Search

The present paper deals with the distribution of sediment and sediment-bound nutrients in two important coastal lagoons of southern Kerala such as the Ashtamudi Estuarine Lagoon in the Kollam district and the Kadinamkulam Lagoon in the Thiruvananthapuram district. Among the two lagoons, the former is coast perpendicular, and the latter is coast parallel. An analysis of the textural characteristics reveals that, in both lagoons, the estuarine mouth and areas close to it are dominated by sand and sand-rich sediment species, indicating a high-energy depositional regime prevailing the region. On the other hand, the silt and clay dominant arms are almost sheltered and enjoy a low-energy depositional environment. The nutrient and organic carbon contents in the sheltered areas are significantly higher than the most dynamic high-energy estuarine mouth regions. This peculiar behaviour of these coastal water bodies has to be given adequate importance while laying down strategies for the conservation and management of these fragile aquatic systems in the south-western coast of India in particular and tropical coasts of the world in general. [ABSTRACT FROM AUTHOR]

ABSTRACT Hepatitis C is a global health problem with a worldwide prevalence of about 3% (around 170 million people). Hepatitis C virus (HCV) is major concern in the Maghreb countries, Algeria, Libya, Mauritania, Morocco, and Tunisia, but no detailed description of its epidemiology in the region is available. In the present review, a systematic search was undertaken covering HCV data available in peer-reviewed databases as well as institutional reports and regional conference meeting abstracts from the Maghreb countries. Reports written in English and French were included in this analysis. Estimates of national and regional prevalence of HCV infection (based on anti-HCV antibody) and of the size of patient populations were performed. In addition, the molecular features of the circulating viral strains in the region are discussed. A substantial proportion, 1.2-1.9% of the Maghreb inhabitants, have anti-HCV antibodies. Genotype 1b predominates among viral strains in all countries except in Libya, where genotype 4 is dominant as in neighboring Egypt. This epidemiological situation is of significant concern, and requires urgent, broad, and active intervention for the prevention and control of HCV. More specifically, the application of state-of-the-art hygiene procedures and rigorous controls in medical disciplines such as hemodialysis, transfusion, endoscopic procedures, and dentistry is necessary to reduce significantly the number of new infections in the region. J. Med. Virol. 85:1542-1549, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Hepatitis B virus ( HBV) represents an important health problem in the Maghreb countries, Algeria, Libya, Mauritania, Morocco and Tunisia, but no detailed synthesis of its epidemiology is available. In this review, we systematically searched for data about HBV in the Maghreb in peer-reviewed databases and included in our analysis works written in English and French, as well as institutional reports and regional conference meeting abstracts. We estimated national and regional prevalence of chronic HBV infection. In addition, we discuss molecular features of the viral strains circulating in the region. Data analysis suggests that in the Maghreb region HBs antigen carriage concerns 1.8-4.9% of the population for an estimated number of 2.7 million persons. Genotype D, subtype D7, is predominant and mutations in the precore region of HBV genome are highly prevalent. This epidemiological situation requires obviously widespread active interventions for prevention and control. In addition, anti-hepatitis B vaccination programme should be applied with the utmost discipline in the five countries considered in this present review. This systematic review will, hopefully, increase knowledge at disposal of Public Health authorities, enabling better resource allocation and healthcare delivery. The present synthesis intends to stimulate policies aiming at preventing the spread of HBV, keeping in mind that eradication of the virus from Maghrebi populations should be the ultimate objective of Public Health authorities. [ABSTRACT FROM AUTHOR]

Seagrass habitats are being lost throughout the world and the invasive alga C. taxifolia has often been implicated in seagrass declines. Although C. taxifolia can impact a variety of species, evidence for its effects on seagrasses is largely correlative. This study combined observational studies and manipulative experiments done over many years to test hypotheses about effects of C. taxifolia on two Australian seagrasses, namely Posidonia australis and Zostera capricorni. Results indicated that C. taxifolia is not having adverse impacts on the coverage of these seagrasses in the sites studied. Rather, C. taxifolia appears to be an opportunist, persisting longer and its coverage being greater in previously non-vegetated sediments than amongst seagrasses. C. taxifolia co-existed with P. australis and did not cause reductions in the cover of the seagrass. Outcomes of experimental manipulations of C. taxifolia amongst Z. capriconi were less clear due to losses of Z. capriconi in all plots, regardless of the presence of C. taxifolia. It was possible that C. taxifolia may have enhanced the decline in canopy cover of Z. capricorni, but the presence of alga did not alter the final fate of Z. capricorni. There was also no evidence that long-term areal coverage of P. australis or Z. capriconi has been affected by the introduction of C. taxifolia in the embayments studied. A review of literature on effects of species of Caulerpa on seagrasses provided limited experimental evidence for negative impacts of this genus on seagrass abundance. [ABSTRACT FROM AUTHOR]

In the last decade, the trade of marine ornamental species has experienced a significant expansion worldwide; however, this industry still relies on a large number of unsustainable practices (e.g., cyanide fishing, overexploitation of target species) and needs to shift its operations urgently to avoid collapsing. Under this scenario, traceability and certification emerge as important management tools that may help this industry to shift toward sustainability. This industry relies on the trade of thousands of small-sized species that are traded live on a unitary basis with high market value. These features, along with a fragmented and complex supply chain, make the traceability of marine ornamental species a challenging task. This study presents the most commonly used methods to trace aquatic organisms and discusses their suitability to trace marine ornamental species. The use of bacterial fingerprints appears to be the most promising method to successfully trace marine ornamentals, but it is most likely that a combination of two or more traceability methods need to be implemented to cover all the unique features displayed by the live trade of marine ornamental species. [ABSTRACT FROM AUTHOR]

Biological invasions modify the quality and supply of detrital subsidies to aquatic and terrestrial ecosystems. Where the invader has very different traits to native species, major changes in associated consumer communities may result, as a consequence of differences in their nutritional value and effects on the sedimentary habitat. We assessed how the replacement of seagrasses with the invasive alga Caulerpa taxifolia in modified Australian estuaries influences invertebrate communities of mudflats that are subsidized by detritus from submerged aquatic vegetation. Two months after experimental enrichment of sediments with high (60 g dry weight per 0.25 m plot) or low (30 g dry weight) quantities of either non-native C. taxifolia or native Posidonia australis or Zostera capricorni detritus, there were positive effects of detrital addition on invertebrate abundance that occurred irrespective of the resource added. By 4 months after addition, however, detritus from invasive C. taxifolia had produced effects on benthic communities that could not be replicated by detritus from either of the native seagrasses. Plots receiving the high loading of C. taxifolia detritus contained fewer invertebrates than plots of the other treatments, perhaps due to the induction of sediment hypoxia. The pattern, however, reversed at low detrital loading, with the plots receiving 30 g of C. taxifolia containing more invertebrates and more taxa than the other plots, presumably due to the greater resource availability for detritivores. Our results demonstrate that replacement of native seagrass with invasive algal detritus can have large impacts on sediment-dwelling communities. [ABSTRACT FROM AUTHOR]

