation, this information will assist in the optimization and quality control of a chemopreventative nutraceutical from Muricidae. In conclusion, preliminary data on in vivo safety can be simultaneously collected when testing the efficacy of new natural products, such as 6-bromoisatin from Muricidae molluscs for early stage prevention of colon cancer.

The phylum Perkinsozoa includes well-known parasites of commercially important species of molluscs in aquaculture, such as

Marine mollusc production contributes to food and economic security worldwide and provides valuable ecological services, yet diseases threaten these industries and wild populations. Although the infrastructure for mollusc aquaculture health management is well characterized, its foundations are not without flaws. Use of notifiable pathogen lists can leave blind spots with regard to detection of unlisted and emerging pathogens. Increased reliance on molecular tools has come without similar attention to diagnostic validation, raising questions about assay performance, and has been accompanied by a reduced emphasis on microscopic diagnostic expertise that could weaken pathogen detection capabilities. Persistent questions concerning pathogen biology and ecology promote regulatory paralysis that impedes trade and which could weaken biosecurity by driving commerce to surreptitious channels. Solutions that might be pursued to improve shellfish aquaculture health management include the establishment of more broad-based surveillance programmes, wider training and use of general methods like histopathology to ensure alertness to emerging diseases, an increased focus on assay assessment and validation as fundamental to assay development, investment in basic research, and application of risk analyses to improve regulation. A continual sharpening of diagnostic tools and approaches and deepening of scientific knowledge is necessary to manage diseases and promote sustainable molluscan shellfish industries.

The distribution and species richness of aquatic molluscs were analysed within a 186-km-long section of a large (755-km-long) lowland river floodplain using GIS maps. Special attention was paid to threatened species. An attempt was made to identify local ‘hotspots’ of molluscan diversity and to determine the most important areas for conservation based on species richness, number of threatened species and indices of synthetic conservation (Q) and centres of population density (ICD). Over four years of investigation, carried out in 176 water bodies, a rich malacofauna was identified: 58 species including 20 of elevated conservation concern. GIS maps revealed numerous ‘hotspots’ of mollusc species richness and higher incidence of threatened species, as well as areas characterized by raised Q and ICD indices. Water body size and hydrological connectivity positively influenced species richness and Q values. The highest values of these variables were found in large water bodies having limited surficial connectivity with the river channel. Species richness, numbers of threatened species, and Q and ICD values were significantly higher in younger permanent water bodies compared with semi-permanent or temporary ones representing advanced successional stages. Spatial visualization data collected in the study area indicate that the most valuable sites for the conservation of aquatic molluscs include both sides of the river in the lower part of the middle stretch of the lower Bug River valley. Copyright © 2013 John Wiley & Sons, Ltd.

Three species of Boccardia (B. polybranchia, B. pseudonatrix and B. proboscidea) were associated with mollusc shells on the south and south-east coasts of South Africa. Boccardia polybranchia was widely distributed along the coast and falls within the known distribution range of this species. Comparisons with material from other, international, locations showed that some specimens have been misidentified. No characters could be found to characterize distinct species for different regions within the range of B. polybranchia, as currently recognized. Boccardia pseudonatrix was found only at the most eastern site, increasing its known distribution range. Boccardia proboscidea, a non-indigenous species, was found only on abalone farms and was most abundant in the west.

Entomopathogenic and molluscoparasitic nematodes are important parasites of many insects and molluscs, respectively. Due to their infectivity, the possibility of mass production by industrial techniques and the relative safety to nontarget organisms and environment, these organisms represent an attractive agent for biological control of many pests. This chapter summarises the current knowledge of the diversity of these organisms. In this chapter, we review the recent advances in production, storage, application techniques genetic improvement and safety of these organisms.

Shellfish aquaculture forms a small but expanding section of Scotland's seafood production. This production benefits from a good health status with the absence of notifiable diseases, except for localised cases of Bonamia ostreae . In this paper we review factors that could lead to the introduction and/or spread of key diseases in order that associated risk can be minimised. We selected B. ostreae and Bonamia exitiosa , Marteilia refringens and oyster herpesvirus as key pathogens; all of which have been found in and are notifiable within the United Kingdom. Vulnerabilities of molluscs farmed in Scotland to these pathogens are reviewed, as are sources of infection in neighbouring areas from which the pathogens might be introduced. We then examine: key pathways of introduction, whether conditions are suitable for the pathogens to persist in Scotland, potential for spread within Scotland and likelihood, and consequence of disease outbreaks. The major pathway for potential introduction is with the import of Pacific oysters from hatcheries. B. ostreae is the pathogen that has the highest probability of causing disease, however B. ostreae is restricted to native oysters whose production in Scotland is very small. Oyster herpesvirus could cause far larger economic consequences due to the size of the Pacific oyster industry but is less likely to invade. Therefore risks for B. ostreae and oyster herpesvirus are similar. Risks could change if imports are sourced from higher risk areas or pathogens spread in areas where currently used hatcheries are located. Water temperature in Scotland is marginal for oyster herpesvirus and M. refringens so continuation of warming trends could increase risks from these pathogens.

