Short-neck Clam Ruditapes Philippinarum Research Articles

Temporal Dynamics in Energy Fluxes and Trophic Structure of a Portunus trituberculatus Polyculture Ecosystem During Different Culture Periods

Swimming crab (Portunus trituberculatus) are an important aquaculture species in eastern coastal areas of China. To improve the understanding of P. trituberculatus culture ecosystem functioning, the dynamics of energy flow and trophic structure of a P. trituberculatus polyculture system (co-culture with white shrimp Litopenaeus vannamei and short-necked clam Ruditapes philippinarum) were investigated in this study. Three Ecopath models representing the early, middle, and late culture periods of a P. trituberculatus polyculture ecosystem, respectively, were constructed to compare ecosystem traits at different culture periods. The results demonstrated that detritus was the main energy source in this polyculture ecosystem, and most of the total system throughput occurred at trophic levels I and II. Artificial food input and consumption by the culture organisms increased from early to middle and late periods, which produced marked impacts on biomass structure and primary production. R. philippinarum was considered to have a dominant influence on phytoplankton community dynamics which changed from nano- to pico-phytoplankton predominance, from the middle to the late period. Considering the low utilization efficiency of pico-phytoplankton production, large amounts of detritus accumulated in the sediment in the late period, which may constitute a potential risk for the ecosystem. Ecological network analyses indicated that the total energy flow and level of system organization increased from the early to the middle and late periods, whereas food web complexity and system resilience decreased from early to middle and late periods, which may indicate a trend of decreasing ecosystem stability. The system may be further optimized by increased stocking density of R. philippinarum and by introducing macro-algae at a suitable biomass to increase ecosystem stability, energy utilization efficiency, and aquaculture production.

Presence of Microplastics in Four Types of Shellfish Purchased at Fish Markets in Okayama City, Japan.

The worldwide microplastic pollution in our environment is a matter of great concern. Harmful effects of plastics have been reported in various types of organisms including murine animals. We examined the presence of microplastics in four types of shellfish purchased from fish markets in Okayama, Japan and served to the public: short-neck clam (Ruditapes philippinarum, asari in Japanese), hard-shell clam (Meretrix lusoria, hamaguri), brackishwater clam (Cyrenidae, shijimi), and oyster (Crassostrea gigas, kaki). Our analyses demonstrated that approx. 3 pieces of microplastics were present per single shellfish, based on the division of the total number of pieces of microplastic obtained from all 4 types of shellfish by the total number of shellfish examined. Since health problems in humans due to microplastics have not yet been confirmed, further examinations of the effects of ingested microplastics are needed.

Carbon budgets of two typical polyculture pond systems in coastal China and their potential roles in the global carbon cycle

The role of aquaculture systems in the global carbon cycle is poorly understood to date. We investigated the carbon budgets in 2 polyculture systems (PM: swimming crab Portunus trituberculatus with kuruma shrimp Marsupenaeus japonicus; and PMR: crab, shrimp and short-necked clam Ruditapes philippinarum) during the farming season (125 d in total). The main carbon input occurred via water (PM: 55.06%; PMR: 62.50%), followed by that via feed. PM absorbed 21.55 g C m-2 across the air-water interface, accounting for 13.27% of the total input. The carbon output via water was the main output in both PM (89.17%) and PMR (46.43%). PMR emitted 53.00 g C m-2 into the atmosphere during the farming season, accounting for 32.53% of the total output. The carbon output by harvested animals in PMR accounted for 19.48% of the total output, which was much higher than that in PM (5.71%). Carbon accumulation in the sediment was significantly higher in PM than in PMR (p < 0.05), but the value of both represented a small portion of the total output. Clam farming in the polyculture system profoundly altered the carbon budgets by changing the CO2 flux direction, reducing carbon accumulation in water and sediments and increasing the carbon output by harvested animals. In terms of the global warming potential, which was calculated from the results of CO2 and CH4 fluxes across the air-water interface, PM had the potential for mitigating the greenhouse effect on the 20 yr horizon, whereas PMR exacerbated global warming. Our results suggest that PM acted as a net carbon sink in the global carbon cycle, while PMR acted as a carbon source.