Early in the history of life, algae changed the planet's atmosphere by producing oxygen, thus paving the way for the evolution of eukaryotic organisms. In an era in which the consumption of fossil fuels is a prime topic of concern, few people realize that the oil we currently exploit comes mostly from Cretaceous deposits of marine algae. Moving from ancient times to the present, the algae remain more important than most people realize. Today, the production of oxygen by algae (ca. 50% of all oxygen production) is another reason for saying 'our lives depend on algae.' Those who love seafood should thank the algae because algae are the primary producers upon which aquatic ecosystems depend. Thanks should come from all who are vegetarians or omnivores, because all land plants derive from a freshwater class of green algae and all land-animals-including the cows that provide the steaks for meat-lovers-depend directly or indirectly on land plants for food and often for shelter as well. As we use up the oil deposits provided by the ancient algae, we are turning to the modern algae for help. Given the photosynthetic abilities of the algae, they are one of the major focuses for sustainable biofuel production and CO consumption. Finally, the algae that give us the air we breathe, the food we eat, and the fuel for our cars (past and, perhaps, future), are also a source of active pharmaceutical compounds that can be used against drug-resistant bacterial strains, viruses (including Herpes Simplex and AIDS), and cancers. Roses are pretty and oak trees are impressive, but no other groups of 'plants' have done so much, for so long, and, for so many as have the algae! [ABSTRACT FROM AUTHOR]

Food intake ( FI) and gut evacuation ( Rg) were measured in larvae of P seudoplatystoma punctifer (4.5-18.4 mm SL) fed A rtemia nauplii, taking advantage of the translucence of their abdominal region to achieve this in a non-destructive way, using digital photographs and mathematical reconstruction of gut volume content (ellipsoidal and cylindrical models for stomach and intestine respectively). The inaccuracy of the method, with reference to counts of nauplii following fish dissection, was low (2.9 ± 1.5%) and independent of fish size ( P = 0.6153). Pigmentation hampered measurement in fish >18-19 mm SL. Anaesthesia was needed in fish >9.5 mm SL, thereby preventing the measurement of Rg in individual fish. The FI increased rapidly during the ontogeny, passing from <7% M at 0.6 mg, to 14% M at 1 mg and 21% M at 15-40 mg, and then decreased slightly in larger fish. At 28.5°C, Rg (% M h−1) was modelled as Rg = −8.22 + 12.11 log FI + 6.30 log M - 12.67 (log M)2 ( R2 = 0.904, d.f. = 27, with FI in% M and M in mg). Extrapolations of Rg over 24 h gave estimates of daily food rations that fit well with those measured in cannibalistic P . punctifer. [ABSTRACT FROM AUTHOR]

The invasion of the aquarium strain of the green alga Caulerpa taxifolia and subsequent alteration of community structure in the Mediterranean Sea raised awareness of the potential for non-native seaweeds to impact coastal communities. An introduction of C. taxifolia in southern California in 2000, presumably from the release of aquarium specimens, cost ~$7 million for eradication efforts. Besides C. taxifolia, other Caulerpa species being sold for aquarium use also may have the potential to invade southern Californian and U.S. waters. Surveys of the availability of Caulerpa species in southern California aquarium retail stores in 2000-2001 revealed that 26 of 50 stores sold at least one Caulerpa species (52 %) with seven stores selling C. taxifolia. In late 2001, California imposed a ban on the importation, sale, or possession of nine Caulerpa species; the City of San Diego expanded these regulations to include the entire genus. To determine the effectiveness of the California ban, we resurveyed Caulerpa availability at 43 of the 50 previously sampled retail stores in southern California in ~2006, ~4 years following the ban. Of the 43 stores, 23 sold Caulerpa (53 %) with four stores selling C. taxifolia. A χ test of frequency of availability before and after the California ban suggests that the ban has not been effective and that the aquarium trade continues to represent a potential vector for distributing Caulerpa specimens, including C. taxifolia. This study underscores the need for increased enforcement and outreach programs to increase awareness among the aquarium industry and aquarium hobbyists. [ABSTRACT FROM AUTHOR]

The reproductive state of the commercial sea urchin Paracentrotus lividus was investigated during one year along a sector of the Ionian Sea of the Apulia region (Southern Italy). Gonadosomatic index, Repletion index and histological methods, categorized by four stages for females and two for male specimens were utilized to assess the reproductive cycle throughout an entire year with monthly sampling in four sites situated to north and south of Torre Suda (Gallipoli Municipality, Province of Lecce). The four populations exhibited similar reproductive pattern, having mature gonads and gonadal reconstitution during almost all months. The population from south of Torre Suda in August and March had the highest Gonadosomatic index values, the highest Gonadosomatic index values for the population north of Torre Suda was observed in February, March and April. Events of spawning were observed in spring, summer and autumn south of Torre Suda and in winter north of Torre Suda. In particular, spawning events were observed in medium-sized sea urchin (diameter 36–50 mm) with a high Repletion index value. [ABSTRACT FROM AUTHOR]

Invasive habitat-forming species cause large changes to the abiotic environment, which may lead to lethal and sublethal effects on native fauna. In this study, we tested whether morphological anti-predator traits of an infaunal bivalve, Anadara trapezia, differed between areas invaded by the habitat-forming seaweed Caulerpa taxifolia and uninvaded habitats in estuaries in New South Wales, Australia. Caulerpa changes the abiotic environment in ways that may affect traits of native species. In particular, there is lower water flow, lower dissolved oxygen in the water and sediments are more silty and anoxic than in unvegetated habitat. To test our hypotheses, we collected Anadara from Caulerpa and uninvaded habitats and measured shell thickness, shell strength and resistance to opening of valves. We found that all three traits were reduced in Anadara from Caulerpa habitat compared with Anadara from uninvaded habitats. These findings are consistent with the idea that trait modifications in native fauna in response to invasive habitat-forming species can potentially increase susceptibility to predation. Invasive habitat-forming species modify important environmental factors with major consequences for associated fauna. We examined how the invasive habitat-forming seaweed Caulerpa taxifolia affects anti-predator traits of a native bivalve and found that bivalves in Caulerpa habitat have thinner, weaker shells and low resistance to opening of their valves. These trait modifications are likely to increase their susceptibility to predation. [ABSTRACT FROM AUTHOR]

Little research has been done in optimizing the nitrogenous fraction of the fish diets in order to minimize welfare problems. The purpose of this review is to give an overview on how amino acid (AA) metabolism may be affected when fish are under stress and the possible effects on fish welfare when sub-optimal dietary nitrogen formulations are used to feed fish. In addition, it intends to evaluate the current possibilities, and future prospects, of using improved dietary nitrogen formulations to help fish coping with predictable stressful periods. Both metabolomic and genomic evidence show that stressful husbandry conditions affect AA metabolism in fish and may bring an increase in the requirement of indispensable AA. Supplementation in arginine and leucine, but also eventually in lysine, methionine, threonine and glutamine, may have an important role in enhancing the innate immune system. Tryptophan, as precursor for serotonin, modulates aggressive behaviour and feed intake in fish. Bioactive peptides may bring important advances in immunocompetence, disease control and other aspects of welfare of cultured fish. Fishmeal replacement may reduce immune competence, and the full nutritional potential of plant-protein ingredients is attained only after the removal or inactivation of some antinutritional factors. This review shows that AA metabolism is affected when fish are under stress, and this together with sub-optimal dietary nitrogen formulations may affect fish welfare. Furthermore, improved dietary nitrogen formulations may help fish coping with predictable stressful events. [ABSTRACT FROM AUTHOR]