Article history: Objective: Some of the products derived from marine organisms have been recommended in alternative system of medicine especially Siddha medicine for several treatments. Among the marine molluscs, Cypraea moneta shell has been used as siddha medicine from ancient days. But no systematic study has been done on its efficacy as antipyretic, wound healing and as antimicrobial agent. In the present study, the protective action of processed shell powder of C. moneta was evaluated by us in an animal model for the above treatments. Methods: C. moneta shell powder was prepared by standard method described in Siddha medicine. Then the antipyretic, wound healing as well as antimicrobial effect of the processed powder was tested in Wister albino rats. Results: By the intravenous injection of yeast cell suspension into albino rats, the antipyretic effect of the shell powder given orally was studied by various concentrations of 0, 10, 20 and 30 mg/ml. The body temperature of the albino rat became normal within a short duration (3h). The wound healing effect of the shell powder was very effective. In the thigh region 2 cm wound was made and the different dosages of shell powder (C -Control, SD - Single dose, DD -Double dosage and TD -Triple dose/day) were applied externally as ointment. The scar was produced in eighth day onwards in DD and TD. Antimicrobial activity was studied in three different oppurtunistic human pathogens such as Micrococcus sp., Proteus vulgaris and Salmonella abory in different concentrations (2, 3, 4 and 5% w/v) of C. moneta shell powder extract. Among these, Proteus vulgaris showed the maximum zone of inhibition (15mm size) against 5% w/v concentration, followed by Micrococcus sp. (12mm) and S. abory (10mm) against the same concentration. Conclusions: The present observation suggested that, processed C. moneta shell powder can be used as an alternative medicine, and it has antipyretic, wound healing as well as antimicrobial properties.

The ability of bivalve culture in the proximity of an open water fin fish farm to reduce the environmental impact caused by organic wastes was tested. The experiment involved floating net cages containing cultured gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax) in the western Mediterranean. Two bivalve species, oyster (Ostrea edulis) and mussel (Mytilus galloprovincialis), were deployed for 3 months along a distance transect running from 0 to 1800 m from the fish cages. Shell growth, flesh dry weight, the concentration of stable isotopes of carbon and nitrogen, and metal accumulation (Cd, Pb, Cu and Zn) in the bivalves were analyzed. Bivalves showed significant growth compared with their respective starting sizes, although closeness to the fish farm did not enhance such growth. The stable isotopes content indicated that there was no relationship between the main input of organic matter from the fish farm (the feed) and the trophic behavior of the bivalves. Neither did metal accumulation show a trend along the distance gradient from the fish farm. All the results were consistent in indicating that neither oysters nor mussels fed on fin fish farming wastes. This work demonstrates that the polyculture of fin fish and bivalves does not represent an appropriate tool for reducing the environmental impact of fin fish aquaculture in open water. The work was supported by the Programme AlBan, the European Union Programme of High Level Scholarships for Latin America (FNM scholarship No. E07D401236EC) and by FPU predoctoral grant of the Ministerio de Ciencia y Tecnología from Spain.

Las principales actividades acuicolas en el estuario de Quempillen son la acuicultura de ostras, Ostrea chilensis, y del alga Gracilaria chilensis. La intervencion antropogenica al interior del estuario genera cambios significativos a nivel del sedimento y de los contenidos de materia organica.

Molluscs are known to be seriously affected by trace amounts of environmental pollutants such as tributyltin at concentrations in seawater that are below the level of detection by all but the most sensitive chemical analytical techniques. This extreme sensitivity by molluscs has led to use of both adults and larvae as biomonitors for environmental pollution. Mollusc aquaculture has led to an increasing demand for commercial hatcheries to supply seed stock, including selected genetic lines of spat and juveniles. It is becoming apparent that many of the unexplained “crashes”, ill thrift or failures of larvae to metamorphose in such hatcheries are primarily due to their being compromised for a range of reasons including traces of inhibitory or toxic substances in the water supply. Because dead and dying larvae are ideal substrates for bacterial and ciliate growth, such invaders are often assumed to be the primary cause of the problem and this hinders finding a solution. In addition, many of the toxins which may be implicated in crashes are sporadic in occurrence and are both difficult to detect and hard to remove from the water supply. This paper provides evidence for these toxic effects and suggests ways of reducing the problems.