Carbon dioxide fluxes from two typical mariculture polyculture systems in coastal China

During the farming season of 2013 and 2014, carbon dioxide (CO2) fluxes at the water-air interface were determined from two typical seawater polyculture systems. The mean CO2 fluxes of 2013 and 2014 were − 0.316 ± 0.0674 μmol m−2 s−1 and -0.173 ± 0.242 μmol m−2 s−1 in the bi-species polyculture system of swimming crab (Portunus trituberculatus) with kuruma shrimp (Marsupenaeus japonicus) (PM) and 0.249 ± 0.251 μmol m−2 s−1 and 0.426 ± 0.151 μmol m−2 s−1 in the tri-species polyculture system of swimming crab with shrimp and short-necked clam (Ruditapes philippinarum) (PMR) (Negative flux values refer to CO2 uptake and positive values refer to CO2 emission). During the farming season, the CO2 budgets in PM and PMR were − 113.1 g CO2 m−2 and 154.0 g CO2 m−2, respectively. Water pH seemed like a stable indicator for CO2 flux and Chlorophyll a concentration was a key factor regulating the CO2 flux. Subsequent decreasing in water pH and Chl a concentration was supposed to be the main contributor changing the carbon source/sink function from a CO2 sink of PM to a CO2 source of PMR. Under the condition of current study, pH of 8.26 could be considered to be the critical value between influxes and effluxes in seawater crab-shrimp and crab-shrimp-clam polyculture systems.

Methane fluxes from typical marine polyculture ponds of swimming crab with kuruma shrimp and short-necked clam in eastern China

AEI Aquaculture Environment Interactions Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AEI 11:63-73 (2019) - DOI: https://doi.org/10.3354/aei00295 Methane fluxes from typical marine polyculture ponds of swimming crab with kuruma shrimp and short-necked clam in eastern China Dongxu Zhang1, Xiangli Tian1,*, Shuanglin Dong1, Yan Chen2, Jie Feng1, Rui-Peng He1, Kai Zhang3 1Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, PR China 2Beijing Aquatic Product Technology Promotion Department, Beijing 100029, PR China 3Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, PR China *Corresponding author: xianglitian@ouc.edu.cn ABSTRACT: Methane (CH4) fluxes at the water-air interface in 2 typical seawater polyculture systems were determined during the farming season. The mean CH4 fluxes were 66.0 ± 44.1 µg m-2 h-1 in the bispecies polyculture system of swimming crab Portunus trituberculatus with kuruma shrimp Marsupenaeus japonicus (PM) and 68.7 ± 39.5 µg m-2 h-1 in the trispecies polyculture system of swimming crab with shrimp and short-necked clam Ruditapes philippinarum (PMR), and no significant differences were observed between them. CH4 emissions showed temporal variability during the farming season, peaking in mid-August. The linear mixed-effect model demonstrated that air temperature was the main regulator of CH4 fluxes rather than the internal physical and chemical properties of the systems. Air, water and sediment temperatures explained 58.9, 61.4 and 55.3% of the CH4 flux variations in the PM and 64.6, 57.1 and 60.8% of the variations in the PMR, respectively. Reducing organic matter accumulation in the sediment by means of improving feeding efficiency and the application of integrated aquaculture are likely to be effective in reducing CH4 emissions from aquaculture systems. KEY WORDS: Methane fluxes · Temperature · Sediment characteristics · Seawater polyculture systems Full text in pdf format PreviousNextCite this article as: Zhang D, Tian X, Dong S, Chen Y, Feng J, He RP, Zhang K (2019) Methane fluxes from typical marine polyculture ponds of swimming crab with kuruma shrimp and short-necked clam in eastern China. Aquacult Environ Interact 11:63-73. https://doi.org/10.3354/aei00295 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AEI Vol. 11. Online publication date: February 21, 2019 Print ISSN: 1869-215X; Online ISSN: 1869-7534 Copyright © 2019 Inter-Research.