The xylA gene from a marine bacterium, Vibrio sp. strain XY-214, encoding D-xylose isomerase (XylA) was cloned and expressed in Escherichia coli. The xylA gene consisted of 1,320-bp nucleotides encoding a protein of 439 amino acids with a predicted molecular weight of 49,264. XylA was classified into group II xylose isomerases. The native XylA was estimated to be a homotetramer with a molecular mass of 190 kDa. The purified recombinant XylA exhibited maximal activity at 60°C and pH 7.5. Its apparent Km values for D-xylose and D-glucose were 7.93 and 187 mM, respectively. Furthermore, we carried out Dxylulose production from β-1,3-xylan, a major cell wall polysaccharide component of the killer alga Caulerpa taxifolia. The synergistic action of β-1,3-xylanase (TxyA) and β-1,3-xylosidase (XloA) from Vibrio sp. strain XY-214 enabled efficient saccharification of β-1,3-xylan to D-xylose. D-Xylose was then converted to D-xylulose by using XylA from the strain XY-214. The conversion rate of D-xylose to D-xylulose by XylA was found to be approximately 40% in the presence of 4 mM sodium tetraborate after 2 h of incubation. These results demonstrated that TxyA, XloA, and XylA from Vibrio sp. strain XY-214 are useful tools for D-xylulose production from β-1,3-xylan. Because D-xylulose can be used as a source for ethanol fermentation by yeast Saccharomyces cerevisiae, the present study will provide a basis for ethanol production from β-1,3-xylan. [ABSTRACT FROM AUTHOR]

Habitat change of coastal wetlands caused by natural and anthropogenic factors is an important issue facing China. Large areas of coastal habitat are disappearing, and those remaining become vulnerable to anthropogenic impacts from industry, agriculture, aquaculture, urban development, and domestic waste. A question is whether the change of habitat area has an influence on boundary adjustments of natural reserves. The study reported in this paper applied remotesensing images, and environmental and socioeconomic data to analyse the change of land use and land cover and habitat quality in an estuarine area and to identify the driving forces for these changes from 1988 to 2008. The results show that land use has changed significantly over this period. Cultivated lands occupying total area 35.96% decreased from 36,879.0 ha to 35,313.7 ha from 1988 to 1999. The area of settlements expanded from 11,305.1 ha in 1988 to 16,661.3 ha in 1999 and further to 23,258.6 ha in 2008. The areas of settlement, saltwater bodies, and unused land increased by 47.38%, 33.51%, and 16.66%, respectively, from 1988 to 1999. These trends continued from 1999 to 2008. The total average biomass in 2003 was far below the biomass of the same region in 1983 and the biological density also decreased sharply. The gross domestic product and population of the Dagang District grew continuously from 1993 to 2006 and was the main driving force of habitat change. The habitat quality of coastal wetlands is associated with natural reserve boundaries, which should be modified according to the actual protection status. The suggestion of boundary adjustment has also assisted the enhancement of habitat quality of coastal wetlands. This research emphasises the improvement of coastal environments through implementation of boundary adjustments. [ABSTRACT FROM AUTHOR]

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European sea bass and gilthead sea bream are two major marine finfish species reared in the Mediterranean region. Feeds for these species have high protein levels, usually supplied by fish meal. Research on alternatives to fish meal is mainly focused on plant protein feedstuffs, which are generally high in carbohydrates. Therefore, understanding the potential use of dietary carbohydrate is crucial for better utilization of such feedstuffs in the diets for these species. Factors that affect carbohydrate digestibility, metabolic utilization, as well as regulation of glucose metabolism are discussed. Data show that to ensure high digestibility, growth, and feed utilization, diets for these species should include around 20% digestible carbohydrate. Digestibility of native starch is high (above 70%) in both species, and it is further improved by processing starches (above 90%). Regarding carbohydrate complexity, it appears that European sea bass perform better with starch than glucose, while the opposite is true for gilthead sea bream. An enhancement in the activity of key enzymes of the glycolytic pathway and an increase of liver glycogen content is generally observed in the two species after feeding carbohydrates. An inverse regulation of the gluconeogenic enzyme activities with dietary carbohydrate intake is not observed in either species. [ABSTRACT FROM AUTHOR]

Background: Human parvovirus B19 (B19) virus is a newly recognized agent for transfusion transmitted diseases. Beta-thalassemia major patients receive a hypertransfusion regimen, hence, are prone to acquire B19 infection; moreover, B19 escapes viral inactivation methods and donor units are not tested for B19, but there are just a couple of studies globally and none from the Asian continent. Hence, a study was designed to find the frequency of B19 infection and its transmission in multitransfused thalassemia patients. Materials and Methods: Ninety multitransfused beta-thalassemia major (thalassemia) patients, 32 controls (age, sex matched) without any history of transfusion were enrolled. Besides the donor units were tested in B19 un-infected patients. B19 specific IgG and IgM antibodies in the sera were analyzed by ELISA (in-house), using B19 VPI and VP2 recombinant and purified antigens; additionally HBsAg and anti-HIV and anti- HCV antibodies were tested for coexisting infections. Results: Seventy-three (81%) thalassemia patients tested positive for anti-B19 IgG antibodies as compared to seven (21%) in the controls group (P < 0.01), while anti-B19 IgM antibodies were detected in 37 (41.1%) compared to two (6.2%) in the controls (P < 0.01). Mean age of the thalassemia patient was eight years (range 2 - 18 years) and B19 infection was highest in the six-to-ten year range. Seropositivity increased with the number of transfusions. Two of the four HBsAg positive and five of the seven anti-HCV IgM antibody-positive patients also had anti-B19 IgM. After a six-month follow-up, four (25%) of the 16 seronegative patients seroconverted and anti-B19 IgM antibodies were detected in their donor units. Conclusions: Most of multitransfused thalassemics were B19 seropositive or had anti-B19 IgM; in the remaining uninfected group, B19 got transmitted through infected / IgM-positive donor units. [ABSTRACT FROM AUTHOR]

We tested the utility of IKONOS satellite imagery to map seagrass distribution and biomass in a 4.1 km2 area around Chumbe Island, Zanzibar, Tanzania. Considered to be a challenging environment to map, this area is characterized by a diverse mix of inter- and subtidal habitat types. Our mapped distribution of seagrasses corresponded well to field data, although the total seagrass area was underestimated due to spectral confusion and misclassification of areas with sparse seagrass patches as sparse coral and algae-covered limestone rock. Seagrass biomass was also accurately estimated (r2 = 0.83), except in areas with Thalassodendron ciliatum (r2 = 0.57), as the stems of T. ciliatum change the relationship between light interception and biomass from that of other species in the area. We recommend the use of remote sensing over field-based methods for seagrass mapping because of the comprehensive coverage, high accuracy and ability to estimate biomass. The results obtained with IKONOS imagery in our complex study area are encouraging, and support the use of this data source for seagrass mapping in similar areas. [ABSTRACT FROM AUTHOR]

The influence of soybean meal (SBM) on the growth and feed utilization of juvenile sutchi catfish ( Pangasianodon hypophthalmus, Sauvage, 1878) was investigated. Eight isonitrogenous (300 g kg CP) and isoenergetic (18 MJ kg) diets were formulated incorporating Argentine SBM to replace fish meal at 0, 150, 300, 450, 600, 750, 900 and 1000 g kg dietary protein. Each diet was fed to three replicate groups of fish with an initial weight 6.0-6.2 g for twelve weeks. Growth performance decreased, and feed utilization was worsened with the increase in SBM inclusion in the diets. Final weight and relative growth rate (RGR) of fish fed control diet (0 SBM) were significantly higher than those fed test diets ( P < 0.05). However, there were no significant differences in the final weight and RGR between the fish fed on 15 SBM, 30 SBM, 45 SBM and 60 SBM diets. Specific growth rate of fish fed 0 SBM, 15 SBM, 30 SBM and 45 SBM diets was significantly higher than those fed other diets. Feed conversion ratio of fish fed 0 SBM, 15 SBM, 30 SBM, 45 SBM and 60 SBM diets was significantly lower than those fed other diets ( P < 0.05). The dry matter and protein digestibility were lesser in all the diets in comparison with the control diet. Hepatosomatic index and viscerosomatic index increased with increasing SBM in diet. This present trial indicated that fish meal can be replaced by SBM in the diet of juvenile sutchi catfish only up to 45% of fish meal protein without any adverse effect on growth, feed utilization and body composition. [ABSTRACT FROM AUTHOR]