Premeditated introductions of non-indigenous molluscan shellfish species have been important in establishing several substantial fisheries. The North American fishery for Crassostrea gigas developed from active introductions that began in the early part of this century and continued until 1978. More recently C. gigas has been introduced to many sites in Europe, South Africa, South America, the Mediterranean, and the Indian and Pacific Oceans. The European flat oyster, Ostrea edulis, has been successfully introduced to the state of Maine. An internationa code of practice for examining and effecting intentional introductions has been developed which recommends a combination of quarantine procedures and hatchery rearing to avoid accidental introduction of associated species and disease organisms. Several nations have developed comprehensive legislation to control movement of non-indigenous species. Active movement of species for culture purposes continues, especially in Europe and the Pacific Islands.

Background: Bellamya bengalensis, an edible bivalve mollusc is traditionally used in the treatment of joint pain, bone fracture, jaundice and eye infections. Present study was designed to find out the most potent analgesic fractions derived from the body mass of Bellamya bengalensis.Methods: The test specimen was collected, identified and fractionated with solvent medium like, phosphate buffer saline (PB), ethyl acetate (EB), methanol (MB) and chloroform (CB). Protein concentration of each fraction was determined. The antinociceptive activities were measured either by thermal models like, hot plate and tail immersion (central analgesic action) or by chemical model like acetic acid induced writhing (peripheral analgesic action) in mice. Diclofenac sodium was used as analgesic standard.Results: Significant peripheral and central analgesic activity showed by phosphate buffer saline fraction at 100mg/kg, even better than diclofenac standard at 10mg/kg. In hot plate and tail immersion tests, phosphate buffer saline showed the highest activity followed by methanol, chloroform and ethyl acetate fraction respectively. However, in case of peripheral analgesic experiment, phosphate buffer fraction exhibited maximum writhing inhibitory properties and that was followed by chloroform, methanol and ethyl acetate fraction respectively.Conclusions: Phosphate buffer saline fraction of Bellamya bengalensis showed maximum potential central and peripheral analgesic activity than any other fractions.

In the context of infectious diseases in mollusc and shrimp aquaculture, research must be focused on diagnosis for zoosanitary controls but also on obtaining resistant animals. This last strategy depends heavily on the development of knowledge about marine invertebrate immunology. With the establishment of purification protocols for the main invertebrate pathogens, progress has been made in the study of host-pathogen interactions at cellular and molecular levels and in identifying immune effectors involved in the destruction of pathogens. Recent information on molluscs and crustaceans is presented, concerning both hemocyte studies and cellular defence functions and humoral effectors, with special reference to their application to selection of pathogen-resistant animals. With this aim, research prospects will essentially be devoted to the identification and characterization of immune genes, either specific or heterologous, which could be candidates for mollusc and shrimp genetic transformation.

Tetrodotoxin, a violent neurotoxin, is present in puffer fish and may occur in a variety of marine animals. Outbreaks of human tetrodotoxin poisoning, following consumption of marine organisms other than puffer fish, has been rare. We here report an outbreak of tetrodotoxin poisoning fol lowing ingestion of gastropod molluscs and its clinical fea tures are discussed. A 71-year-old woman was admitted with hypertension and other neurological symptoms developing after inges tion of some molluscs. A further 16 cases were also found to have typical symptoms of tetrodotoxication after mol lusc consumption. Clinical features in these 17 cases were similar to those conventionally found in tetrodotoxin poisoning, except that there was hypertension in eight cases (47%). All except one case had mild poisoning and recovered well. The molluscs consumed comprised two different species: Nassarius castus and Nassarius conoidalis, both of which were shown to contain various amounts of tetrodotoxin. It is concluded that tetrodotoxin poisoning following mollusc consumption is a possibility. Hypertension, as an unusual feature in tetrodotoxication, is frequent in this outbreak, and should be looked for in future cases. The explanation of hypertension in tetrodotoxication may come either from an exaggerated response to sympathetic stimuli, or due to various responses of the vasomotor centre to a small dose of tetrodotoxin. Further studies are required to answer this question.

Concentrations of Cd, Pb, Zn, Cu, Mn, and Fe in soft tissue and byssal threads of Perna perna from the Gulf of Aden, Yemen, were determined by atomic absorption spectrophotometric (AAS) method. Significant inter-regional differences in the metal concentrations studied in both soft tissue and byssus were identified. The concentration of Cd was an order of magnitude greater in soft tissue than in byssal threads. Statistically significant correlations (p

Cephalopods provide numerous examples of behavioral and neural plasticity and richness of the behavioral repertoire that has been claimed in favour of cognitive capabilities. Here we revise the most recent knowledge on octopus cognition and recognition processes. The examination of data and observations available provide the basis for asking new stimulating questions about the cognitive abilities of octopuses and their allies and open novel scenarios for future comparative research.