Trophic Interaction in a Portunus rituberculatus Polyculture Ecosystem Based on Carbon and Nitrogen Stable Isotope Analysis

Trophic interaction among various biomass groups in a swimming crab Portunus trituberculatus polyculture pond was investigated using carbon and nitrogen stable isotope analysis. The polycultured animal species also included white shrimp Litopenaeus vannamei, short-necked clam Ruditapes philippinarum, and redlip mullet Liza haematochila. The mean δ13C value for all the biomass groups in polyculture ecosystem ranged from −25.61‰ to −16.60‰, and the mean δ15N value ranged from 6.80‰ to 13.09‰. Significant difference in the δ13C value was found between particulate organic matter (POM) and sediment organic matter (SOM) (P < 0.05), indicating that these two organic matter pools have different material sources. Assuming that a 13C-enrichment factor of 1.00‰ and a 15N-enrichment factor of 2.70‰ existed between consumer and prey, diets of the four cultured animals were estimated using a stable isotope mixing model. The estimated model results indicated that P. trituberculatus mainly feed on Aloidis laevis; L. vannamei mainly feed on shrimp feed; while A. laevis, R. philippinarum and L. haematochelia mainly feed on POM. Shrimp feed was also an important food source of R. philippinarum and L. haematochelia. The diets of P. trituberculatus, L. vannamei, R. philippinarum, and L. haematochila showed complementary effects in this polyculture ecosystem. Our finding indicated that the polyculture of these four organisms with suitable farming density could make an effective use of most of the food sources, which can make a highly efficient polyculture ecosystem.

Comparative analysis of the energy fluxes and trophic structure of polyculture ecosystems of Portunus trituberculatus based on Ecopath model

This study investigated the energy flow and trophic structure of different polyculture ecosystems of the swimming crab Portunus trituberculatus using an Ecopath with Ecosim (EwE) model. Specifically, we aimed to characterize the trophic structure and biomass interactions, in parallel to assessing the energy utilization efficiency, of different ecosystems. Four treatments were designed, including the monoculture of P. trituberculatus (P), bi-species polyculture of P. trituberculatus with white shrimp Litopenaeus vannamei (PL), tri-species polyculture of P. trituberculatus with L. vannamei and short-necked clam Ruditapes philippinarum (PLR), and qua-species polyculture of P. trituberculatus with L. vannamei, R. philippinarum, and Gracilaria lichenoides (PLRG). Fourteen, 16, 17, and 18 functional groups were incorporated into models of the P, PL, PLR, and PLRG ecosystems, respectively. Macrozooplankton, macrobenthos, and Aloidis laevis consistently shared high keystoneness in all ecosystems, generating both bottom-up and top-down effects in all four ecosystems. Most of the total system throughput (TST) of the four ecosystems was distributed in trophic level I and II. The main energy flows were associated with benthic bacteria, bacterioplankton, L. vannamei, and P. trituberculatus in the PL, PLR, and PLRG ecosystems. The PLRG ecosystem has higher redundancy and overhead values than the other three ecosystems, indicating a stronger ability of resisting external perturbations. Overall, the PLRG ecosystem expressed the highest energy utilization efficiency, highest energy exports, and strongest ability of ecosystem stability among the four ecosystems, representing a sustainable P. trituberculatus polyculture pattern.

Fatty acids from controlled feeding as dietary markers of juvenile Chinese horseshoe crab, Tachypleus tridentatus

The potential use of fatty acid (FA) profile as a dietary tracer in juvenile Chinese horseshoe crab Tachypleus tridentatus was assessed in a feeding experiment. Selected feed was provided to the juveniles at various growth stages according to their food sources in the wild: larval and adult brine shrimp Artemia salina for the first six months, followed by a mixture of short-neck clam Ruditapes philippinarum and greasyback shrimp Metapenaeus ensis for a further six months. Juvenile horseshoe crab haemolymph and tissues of book gill, opisthosomal spine, chelicera and swimming leg were sampled after the feeding experiment. The FA profiles revealed that the juvenile haemolymph and various tissues had a total of 23–24 FA components. The major FA components consisted of saturated (palmitic and stearic) at 22–34%, monosaturated (oleic) at 7–34% and polyunsaturated (eicosapentaenoic and arachidonic) FAs at 9–27%. According to principal component analysis, the FA signatures of juvenile haemolymph were greatly influenced by the shift of food sources from brine shrimp to clam and shrimp meat, whereas the FA profiles of different tissues were more resistant to the nutrient alteration. The present findings confirmed that the FA profile of both juvenile haemolymph and different tissues reflected the FA composition of recent and previous diets, respectively; and thus may be useful in indicating the foraging information of juvenile horseshoe crabs in the field.