Neogoniolithon brassica-florida (encrusting rhodobionta) is generally reported as a veneering coral community along the wave-beaten rocky coast of the Mediterranean Sea. Its presence in the hyperhaline lagoon of Bahiret el Bibane, situated in SE Tunisia, takes on particular importance because of its extension. It constitutes a reef formation 14 km long developing on both sides of the sea inlet. The building of this ''natural monument'' seems to be the result of an evolutionary series. The aim of this study was to investigate the current status of this reef, comparing it to 30 years ago. The current extension of the Neogoniolithon brassica-florida reef appears to be much reduced from that reported 30 years ago, indicating a regression of 26%. Four different phases leading to the reef building were also identified. [ABSTRACT FROM AUTHOR]

To be able to study nutrient requirement and utilization in any species, a diet supporting normal feed intake and growth equally well as a traditional fish meal-based diet is needed. Additionally the formulation of the diet should allow low levels of the nutrient under study. When studying the amino acid metabolism and requirements, one cannot rely on the fish meal-based diets as fish meal are nicely balanced according to requirements. Therefore the current study aimed to develop a plant protein-based diet (with low fish meal inclusion) to be used in the nutritional studies of Senegalese sole juveniles supporting feed intake and growth close to that obtained in a fish meal-based control feed. Two experiments were conducted to evaluate whether Senegalese sole juveniles would accept and utilize diets containing high plant protein inclusion. For testing the acceptance of high plant protein inclusion, two diets were formulated: a reference diet that contained fish meal as the main protein source (450 g kg−1 dry matter) whereas in the test diet, fish meal was substituted by a mixture of plant ingredients (soybean meal, corn and wheat gluten) withl-lysine supplementation. In order to improve the palatability, 50 g kg−1 squid meal was added to both diets. The indispensable amino acids (IAA) profile of the test diet was made similar to the control diet by adding crystalline amino acids. Further, automatic feeders were used to improve the feed intake. Fish (24 g initial body weight) were fed the diets for a period of 4 weeks. As fish accepted both diets equally well, a second study was undertaken to test the growth performance. Fish (6 g initial BW) were fed the diets for a period of 12 weeks. The use of automatic feeders to deliver the feed and the addition of both squid and balancing the indispensable amino acids resulted in growth performance and accretion not differing from the fish meal fed control. It can be concluded that juvenile Senegalese sole are able to grow and utilize high plant-protein diets when both diet composition and feeding regime are adequate for this species. [ABSTRACT FROM AUTHOR]

The Ligurian Sea is a deep basin in the northernmost sector of the western Mediterranean which shows peculiar hydrodynamic and meteo-oceanographic features. The coasts of the Ligurian Sea are among the most urbanised and industrialised along the Italian coastline: the main causes of disturbance being littoral urban development and harbour activities, the building of littoral rail- and highways, and the presence of several polluted discharges. This review, by evaluating the huge scientific output published in the last three decades, describes and discusses the most important geological, hydrological and biological characteristics of the Ligurian Sea. We show that this regional sea has largely been investigated in terms of its geological and structural evolution, as well as in terms of the sedimentation dynamics of the littoral and deep bottoms, with particular attention to the sedimentation balance of the beaches and their erosive processes. We report that the prevalent hydrodynamic and meteo-oceanographic conditions favour a continuous exchange of coastal water masses, and that the seasonal and interannual dynamics of water masses can effects the local climate, with direct and indirect consequences on fish and benthic communities documented in the last decade. We stress that although recent studies offer good knowledge of the distribution of coastal benthic communities, only scant information is available for the whole continental shelf, the submarine canyons and the rocky bathyal bottoms. Our meta-analysis reveals that significant fishing activities are monitored, but also that certain sectors of the biological resource are suffering, and suggests the set up of appropriate management measures. The Ligurian Sea hosts a number of Marine Protected Areas (MPAs) of high relevance, while the institution of the Whale Sanctuary completes the protection policy of the Regione Liguria. Our meta-analysis points out the need for long-term studies, based primarily on the analysis of those areas of the Ligurian Sea that have been little investigated to date. Finally, only properly addressed studies, using experimental approaches and along appropriate spatial and temporal scales, might allow us to understand the functioning of the Ligurian marine ecosystems, evaluate their health conditions and the dynamics of the main variables that affect the distribution of the single species (including species of high economic value) and benthic communities. [ABSTRACT FROM AUTHOR]

Abstract  Two hundred and forty adult and sub-adult Paracentrotus lividus were divided into two major groups (adults, sub-adults) based on their diameter differences (above or below 40 mm) and allocated to baskets suspended from the walkways of finfish cages, in South Evoikos Gulf, Central Greece. Each group were fed a commercial finfish diet, while their respective controls remained unfed during the whole duration of the experiment. Total weight and gonad weight of all treatment groups increased while the respective weights of the control groups decreased by the end of the experiment. In addition, gonad indices of the treatment groups increased by the end of the experiment, except for the sub-adult groups. No mortalities were observed in the treatment groups, while the low mortalities in the control groups (1–1.5%) can be attributed to the nutrient status of the surrounding waters and the increased plankton populations and sedentary organisms. It has therefore been shown that fish/sea urchin polyculture in Greece can be low risk and beneficial for the producer system, as long as prevailing water quality and environmental aquaculture standards are kept. [ABSTRACT FROM AUTHOR]

A decrease in seagrass cover and a commensurate increase in Caulerpa taxifolia distribution in Moreton Bay have prompted concern for the impact that habitat change may have on faunal communities. Therefore, it is important to understand the patterns of habitat use. We examined habitat selection of three common seagrass species: double-ended pipefish ( Syngnathoides biaculeatus), eastern trumpeter ( Pelates quadrilineatus), and fan-bellied leatherjacket ( Monacanthus chinensis) using a mesocosm experiment. Fish were given three possible habitat pairings (1) seagrass and C. taxifolia, (2) seagrass and unvegetated, and (3) C. taxifolia and unvegetated. Observation trials were conducted during the day and night over two days. In all trials, fish preferred vegetated habitat (seagrass or C. taxifolia) over unvegetated habitat (sand). In seagrass and C. taxifolia trials, all species preferred seagrass significantly over C. taxifolia. Habitat use patterns did not differ between day and night trials. Caulerpa taxifolia provides a valuable structured habitat in the absence of seagrass; however, it is unclear if C. taxifolia meadows provide other resource benefits to fishes beyond that of shelter. [ABSTRACT FROM AUTHOR]

Although a broad variety of classes of bioactive compounds have already been isolated from seaweeds of the genus Dictyota, most different species are still chemically and biologically unexplored. Dictyota species are well-known brown seaweeds belonging to the Dictyotaceae (Phaeophyta). The phytochemical composition within the genus Dictyota has recently received considerable interest, and a vast array of components, including diterpenes, sesquiterepenes, sterols, amino acids, as well as saturated and polyunsaturated fatty acids, have been characterized. The contribution of these valued metabolites to the biological potential, which includes anti-proliferative, anti-microbial, antiviral, antioxidant, anti-inflammatory, and anti-hyperpigmentation activities, of the genus Dictyota has also been explored. Therefore, this is the most comprehensive review, focusing on the published literature relevant to the chemically and pharmacologically diverse biopharmaceuticals isolated from different species of the genus Dictyota during the period from 1976 to now. [ABSTRACT FROM AUTHOR]

