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Chunde Wang - One of the best experts on this subject based on the ideXlab platform.
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transcriptomic and proteomic analyses of genetic factors influencing adductor muscle coloration in qn orange Scallops
BMC Genomics, 2019Co-Authors: Junlin Song, Chunde WangAbstract:Background Color polymorphism, a high-valued trait, is frequently observed in molluscan shellfish. The QN Orange scallop, a new scallop strain successively selected from the interspecific hybrids of the bay scallop (Argopecten irradians irradians) and the Peruvian scallop (Argopecten purpuratus), is distinguished from other Scallops by its orange adductor muscles. In this study, to reveal the mechanisms of the formation of adductor muscle coloration in the QN Orange Scallops, we compared the proteome and transcriptome of orange adductor muscles of the QN Orange and those of white adductor muscles of the Bohai Red scallop, another strain selected from the interspecific hybrids of the bay scallop and the Peruvian scallop.
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transcriptomic and proteomic analyses of genetic factors influencing adductor muscle coloration in qn orange Scallops
BMC Genomics, 2019Co-Authors: Junlin Song, Chunde WangAbstract:Color polymorphism, a high-valued trait, is frequently observed in molluscan shellfish. The QN Orange scallop, a new scallop strain successively selected from the interspecific hybrids of the bay scallop (Argopecten irradians irradians) and the Peruvian scallop (Argopecten purpuratus), is distinguished from other Scallops by its orange adductor muscles. In this study, to reveal the mechanisms of the formation of adductor muscle coloration in the QN Orange Scallops, we compared the proteome and transcriptome of orange adductor muscles of the QN Orange and those of white adductor muscles of the Bohai Red scallop, another strain selected from the interspecific hybrids of the bay scallop and the Peruvian scallop. Transcriptomic analysis revealed 416 differentially expressed genes (DEGs) between white and orange adductor muscles, among which 216 were upregulated and 200 were downregulated. Seventy-four differentially expressed proteins (DEPs), including 36 upregulated and 38 downregulated proteins, were identified through label-free proteomics. Among the identified DEGs and DEPs, genes related to carotenoids biosynthesis including apolipophorin, and Cytochrome P450 and those related to melanin biosynthesis including tyrosinase and Ras-related protein Rab-11A were found to express at higher levels in orange adductor muscles. The high expression levels of VPS (vacuolar protein sorting) and TIF (translation initiation factor) in orange adductor muscle tissues indicated that carotenoid accumulation may be affected by proteins outside of the carotenoid pathway. Our results implied that the coloration of orange adductor muscles in the QN Orange Scallops may be controlled by genes modulating accumulation of carotenoids and melanins. This study may provide valuable information for understanding the mechanisms and pathways underlying adductor muscle coloration in molluscan shellfish.
Kevin D. E. Stokesbury - One of the best experts on this subject based on the ideXlab platform.
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a comparison of drop camera and diver survey methods to monitor atlantic sea Scallops placopecten magellanicus in a small fishery closure
Journal of Shellfish Research, 2019Co-Authors: David N Bethoney, Caitlin Cleaver, Samuel C Asci, Skylar R Bayer, Richard A Wahle, Kevin D. E. StokesburyAbstract:Large-scale fishing closures are a leading tool in the spatial management of global ocean resources. This is exemplified in the U.S. Atlantic sea scallop (Placopecten magellanicus) fishery which uses a rotational scheme of temporary closed areas in both offshore and nearshore waters. The closed areas are generally hundreds to thousands square kilometers, but a group of inshore commercial scallop harvesters were interested in the effect of closing a much smaller area (3 km2), which had sustained valuable harvest before recent poor yields. To describe changes in scallop abundance and size within and around this closure, two independent surveys, a drop camera and diver transect, were conducted through industry–academic collaboration. In addition, this unusual union of a predominately offshore method, the drop camera, and inshore method, divers, was used to better interpret the results of each method. The drop camera survey results suggested that the closure significantly increased the biomass of exploitable Scallops, showing that even closure orders of magnitude smaller than commonly used for Scallops can be effective. Although the dive survey did not show this, understanding the uncertainties of each method helped resolve this discrepancy. Drop camera densities were calculated from a broader spatial area more representative of the entire area with increased sample size. By contrast, the dive survey provided an intensive description of Scallops at each individual survey site. Combining a drop camera survey with dive stations to collect scallop measurements would provide densities from a spatial scale representative of the study area while improving shell height frequency estimation and providing biological data. In addition, this project demonstrated how stakeholder engagement supported by academic institutions and fishery managers can allow intensive monitoring of small fishery closed areas outside of government assessments.