남해안 강진만에서 생산되는 굴 (Crassostrea gigas), 바지락 (Ruditapes philippinarum), 및 새꼬막 (Scapharca subcrenata) 의 위생학적 평가

남해안 강진만에서 생산되는 굴 (Crassostrea gigas), 바지락 (Ruditapes philippinarum), 및 새꼬막 (Scapharca subcrenata) 의 위생학적 평가

Marine microalgae as dietary supplements in the culture of juvenile Chinese horseshoe crabs,Tachypleus tridentatus(Xiphosura)

Five treatments (short-neck clam Ruditapes philippinarum and four formulated diets with the green microalgae Dunaliella tertiolecta or the golden-brown microalgae Isochrysis galbana in the ratio (dw/dw) of 5% or 10% to that of clam meat) were used to investigate the growth performance and haemolymph quality of juvenile Chinese horseshoe crabs Tachypleus tridentatus under laboratory culture. At the end of the 12-week study, various growth and moulting indicators as well as haemolymph biochemical parameters did not show any significant differences among the treatments. Significantly higher percentages of haemolymph amoebocyte viability and granular-spherical amoebocyte state were noted in both 5% and 10% I. galbana-supplemented diets compared to that of clam meat. However, the percentages of these two haemolymph parameters in juveniles fed with D. tertiolecta decreased significantly at the end of the experiment. Such differences were attributed to the presence of polyunsaturated fatty acid (PUFA), notably eicosapentaenoic acid (EPA), in I. galbana that was absent in D. tertiolecta and clam meat. Like many marine invertebrates, juvenile horseshoe crabs do not naturally obtain sufficient PUFAs from their diets to meet developmental and physiological needs; hence, supplementing microalgae with high levels of EPA in a protein-rich diet boosts immune competence and the health status of juvenile horseshoe crabs while under culture.

Growth-related changes in shell-length of short-neck clam Ruditapes philippinarum ingested by kuruma prawn Marsupenaeus japonicus

Growth-related changes in shell-length of short-neck clam Ruditapes philippinarum ingested by kuruma prawn Marsupenaeus japonicus

Use of Pyropia spheroplasts as a live food substitute for culturing Japanese short-neck clam Ruditapes philippinarum

Use of Pyropia spheroplasts as a live food substitute for culturing Japanese short-neck clam Ruditapes philippinarum

潜砂制限がアサリの成長に及ぼす影響

In Hakodate Bay, Hokkaido, the short-necked clam Ruditapes philippinarum shows highly depressed growth rate above 30 mm in shell length. In this area, clams often burrow into the sediment at an angle, which seems to be caused by boulders in the sediment. For benthic bivalves, burrowing into sediment is an important behavior to escape severe environmental conditions and predation. To examine possible effects of boulders on burrowing behavior and growth of the clam, we compared burrowing depth of the clams in contact with boulders and those clear of boulders. The ratio of burrowing depth to shell length was higher in those clear of boulders than those touching boulders. To understand this depressed growth mechanism, we carried out a field growth experiment and a laboratory feeding experiment. In the field experiment, we compared the shell growth increments of clams with restricted burrowing into sediment and those of unrestricted burrowing for three months. Shell growth increments of the clams with restricted burrowing were smaller regardless of their initial shell sizes. In the laboratory experiment, we compared the clearance rates of clams under six different situations: predatory crabs were present or not and burrowing treatments were unrestricted (deep sediment), restricted (shallow sediment) or impossible (i.e., no sediment). Both the presence of predators and restriction of burrowing decreased the clearance rate of clams; however their interaction was not significant. These results suggest boulders in the sediment restrict burrowing, and then depress shell growth of the clams. Sediment features must be taken into account for fishery analysis and stock recovery potential in clams with burrowing behavior.