Seagrass distribution is a very important index for costal management and protection. Seagrass distribution changes can be used as indexes to analyze the reasons for the changes. In this paper, in situ hyperspectral observation and satellite images of QuickBird, CBERS (China Brazil Earth Resources Satellite data) and Landsat data were used to retrieve bio-optical models and seagrass (Enhalus acoroides, Thalassia hemperichii) distribution in Xincun Bay, Hainan province, and seagrass distribution changes from 1991 to 2006 were analyzed. Hyperspectral results showed that the spectral bands at 555, 635, 650 and 675 nm are sensitive to leaf area index (LAI). Seagrass detection with QuickBird was more accurate than that with Landsat TM and CBERS; five classes could be classified clearly and used as correction for seagrass remote sensing data from Landsat TM and CBERS. In order to better describe seagrass distribution changes, the seagrass distribution area was divided as three regions: region A connected with region B in 1991, however it separated in 1999 and was wholly separated in 2001; seagrass in region C shrank gradually and could not be detected in 2006. Analysis of the reasons for seagrass reduction indicated it was mainly affected by aquaculture and typhoons and in recent years, by land use changes. [ABSTRACT FROM AUTHOR]

Abstract  The study evaluated different macroalgal invasions in the main Mediterranean coastal habitats on hard bottom. Biodiversity, species composition and structure of macroalgal assemblages were compared among non-invaded areas and areas invaded by the Chlorophyta Caulerpa racemosa var. cylindracea and by the turf-forming Rhodophyta Womersleyella setacea in three different habitats: shallow rocky bottom, deep rocky bottom and dead matte of the seagrass Posidonia oceanica. Results showed that alien macroalgae constituted a relevant component of benthic assemblages in invaded areas of the Mediterranean Sea. Assemblages invaded by Womersleyella setacea and Caulerpa racemosa showed lower values of diversity and large differences in the structure and species composition related to non-nvaded assemblages. The species that mostly suffered from invasion were erect species reproducing sexually; moreover, the dominance of W. setacea led to low abundance of native filamentous algae, while C. racemosa colonization seemed particularly threatening for encrusting algae. All the studied habitats appeared highly invasible by alien macroalgae, even if W. setacea appeared more invasive in deeper habitats, while colonization of C. racemosa seemed more serious in shallower habitats; the dead matte of P. oceanica represented a suitable substrate for the spread of both species. Differences among assemblages in different habitats were reduced in invaded areas. [ABSTRACT FROM AUTHOR]

The underexplored biodiversity of seaweeds has recently drawn great attention from researchers to find the bioactive compounds that might contribute to the growth of the blue economy. In this study, we aimed to explore the effect of seasonal growth (from May to September) on the in vitro antioxidant (FRAP, DPPH, and ORAC) and antimicrobial effects (MIC and MBC) of Cystoseira compressa collected in the Central Adriatic Sea. Algal compounds were analyzed by UPLC-PDA-ESI-QTOF, and TPC and TTC were determined. Fatty acids, among which oleic acid, palmitoleic acid, and palmitic acid were the dominant compounds in samples. The highest TPC, TTC and FRAP were obtained for June extract, 83.4 ± 4.0 mg GAE/g, 8.8 ± 0.8 mg CE/g and 2.7 ± 0.1 mM TE, respectively. The highest ORAC value of 72.1 ± 1.2 µM TE was obtained for the August samples, and all samples showed extremely high free radical scavenging activity and DPPH inhibition (>80%). The MIC and MBC results showed the best antibacterial activity for the June, July and August samples, when sea temperature was the highest, against Listeria monocytogenes, Staphylococcus aureus, and Salmonella enteritidis. The results show C. compressa as a potential species for the industrial production of nutraceuticals or functional food ingredients. [ABSTRACT FROM AUTHOR]

Ericaria crinita and Ericaria amentacea from the Adriatic Sea (Croatia) were investigated with respect to the presence of less-polar compounds for the first time after fractionation by solid-phase extraction (SPE). The composition of less-polar fractions of freeze-dried E. crinita (FdEc) and E. amentacea (FdEa) were analyzed by high-performance liquid chromatography–high-resolution mass spectrometry with electrospray ionization (UHPLC-ESI-HRMS). The major identified compounds were: amides of higher aliphatic acids (palmitoleamide, linoleamide, palmitamide, oleamide and erucamide) and related compounds, carotenoid (fucoxanthin), chlorophyll derivatives (pheophytin a and b and their derivatives) and higher terpenes (loliolide, isoamijiol with its oxidation product), β-stigmasterol and (3β,6α)-14-methylergosta-8,24(28)-diene-3,6-diol). The toxic effects observed on the less-polar fractions obtained from Ericaria species on zebrafish Danio rerio embryos could be associated with the high abundance of all five detected amides. The antioxidant activity of the fractions was evaluated by means of five independent assays, including the reduction of the radical cation (ABTS), the oxygen radical absorbance capacity (ORAC), ferric-reducing antioxidant power (FRAP), the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay and the Folin–Ciocalteu method. A higher antioxidant activity of E. amentacea in comparison to that of the E. crinita fractions was found with IC50 concentrations of 0.072 and 1.177 mg/mL, respectively. The correlation between the activity and the chemical composition revealed that the synergistic effect of different compounds impacted their antioxidant response. [ABSTRACT FROM AUTHOR]

Despite well-documented negative impacts of invasive species on native biota, evidence for the facilitation of native organisms, particularly by habitat-forming invasive species, is increasing. However, most of these studies are conducted at the population or community level, and we know little about the individual fitness consequences of recruitment to habitat-forming invasive species and, consequently, whether recruitment to these habitats is adaptive. We determined the consequences of recruitment to the invasive green alga Caulerpa taxifolia on the native soft-sediment bivalve Anadara trapezia and nearby unvegetated sediment. Initially, we documented the growth and survivorship of A. trapezia following a natural recruitment event, to which recruitment to C. taxifolia was very high. After 12 months, few clams remained in either habitat, and those that remained showed little growth. Experimental manipulations of recruits demonstrated that all performance measures (survivorship, growth and condition) were significantly reduced in C. taxifolia sediments compared to unvegetated sediments. Exploration of potential mechanisms responsible for the reduced performance in C. taxifolia sediments showed that water flow and water column dissolved oxygen (DO) were significantly reduced under the canopy of C. taxifolia and that sediment anoxia was significantly higher and sediment sulphides greater in C. taxifolia sediments. However, phytoplankton abundance (an indicator of food supply) was significantly higher in C. taxifolia sediments than in unvegetated ones. Our results demonstrate that recruitment of native species to habitat-forming invasive species can reduce growth, condition and survivorship and that studies conducted at the community level may lead to erroneous conclusions about the impacts of invaders and should include studies on life-history traits, particularly juveniles. [ABSTRACT FROM AUTHOR]

Macroalgal invasions in coastal areas have been a growing concern during the past decade. The present study aimed to assess the role of hull fouling on recreational yachts as a vector for macroalgal introductions. Questionnaire and hull surveys were carried out in marinas in France and Spain. The questionnaires revealed that the majority of yacht owners are aware of seaweed introductions, usually undertake short range journeys, dry dock their boat at least once a year, and use antifouling paints. The hull survey showed that many in-service yachts were completely free of macroalgae. When present, fouling assemblages consisted mainly of one to two macroalgal species. The most commonly found species was the tolerant green seaweed Ulva flexuosa. Most of the other species found are also cosmopolitan and opportunistic. A few nonnative and potentially invasive Ceramiales (Rhodophyta) were found occasionally on in-service yachts. On the basis of the information gathered during interviews of yacht owners in the surveyed area, these occurrences are likely to be uncommon. However they can pose a significant risk of primary or secondary introductions of alien macroalgal species, especially in the light of the increase in yachting activities. With large numbers of recreational yachts and relatively rare occurrences of nonnative species on hulls, comprehensive screening programs do not seem justified or practical. The risks of transferring nonnative species may, however, be minimized by encouraging the behaviors that prevent fouling on hulls and by taking action against neglected boats before they can act as vectors. [ABSTRACT FROM AUTHOR]