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Fisheries Sea Scallop, Placopecten magellanicus
Scallops - Biology Ecology Aquaculture and Fisheries, 2016Co-Authors: Kevin D. E. Stokesbury, Catherine E. O’keefe, Bradley P. HarrisAbstract:Abstract The sea scallop ( Placopecten magellanicus ) fisheries in the United States and Canada have experienced unprecedented rebuilding over the past 15 years. Several factors have led to the successful rebound of these industries, including revised management approaches, investments in improved survey technologies, data-rich stock assessments, favourable environmental conditions and some luck. There is no comprehensive understanding of the stock–recruitment relationship for Scallops, which complicates management of the species. Through the use of spatial and temporal management strategies, large recruitment events have been identified and juvenile Scallops can be protected until they reach a harvestable size. Identification and protection of such anomalous, large recruitment events in Canada and the United States over the past 15 years have rebuilt the stocks and sustained the fisheries. This chapter describes sea scallop life history, the ecosystem inhabited by sea Scallops, the composition of the Canadian and US fishing fleets, sea scallop stock assessments, resource surveys and sea scallop fisheries management.
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stock definition and recruitment implications for the u s sea scallop placopecten magellanicus fishery from 2003 to 2011
Reviews in Fisheries Science, 2012Co-Authors: Kevin D. E. StokesburyAbstract:The United States sea scallop management plan applies fishing mortality in a uniform manner, assigning a single value of instantaneous fishing mortality (F) to the entire resource. Applying a single value of fishing mortality assumes the scallop resource is a single population. Dividing the resource into Georges Bank and Mid-Atlantic Bight reveals that each has been either excessively fished or underutilized based on the present definition of optimum yield. The sea scallop resource was highest in 2003 and has declined by about 50,000 metric tons, entirely from the Mid-Atlantic Bight. Abundance and the corresponding harvest levels will likely continue if the resource is a single population and Scallops in the closed areas of Georges Bank populate the entire resource. Abundance and the corresponding harvest levels will likely decline if Georges Bank and the Mid-Atlantic Bight are separate populations in that Scallops within these areas have a closed lifecycle. The depletion of the large number of small scal...
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high densities of juvenile sea scallop placopecten magellanicus on banks and ledges in the central gulf of maine
Journal of Shellfish Research, 2010Co-Authors: Kevin D. E. Stokesbury, Bradley P. Harris, Jonathan D Carey, Catherine E OkeefeAbstract:ABSTRACT A video survey was conducted from August 10–14, 2009, to estimate sea scallop density, abundance, and size distribution on Platts Bank, Fippennies Ledge, Jeffreys Bank, Jeffreys Ledge, and Cashes Ledge in the central Gulf of Maine. Of the 298 km2 surveyed, 134 km2 (45%) had Scallops present. Scallop density was estimated using only stations containing at least 1 scallop. High densities of small Scallops occurred on all but Jeffreys Bank, where no Scallops were observed. Densities ranged from 1.56 Scallops/m2 on Jeffreys Ledge to 4.70 Scallops/m2 on Platts Bank, equaling an estimated abundance of 470 million Scallops. Less than 1% of Scallops were larger than 100 mm. Explanations for the lack of large individuals may include sporadic recruitment, high natural mortality from predation, or environmental influences. If these Scallops were to survive to harvestable size (approximately 102 mm), they could provide an important commercial resource worth approximately USS124 million.
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spatial and temporal variation in the shell height meat weight relationship of the sea scallop placopecten magellanicus in the georges bank fishery
Journal of Shellfish Research, 2009Co-Authors: Christopher L Sarro, Kevin D. E. StokesburyAbstract:ABSTRACT Spatial and temporal variations in the meat weight of sea Scallops were examined in the Georges Bank fishery. From 1998–2007, 31 commercial scallop vessels supplied 145 dissections from the last tow of their fishing trip. During the dissection process we recorded the shell height, meat weight, sex, gonad weight, and visceral tissue weight. Meat weight was regressed against shell height (Ln(MW) = α + β ln SH). Predicted meat weight varied by up to 29% for a 120 mm shell height scallop among months. Scallop meat weight varied by 31% for a 120 mm shell height scallop between areas in the same month. The Southern Flank of Georges Bank had a different pattern of monthly variation in meat weight, possibly because of a spring spawning event observed in the gonadal indices. These spatial and temporal differences in meat weight could affect harvest, and harvest rate, with a 22% difference in Scallops harvested between June and October calculated from a hypothetical fishery. Understanding these spatial and...