Summary Farming of crustaceans and molluscs in Southern Africa is not well developed, but it is likely to intensify in coming years. The pressure to introduce new candidate species to satisfy specific culinary demands or improve bulk yields and efficiencies is also expected to increase. This paper stresses some of the problems associated with the intentional or accidental introduction of exotics, and translocation of local species into catchments where they did not previously occur. Several freshwater crustacean species have already been introduced into eastern and southern Africa, often without the knowledge and permission of the authorities. Introduced freshwater crayfish constitute a new element of African fauna, as such species were not present in the continent originally. Introduced species from North America and Australia could thus be seen as using some aspect of the resources which are under-utilized by existing species in Africa. This paper, however, argues that introduced species are likely to c...

Current research indicates that customer-product interaction in the new product development life cycle strongly influences the success of a product in the marketplace. B2P Limited is a New Zealand biotechnology start-up specialising in microbiological products for testing of bacteria and pathogens in the global food and water based industries. “Water and Food Safety Testing Products for the New Zealand Mollusc Aquaculture Organisation: A Case Study in New Product Innovation” is an exploratory applied research project using case research methodology combining qualitative and quantitative methods for data gathering and analysis. The literature review has revealed that the global aquaculture industry is in need of improved water and food testing methods. The New Zealand aquaculture industry is growing rapidly and has similar needs. The objective of the research is to identify the criteria for potential adoption of three microbiological testing products in the mollusc sector of the New Zealand aquaculture industry. Four New Zealand commercial aquafarms were selected to participate in the field trials of three water and food testing products.The central aspect of the research undertook to identify, collect, analyse and report information taken from customer product interaction to establish criteria for adoption and potential use of product benefits. The research encompassed in the current study, sought to provide some information on the cost benefit scenarios and general applicability of the B2P tests within the aquaculture environment. The results of the field research are used to indicate the economic advantages or disadvantages of product use in comparison with existing products and processes in each of the aquafarms. A key potential benefit of the use of the B2P products is the improved quality of delivered shellfish as a result of a reduced risk of harvesting contaminated shellfish. A second key benefit is the increased revenues due to lower rejection in the market. Thirdly, the use of the B2P products gives the aquafarmer the capability to reduce the number of lost harvests and as a result to reduce wastage, reduce re-work and reduce the costs of production. Improved shellfish quality may increase volume of sales and open new markets. Improved quality of delivery may increase distributor orders.The knowledge gained should lead to potential B2P product and aquafarming product improvements and a greater knowledge of the criteria for B2P product adoption by potential markets in the global aquaculture industry. The research findings support the literature that customer-product interaction early in the new product development life cycle can improve the likelihood of new product success in new markets.

The development of new methodologies for diagnosis of infectious diseases of molluscs and shrimps is related to progress in biotechnology and molecular biology. The different kinds of immunoreagents and nucleic-acid probes and the respective advantages and disadvantages of immunological and nucleic-acid hybridization-based methods are described and analysed in terms of developments and applications in marine invertebrates aquaculture.

In November 2002, the tanker 'Prestige' released about 19,000 tonnes of a heavy fuel oil (no. 6) before sinking with about 58,000 tonnes of its cargo, 135 miles from Cabo Finisterra (Spain). A considerable part of the released fuel oil reached the Galician coast, causing a heavy black tide and an ecological disaster. Although the black tide did not reach the NW coast of Portugal, it is possible that some of the fuel oil or its components also arrived to this area directly through the sea water and/or indirectly through the food chain. Therefore, the aim of this study was to investigate possible changes in two widely used biomarkers, the activity of the enzymes cholinesterases (ChE) and glutathione S-transferases (GST), of three molluscs (Mytilus galloprovincialis, Nucella lapillus and Monodonta lineata) from wild populations of the NW Portuguese coast in relation to the 'Prestige' oil spill. Molluscs were collected seasonally before (autumn 2002) and after (winter 2002/2003), spring and summer 2003) the oil spill at several sites along the Portuguese NW coast. Enzymatic activities determined before the accident were compared with those determined at different times after the oil spill taking into consideration abiotic factors. Information from different parameters was integrated by Redundancy Analysis and Principal Response Curves (PRC). Results show that GST and ChE activities were influenced by abiotic factors. Despite this influence, the results of PRC analysis also suggest that some of the fuel oil reached the NW Portuguese coast changing the patterns of ChE and GST activities of local populations of rocky shore species. Furthermore, the present study highlights the need of long-term monitoring with wild populations to assess both historical and punctual effects of pollution in the marine environment. (C) 2009 Elsevier Ltd. All rights reserved.