Abstract  There is worldwide concern about the aquarium strain of the green alga Caulerpa taxifolia (Vahl) C. Agardh that was introduced to the Mediterranean Sea in 1984. Since that time, it has flourished and now covers thousands of hectares of near-shore waters. More recently, aquarium strains of C. taxifolia invaded southern California and Australian waters. Our goal was to evaluate potential invasion of C. taxifolia to Florida’s coastal waters. We looked for evidence of C. taxifolia—aquarium strain, as well as the present distribution of all species of Caulerpa, in Florida’s near-shore waters. We surveyed 24 areas in six zones along the Floridian coastline, and evaluated the association of potential indicators for the presence of Caulerpa. Latitude, presence of seagrass beds, human population density, and proximity to marinas were the four variables simultaneously considered. Caulerpa taxifolia—aquarium strain was not found at any of our survey locations. However, 14 species of Caulerpa were found at 31 of the 132 sites visited. Percent correct for our model was 61.5% for presence and 98.1% for absence. There was a positive correlation between Caulerpa spp. and seagrass beds and proximity to marinas. There was a negative correlation with latitude and human population density. The parameters in the logistic regression model assessing the association of Caulerpa occurrence with the measured variables were then used to predict current and future probabilities of Caulerpa spp. presence throughout the state. This prediction model will allow resource managers to focus their efforts in future surveys. [ABSTRACT FROM AUTHOR]

Surgery in infants and young children with haemophilia, when preceded by accurate diagnosis and accompanied by safe and effective factor prophylaxis, is not associated with a significant risk of haemorrhage. Haemophilic newborns undergoing circumcision or major surgery prior to diagnosis and in the absence of appropriate haemostatic prophylaxis remain as a concern. Inhibitor development has replaced haemorrhage as the major surgical complication in the developed world, largely because of the intensity of treatment used to secure haemostasis. For that reason only, essential surgery should be performed. Intracranial haemorrhage (ICH) during the neonatal period affects 3.5–4.0% of all haemophilia boys in countries with a good standard of health care, which is considerably (40–80 times) higher than expected in the normal population. Because of the high frequency of sporadic cases, ICH in the neonatal period can only be partially prevented by improved carrier diagnosis and counselling. Infections and thrombosis are the major serious complications of central venous lines. Large differences are seen in the frequency of these complications, the most plausible explanations are probably related to the protocol used for device care, the quality of education and the compliance of the users, an issue addressed in an on-going study. [ABSTRACT FROM AUTHOR]

Pederson, H. G., and Johnson, C. R. 2008. Growth and age structure of sea urchins (Heliocidaris erythrogramma) in complex barrens and native macroalgal beds in eastern Tasmania. – ICES Journal of Marine Science, 65: 1–11.The formation of small-scale barrens of sea urchins on the east coast of Tasmania allows for direct comparison of the growth rates and age structures of sea urchin populations in barrens and habitats dominated by native macroalgae. However, such barrens are atypical of any previously described in temperate regions worldwide mainly because of the establishment and seasonal colonization by the introduced macroalga Undaria pinnatifida. Growth models were fitted to sea urchin (Heliocidaris erythrogramma) data, based on tag-recapture information from two distinct community types, a native macroalgal bed and a sea urchin barren colonized by U. pinnatifida. Despite the distinct contrast in habitats, size-at-age relationships and age frequency distributions were not significantly different between the two populations. However, the relationship between jaw length and test diameters was significantly different between populations, sea urchins in barrens possessing larger jaws relative to conspecifics of similar test diameter in native macroalgal habitats. It is proposed that the growth of sea urchins on barrens is not adversely affected by the loss of native macroalgae in the presence of U. pinnatifida. However, sea urchins display a level of resource limitation in barrens because of differences in the relationships of sea urchin morphometrics. [ABSTRACT FROM PUBLISHER]

Tracking macroalgal invasions relies on a variety of approaches and techniques, including random sampling, active tracking near sources of introduction, and identification of alien species and their vectors of introduction using both classical means (based on taxonomical and biogeographical knowledge) and molecular tools. To identify the invaded ecosystems, and to describe the rate of spread and invasion dynamics, other approaches must be used, including mapping techniques and public awareness campaigns. In these endeavours, standardisation of geographical and density data is important. The tracking of alien species before eradication or control measures are instigated requires special cartographic techniques. This paper provides a general overview of these different approaches and the specific strategies adapted to the biological and ecological characteristics of particular species. [ABSTRACT FROM AUTHOR]

Growth characteristics of native and invasive Caulerpa taxifolia from coastal eastern Australia were compared in warm (22–25°C) and cool (15–18°C) water in two laboratory experiments. Measurements of biomass, stolon length, mean frond length and numbers of fronds and stolon meristems, demonstrated that the growth of native and invasive C. taxifolia in warm water was up to ten times greater than in cool water. Growth rates differed substantially among locations over 9 weeks, but for most variables, the growth of native C. taxifolia was greater than the growth of invasive C. taxifolia in warm water. In cool water, there was little difference in growth of invasive versus native C. taxifolia. The morphology of C. taxifolia changed considerably in response to temperature, such that native and invasive samples that were morphologically distinct at the start of the experiment became indistinguishable after 69 days in warm water. We concluded there was little evidence that the C. taxifolia which recently invaded temperate estuaries in New South Wales could spread faster in cool water than could native C. taxifolia from Queensland. Native tropical C. taxifolia appears tolerant of a wide range of environmental conditions and seems capable of surviving and becoming invasive in temperate estuaries. [ABSTRACT FROM AUTHOR]

Pre-spawning reproductive biology and population structure of the sea cucumber Isostichopus fuscus were analysed at the Caamaño Island, Galápagos Islands, Ecuador on a monthly basis between January 1995 and June 1996. An average of 25 individuals of all sizes were collected each month. Using microscopic characteristics of the gonads three gonadal stages were described: (1) immature; (2) mature, and (3) spent. Mature individuals showed statistically different morphometric characteristics. I. fuscus was continuously sexually mature throughout the year independent of changes in sea water temperature. Mean oocyte diameter indicated planktotrophic larval development. Mean fecundity for this species was 567,884 (±95,528 SE) eggs per gonad. Size at first maturity was between 161.0 and 170.9 g drained weight and the smallest individual found with mature gonads had a drained weight between 121.0 and 130.9 g. The population sampled ranged between 13 and 31 cm (81.0–400.0 g) with less than 10% of the population of individuals ≥25 cm (≥300.0 g). No juveniles were recorded. [ABSTRACT FROM AUTHOR]

The reproductive strategies of the sea urchin, Paracentrotus lividus, were studied in the Bay of Tunis. Samples were collected monthly, from September 1993 to August 1995, in two sites which differ in their marine vegetation and their exposure to wave action. Histological examination demonstrated a cycle of gametogenesis with six reproductive stages and a main breeding period occurring between April and June. Gonad indices varied between sites and years, the sheltered site presenting a higher investment in reproduction.This difference was essentially induced by the largest sea urchins (above 40 mm in diameter). Repletion indices showed a clear pattern without difference between sites and years. The sea urchin increase in feeding activity was controlled by the need to allocate nutrient to the gonad during the mature stage. But the gonad investment was not correlated with the intensity of food intake. Hydrodynamic conditions might play a key role in diverting energy to the maintenance in an exposed environment at the expense of reproduction. [ABSTRACT FROM PUBLISHER]