An experimental study on the budget of organic carbon in polyculture systems of swimming crab with white shrimp and short-necked clam

The budget of organic carbon (OC) in polyculture systems of swimming crab Portunus trituberculatus, white shrimp Litopenaeus vannamei and short-necked clam Ruditapes philippinarum was studied with land-based enclosures from July 2 to October 3, 2012. Six treatments were designed, including monoculture of crab (C), polyculture of crab with shrimp (CS) and polyculture of crab with shrimp and clam (CSB1, CSB2, CSB3 and CSB4). Crab were stocked at 6ind/m2 in all treatments, and shrimp were stocked at 45ind/m2. Short-necked clam were stocked with crab and shrimp in four different densities, i.e., 7.5 (CSB1), 15 (CSB2), 30 (CSB3) and 60ind/m2 (CSB4). Results showed that the yield of crab was the highest in CSB4 system (P<0.05), while the survival rate and yield of white shrimp were highest in CSB3 system (P<0.05). The short-necked clam in CSB4 system exhibited the best yield (P<0.05). Primary production of phytoplankton and periphyton was the main input of OC, accounting for 46.08%–74.34%, and the feed provided 21.50%–51.40% of the total input. The major output of OC was biological and sediment respiration followed by accumulation in sediment, which accounted for 59.39%–68.61% and 21.86%–28.49%, respectively, of the total output. Accumulation of OC in the sediment of CSB1, CSB3 and CSB4 was significantly lower than the other systems (P<0.05). The CSB3 showed the highest efficiency of OC utilization and followed by the CSB4 (P<0.05). In conclusion, the optimum stocking density for the tri-species polyculture systems in this study was crab at 6ind/m2, shrimp at 45ind/m2, and short-necked clam at 30–60ind/m2, which exhibited better ecological efficiency and economic benefit.

Effect of Seasonal Temperature on Oxygen Uptake and Ciliary Movement in the Japanese Short-neck Clam Ruditapes philippinarum

Effect of Seasonal Temperature on Oxygen Uptake and Ciliary Movement in the Japanese Short-neck Clam Ruditapes philippinarum

MPN 및 H-NS 유전자를 표적으로 하는 PCR assay를 병용한 장염비브리오(Vibrio parahaemolyticus)의 정량

【We applied a combination of most probable number-polymerase chain reaction (MPN-PCR) methods using a PCR procedure targeting the H-NS (VP1133) gene to detect Vibrio parahaemolyticus presence and density in seawater as well as within short-necked clam Ruditapes philippinarum tissues collected from Gomso Bay, Korea. In 30 seawater samples, V. parahaemolyticus levels ranged from less than 1.8 to $1.1{\times}10^3MPN/100mL$ , and samples from August showed higher than those from other months. Furthermore, the levels of V. parahaemolyticus in six short-necked clam samples ranged from $7.8{\times}10^2$ to $2.1{\times}10^3MPN/100g$ , approximately 2.5 times higher than in seawater samples from the corresponding month. Our results provide data on V. parahaemolyticus contamination in seawater and short-necked clam tissues, and help to improve quantitative methods of assessing V. parahaemolytcius levels.】

Purification and Antioxidant Property of Antioxidative Oligopeptide from Short-Necked Clam (Ruditapes philippinarum) Hydrolysate In Vitro

Short-necked clam (Ruditapes philippinarum) muscle was hydrolyzed with trypsin, and the antioxidant activities of isolated peptides were investigated. The hydrolysate was fractionated by chromatographic methods using Sephadex G-25 gel filtration and Hypersil BDS C18 reversed phase high performance liquid chromatography (RP-HPLC). The antioxidant activities of the hydrolysate were determined by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power assay, and the protective effect against hydroxyl-radical-induced DNA damage. The amino acid sequence of the purified antioxidant oligopeptide was found to be Gly-Asp-Gln-Gln-Lys.