Three taxa of Caulerpa racemosa that differ morphologically and genetically have been reported in the Mediterranean Sea. The ‘invasive variety’ was recorded for the first time in the early 1990s in Libya. In less than 10 years, it was found in almost all parts of the Mediterranean. The first record of C. racemosa in the Croatian part of the Adriatic Sea was in 2000 and as many as 35 different localities were established by the end of 2004. In terms of morphology, the specimens from the Adriatic Sea resemble the ‘invasive variety’. To confirm this, we analysed populations from two different localities (the island of Mljet and the peninsula of Pelješac) using the ITS1-5.8S-ITS2 region of 18S-5.8S-26S rDNA unit as a molecular marker. The ITS1-5.8S-ITS2 region from nine individual plants was amplified by PCR, cloned in a pCR 2.1 vector and sequenced. Phylogenetic comparison of sequences from specimens found in the Adriatic Sea with specimens of the same and similar taxa, found both inside and outside the Mediterranean, provided genetic evidence that C. racemosa populating the Adriatic Sea corresponds to the Mediterranean C. racemosa var. cylindracea (Sonder) Verlaque, Huisman & Boudouresque, i.e. to the ‘invasive variety’. [ABSTRACT FROM AUTHOR]

Baseline genotypes were established for 256 individuals of Caulerpa collected from 27 field locations in Florida (including the Keys), the Bahamas, US Virgin Islands, and Honduras, nearly doubling the number of available GenBank sequences. On the basis of sequences from the nuclear rDNA-ITS 1+2 and the chloroplast tufA regions, the phylogeny of Caulerpa was reassessed and the presence of invasive strains was determined. Surveys in central Florida and southern California of >100 saltwater aquarium shops and 90 internet sites revealed that >50% sold Caulerpa. Of the 14 Caulerpa species encountered, Caulerpa racemosa was the most common, followed by Caulerpa sertularioides, Caulerpa prolifera, Caulerpa mexicana, and Caulerpa serrulata. None of the >180 field-collected individuals (representing 13 species) was the invasive strain of Caulerpa taxifolia or C. racemosa. With one exception (a sample of C. racemosa from a shop in southern California belonged to the invasive Clade III strain), no invasive strains were found in saltwater aquarium stores in Florida or on any of the internet sites. Although these results are encouraging, we recommend a ban on the sale of all Caulerpa species (including “live rock”) because: morphological identification of Caulerpa species is unreliable (>12% misidentification rate) and invasive strains can only be identified by their aligned DNA sequences, and because the potential capacity for invasive behavior in other Caulerpa species is far from clear. The addition of the Florida region to the genetic data base for Caulerpa provides a valuable proactive resource for invasion biologists as well as researchers interested in the evolution and speciation of Caulerpa. [ABSTRACT FROM AUTHOR]

Abstract  This study compared algal palatability and chemical defenses from subtropical green algae that may use different types of defense systems that deter feeding by the rock-boring sea urchin Echinometra lucunter. The potential defense systems present include (1) the terpenoid caulerpenyne and its activated products from Caulerpa spp., and (2) dimethylsulfoniopropionate (DMSP)-related defenses in Ulva spp. Secondary metabolites from these chemical groups have been shown to deter feeding by various marine herbivores, including tropical and temperate sea urchins. Live algal multiple-choice feeding assays and assays incorporating algal extracts or isolated metabolites into an artificial diet were conducted. Several green algae, including Ulva lactuca, Caulerpa prolifera, and Cladophora sp., were unpalatable. Nonpolar extracts from U. lactuca deterred feeding, whereas nonpolar extracts from C. prolifera had no effect on feeding. Polar extracts from both species stimulated feeding. Caulerpenyne deterred feeding at approximately 4% dry mass; however, dimethyl sulfide and acrylic acid had no effect at natural and elevated concentrations. E. lucunter is more tolerant than other sea urchins to DMSP-related defenses and less tolerant to caulerpenyne than many reef fish. Understanding the chemical defenses of the algae tested in this study is important because they, and related species, frequently are invasive or form blooms, and can significantly modify marine ecosystems. [ABSTRACT FROM AUTHOR]

Abstract  High levels of protein in fish feeds result in higher costs and nitrogen waste. Therefore, studies focused on protein substitution by alternative energy sources are necessary. Here we examine whether the protein:carbohydrate ratio in extruded diets affects protein-turnover parameters and the main tissue components in brown trout. Juvenile fish were adapted to two extruded diets: one higher in protein and lower in carbohydrate, C: 45/28 and the other higher in carbohydrate and lower in protein, HC: 37/40. Gross energy was 19 MJ  kg−1 DM in both diets. Protein and lipid digestibility were high and similar in both groups (≈90%), whereas total and carbohydrate digestibility and digestible energy were lower in the HC-fed group than in the C-fed group. Consequently, when fish were adapted to the diets, plasma levels of glucose and insulin differed between diets. HC-group presented higher plasma glucose levels and lower plasma insulin levels than C-group. Protein synthesis rates in white muscle, liver and whole body did not differ significantly between diets. In contrast, protein accretion rate of white muscle and whole body were significantly lower in the HC group, indicating an increase of protein degradation in these tissues and a decrease of synthesis retention efficiency. In spite of the daily protein intake of HC group was lower than C-group, the anabolic stimulation efficiency was increased by 34% in HC group. Protein and lipid contents in white muscle and liver were stable throughout the experiment. No hepatomegalia or increased fat deposition was observed in fish fed HC. Differences in specific growth rates (C: 0.88%; HC: 0.77%) were associated more with the lower protein consumption rate and the lower level of digestible energy in fish fed HC than with the higher dietary carbohydrate content of the diet. [ABSTRACT FROM AUTHOR]

The significance of marine algal invasion is undisputed in the global context; however, this topic has not received as much attention as it deserves. Although substantial evidence supports the fact of marine algal introduction and invasion, the underlying ecological principles need more attention to better explain such invasions. Marine algal invasions transcend national boundaries, so the problem must be considered an international problem. Commercial exploitation of invasive marine algae (and under this category we include deliberate introductions) should be undertaken, if at all, with great care and with a full understanding of all aspects of the biology and ecological consequences of the new exotic species. The aim of this article is to define algal invaders from a marine ecosystem standpoint and to discuss the different vectors, their dispersal patterns, and mechanisms of their dominance in their naturalized or introduced range. [ABSTRACT FROM AUTHOR]

Population modeling based on species’ demography makes it possible to predict the pace of an invasion and evaluate the likelihood of success of different control strategies. We modeled the initial (density-independent) rate of increase of Caulerpa taxifolia (Vahl) C. Agardh (aquarium strain), a green alga that has markedly altered marine communities where it has invaded in the Mediterranean Sea. Parameter values for patch growth (from stolon extension) and reproduction (by asexual fragmentation and reattachment) were gleaned from published studies. Only the most conservative model, invoking field growth rates and low levels of fragment reattachment (2.5 m−2 of existing patch each summer), closely matched observed increases (4–14 × annually). The most effective times for control (greatest reduction in rate of increase) were removal of established patches before summer and removal of fragments after summer. These times correspond to just before maximum growth and just after maximum reproduction, respectively. Only a combined strategy, incorporating 99% removal of all fragments and annual removal of 99% of established patches, was predicted to eliminate C. taxifolia entirely (λ < 1). This level of effort is only likely to be possible during the first few years of an invasion, arguing strongly for careful monitoring and rapid response to potential high-impact invaders. [ABSTRACT FROM AUTHOR]

Marine organisms produce a wide array of fascinating terpenoid structures distinguished by characteristic structural features. Certain structural classes, e.g. cembrane, chamigrene, amphilectane skeletons, and unusual functional groups such as isonitrile, isothiocyanate, isocyanate, dichloroimine and halogenated functionalities occur predominantly in marine metabolites. Especially striking is the frequent occurrence of sesterterpenes in marine organisms, and sponges must be considered as one of the prime sources of these C25 terpenoid compounds. In most cases however, these structural features are not strictly unique for marine natural products. The prominent biological activity of marine terpenes is evident in their ecological role in the marine environment, and makes them interesting as potential drugs. Several terpenoid compounds, e.g. eleutherobin, sarcodictyin, contignasterol derivatives, are in preclinical or clinical development. Despite the many structures known and their ecological and pharmacological importance, only a few biosynthetic studies on marine terpenoid compounds have been performed. [ABSTRACT FROM AUTHOR]

Several species of Kappaphycus were intentionally introduced into Kane’ohe Bay, Hawai’i in the 1970s. Subsequent research has demonstrated that these algae have spread rapidly throughout the bay and can be found in a variety of reef habitats overgrowing and killing corals. This study was conducted to (a) quantify Kappaphycus spp. abundance both spatially and temporally, and (b) investigate control options including manual removal and the use of biocontrol agents. Kappaphycus spp. distribution has increased in the bay over the period between surveys conducted in 1999 and 2002, with variation among reefs. The biomass of Kappaphycus spp. removed, and the amount of time required to manually remove them from the reef varied with habitat type, but in all cases amounted to at least 10 kg/m2 requiring almost 2 person-hours to clear 1 m2. Re-growth of the algae following their removal was rapid at most sites, likely due to the experimentally demonstrated ability of the algae to re-grow from minute attachment points and the low palatability of the algae to native herbivorous fishes. The native sea urchin, Tripneustes gratilla, reduced the biomass of Kappaphycus spp. in small experimental enclosures and may be a useful biocontrol agent. Because Kappaphycus spp. are still spreading in Kane’ohe Bay and can overgrow over 50% cover on some reefs, we recommend that rapid management action be taken to prevent further damage and spread to other Hawaiian coral reefs. [ABSTRACT FROM AUTHOR]

The tropical and subtropical marine green alga Caulerpa taxifolia has invaded several temperate regions throughout the world, including southeastern Australia. In this study, I examined how invasive C. taxifolia from temperate southeastern Australia differed from native C. taxifolia from subtropical Moreton Bay, Australia, in the traits proposed as being important to its invasion success: thallus size and density, levels of asexual reproduction (fragmentation) and total biomass. Against the prediction of a large size for invasive C. taxifolia, native populations from Moreton Bay had larger stolons and fronds than invasive populations. However, invasive populations consistently had much higher densities of stolons, fronds and fragmented fronds; and a greater biomass compared to native populations. Average densities at invasive sites exceeded 4,700 stolons and 9,000 fronds/m2and were as high as 27,000 stolons and 95,000 fronds/m2, whichare the highest reported for C. taxifolia anywhere. Average densities of fragmented fronds at invasive sites were as high as 6,000/m2and up to 45% of all stolons at invasive sites could be directly linked to asexual recruitment via fragmented fronds. Importantly, at invasive locations there was a strong association between asexual reproduction and abundance demonstrated by positive correlations between the density of fragmented fronds and total biomass. These findings are the first to describe quantitative differences between native and invasive C. taxifolia and to demonstrate a link between the high levels of asexual reproduction and high abundance in invasive populations. Although the causes and consequences of high levels of asexual reproduction remain to be explored, this study suggests that changes in demographic and life-history traits during the invasion by C. taxifolia into temperate habitats may contribute to its success there. [ABSTRACT FROM AUTHOR]

We sought to determine whether common intertidal and shallow subtidal zone grazers would consume extracts or fronds of three invasiveCaulerpaspp., all of which are now resident in southern New South Wales, Australia. We examined the responses of herbivorous fishes, echinoderms and molluscs toC.filiformis. A subset of these organisms was tested with extracts ofC.scalpelliformisandC.taxifolia. Polar (seawater) extracts ofC.filiformisdeterred a single herbivore,Aplysia sydneyensis, but confirmed that the biological activity reported from someCaulerpaspp. is not restricted to the lipophilic fractions. The large turbinidTurbo torquatuswas deterred by an ethanol extract ofC.filiformis, while the small congenerT.undulatusdemonstrated a significant preference for palatable agar discs containing ethanol extracts ofC.filiformis. However, whenT.undulatuswere offered a choice of fronds from five algal species in the laboratory, they readily consumedUlvaspp. andSargassumsp., showing the lowest preference forC.filiformis. Solvent extracts ofC.scalpelliformisandC.taxifoliadid not significantly deter any grazers. However, the overall trend was for reduced consumption of discs containing solvent extracts of these seaweeds. Indeed, for the large urchinCentrostephanus rodgersiiand in the fish trials these effects were very near significant (P<0.06). We conclude that common herbivores associated with hard substrata are highly unlikely to intercede in the spread or control of these invasive algae. [ABSTRACT FROM AUTHOR]

The lipid content and fatty acid composition of the small common wrasseSymphodus ocellatuswas analysed within two populations located in very different biotopes on the French shore: aCaulerpa taxifoliameadow located in Cap Martin and aPosidonia oceanicabed located in Villefranche. Polar lipids represented 82-90% of the total lipid in adult female livers, gonads and in eggs. Cholesterol in gonads and eggs and triacylglycerols in livers were the dominant neutral lipids. Differences in lipid classes were found in livers between the two populations, but not in their gonads and eggs. Moreover, a quantitative difference in total lipid content was evident. Young fish living on theC.taxifoliameadow in winter had 21% less lipid than those living on theP.oceanicabed. The populations ofS.ocellatusshowed differences between triacylglycerol versus phospholipid fatty acid compositions and between gonad versus liver fatty acid compositions. Moreover, a significant difference was found between both populations in their liver triacylglycerol fatty acid compositions, suggesting a difference in diet. Gut content analysis supported this hypothesis as it showed important differences in the ingested preys between the two populations in January (planktonic vs. benthic, frequency of isopods) and in June (frequency of gastropods). Thus, we found that the fish populations from Villefranche and Cap Martin showed significant differences in body lipids due to different nutritional habits. [ABSTRACT FROM AUTHOR]

The present work aimed to study metabolic utilization of energy and protein by juvenile European seabass reared at 25 °C and to estimate maintenance requirements, based on indirect calorimetry and nitrogen excretion measurements. Duplicate groups of fish (IBW = 22 g) were fed a practical diet, for 28 days, at ration levels of 0, 0.25, 0.5, 1 and 1.5% of body weight. At the end of this period, oxygen consumption and ammonia nitrogen excretion were measured in fed and unfed fish. Weight gain linearly increased with ration level. Feed efficiency significantly increased with nitrogen intake up to 0.68 g N/kg/day. Nitrogen retention (% N intake) was positive at all feeding levels, being maximum at 0.5% BW and then decreased with increasing ration levels. There was negative energy balance at the lowest ration level and significantly increased at higher ration levels. Daily oxygen consumption (g/kg body mass) and ammonia excretion (mg N–NH4/kg body mass) significantly increased with ration level. Heat production and heat increment of feeding (kJ/kg/day) remained low at low ration levels and significantly increased as ration level increased from 0.5 to 1.5% BW. Below maintenance, protein energy represented 34% of total energy expenditure and significantly increased to 49–56% above maintenance. Based on indirect calorimetry and ammonia excretion data, maintenance energy and protein requirements were estimated to be 56.8 kJ DE/kg/day and 1.15 g DP/kg/day, respectively. The efficiencies of energy and protein utilization were estimated to be 0.83 and 0.66, respectively. [ABSTRACT FROM AUTHOR]