Hemolymph quality as indicator of health status in juvenile Chinese horseshoe crab Tachypleus tridentatus (Xiphosura) under laboratory culture

The growth performance and hemolymph quality of juvenile Chinese horseshoe crabs under four diet treatments: brine shrimp Artemia salina, short-neck clam Ruditapes philippinarum, sandworm Marphysa sanguinea and mixed clam and sandworm were evaluated in a 12-week experiment. The growth responses in terms of final body weight, specific growth rates and percentage of individuals molted under the clam diet were significantly higher than those fed with brine shrimp and sandworm, whereas the mixed clam and sandworm diet was not statistically different from the other three treatments. While the hemolymph properties among these diets were similar, significant declines in hemocyanin concentration, percentage of oxyhemocyanin, and ratio of granular–spherical to granular–flattened states of amebocytes were noted at the end of the study. Such a decrease in hemolymph quality indicated deleterious effects due to prolonged culture on the health status of the juveniles, which might be attributed to captivity-related issues, such as deficiencies of essential diet compositions, movement constraints and absence of tidal rhythms. This was further supported from the finding that the hemolymph quality of the experimental juveniles was significantly poor compared to that of the juveniles collected from the field. Changes of hemolymph constituents could thus be a useful indicator to reflect the health status of juvenile horseshoe crabs under laboratory culture.

Molecular and morphological evidence of hybridization between native Ruditapes philippinarum and the introduced Ruditapes form in Japan

Abstract Marine aquaculture and stock enhancement are major causes of the introduction of alien species. A good example of such an introduction is the Japanese shortneck clam Ruditapes philippinarum, one of the most important fishery resources in the world. To meet the domestic shortage of R. philippinarum caused by depleted catches, clams were imported to Japan from China and the Korean peninsula. The imported clam is an alien species that has a very similar morphology, and was misidentified as R. philippinarum (hereafter, Ruditapes form). We genotyped 1,186 clams of R. philippinarum and R. form at four microsatellite loci, sequenced mitochondrial DNA (COI gene fragment) of 485 clams, 34 of which were R. variegatus, and measured morphometric and meristic characters of 754 clams from 12 populations in Japan and China, including the Ariake Sea and Tokyo Bay, where large numbers of R. form were released. Our analyses confirmed that R. form was from the genus Ruditapes, and the genetic differentiation between R. philippinarum and R. form was distinct, but small, compared with five bivalve outgroups. However, R. form had distinct shell morphology, especially larger numbers of radial ribs on the shell surface, suggesting that R. form might be a new Ruditapes species or a variation of R. philippinarum that originated from southern China. A genetic affinity of the sample from the Ariake Sea to R. form was found with the intermediate shell morphology and number of radial ribs, and the hybrid proportion was estimated at 51.3 ± 4.6 % in the Ariake Sea.

수산생물 종류별 마비성 패류독소 축적 및 정화

To compare the accumulation of paralytic shellfish poison (PSP) in different marine organisms, the occurrence and variation of PSP were surveyed in blue mussel Mytilus edulis, oyster Crassostrea gigas, short neck clam Ruditapes philippinarum, bay scallop Argopecten irradians, and warty sea squirt Styela clava collected from Jinhae Bay, Korea, in 2005 and 2006 year. We also investigated the ability of the blue mussel to detoxify PSP by relaying and depuration (via the water flow or water circulation system). In the marine organisms examined, PSP levels were the highest in blue mussel, followed in order by bay scallop, oyster, short neck clam, and warty sea squirt. Comparing the maximum PSP levels in the bivalve species examined in 2005 and 2006, PSP in blue mussel was 1.6-2.0, 4.0-5.9, and 5.1-6.0 times higher than in bay scallop, oyster, and short neck clam, respectively. Therefore, blue mussel could be useful as a bioindicator for PSP monitoring. With the increasing PSP levels in blue mussel in 2006, the proportion of PSP in its digestive gland increased to 95.1% when the maximum level was detected from the whole tissues of blue mussel on May 29. Subsequently, the PSP proportion in the digestive gland decreased as the PSP level in whole tissue decreased. The detoxification of PSP in blue mussel was greatest with relaying, followed by the water flow, and water circulation systems. Relaying decreased the PSP level below the regulatory limit of <TEX>$80{\mu}g$</TEX>/100 g after 2 days in low toxic sample with <TEX>$124{\mu}g$</TEX>/100 g, and after 7 days in high toxic sample with <TEX>$401{\mu}g$</TEX>/100 g. During depuration in the blue mussel with <TEX>$401{\mu}g$</TEX>/100 g via the water flow system, the PSP amounts in the digestive gland decreased by about 50% after 1 day, and about 77% after 7 days. In contrast, the PSP amounts in the soft body, gill, and mantle did not change significantly with depuration.