Junlin Song - One of the best experts on this subject based on the ideXlab platform.
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transcriptomic and proteomic analyses of genetic factors influencing adductor muscle coloration in qn orange Scallops
BMC Genomics, 2019Co-Authors: Junlin Song, Chunde WangAbstract:Background Color polymorphism, a high-valued trait, is frequently observed in molluscan shellfish. The QN Orange scallop, a new scallop strain successively selected from the interspecific hybrids of the bay scallop (Argopecten irradians irradians) and the Peruvian scallop (Argopecten purpuratus), is distinguished from other Scallops by its orange adductor muscles. In this study, to reveal the mechanisms of the formation of adductor muscle coloration in the QN Orange Scallops, we compared the proteome and transcriptome of orange adductor muscles of the QN Orange and those of white adductor muscles of the Bohai Red scallop, another strain selected from the interspecific hybrids of the bay scallop and the Peruvian scallop.
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transcriptomic and proteomic analyses of genetic factors influencing adductor muscle coloration in qn orange Scallops
BMC Genomics, 2019Co-Authors: Junlin Song, Chunde WangAbstract:Color polymorphism, a high-valued trait, is frequently observed in molluscan shellfish. The QN Orange scallop, a new scallop strain successively selected from the interspecific hybrids of the bay scallop (Argopecten irradians irradians) and the Peruvian scallop (Argopecten purpuratus), is distinguished from other Scallops by its orange adductor muscles. In this study, to reveal the mechanisms of the formation of adductor muscle coloration in the QN Orange Scallops, we compared the proteome and transcriptome of orange adductor muscles of the QN Orange and those of white adductor muscles of the Bohai Red scallop, another strain selected from the interspecific hybrids of the bay scallop and the Peruvian scallop. Transcriptomic analysis revealed 416 differentially expressed genes (DEGs) between white and orange adductor muscles, among which 216 were upregulated and 200 were downregulated. Seventy-four differentially expressed proteins (DEPs), including 36 upregulated and 38 downregulated proteins, were identified through label-free proteomics. Among the identified DEGs and DEPs, genes related to carotenoids biosynthesis including apolipophorin, and Cytochrome P450 and those related to melanin biosynthesis including tyrosinase and Ras-related protein Rab-11A were found to express at higher levels in orange adductor muscles. The high expression levels of VPS (vacuolar protein sorting) and TIF (translation initiation factor) in orange adductor muscle tissues indicated that carotenoid accumulation may be affected by proteins outside of the carotenoid pathway. Our results implied that the coloration of orange adductor muscles in the QN Orange Scallops may be controlled by genes modulating accumulation of carotenoids and melanins. This study may provide valuable information for understanding the mechanisms and pathways underlying adductor muscle coloration in molluscan shellfish.
A R Brand - One of the best experts on this subject based on the ideXlab platform.
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Benefits of closed area protection for a population of Scallops
Marine Ecology Progress Series, 2005Co-Authors: B. D. Beukers-stewart, Matthew W J Mosley, Belinda J. Vause, Helen L. Rossetti, A R BrandAbstract:Despite the current interest in using closed areas for fisheries management, few studies have actually examined the benefits for invertebrate fisheries such as Scallops. This study details the dynamics of a population of great Scallops Pecten maximus (L.), within a closed area and an adjacent fished area off the Isle of Man, over a 14 yr period (1989 to 2003). Scallop densities were very low in both areas when the closed area was set up, but increased at an accelerated rate over time within the closed area. Scallop densities also increased on the adjacent fishing ground, but not to the same extent. Consequently, the density of Scallops above the minimum legal landing size (110 mm SL) was more than 7 times higher in the closed area than in the fished area by 2003. There was also a shift towards much older and larger Scallops in the closed area and, correspondingly, lower estimates of total mortality. Experimental dredging of 2 plots within the closed area confirmed that fishing drove these differences in population dynamics and structure. These patterns of scallop density, age and size structure resulted in the exploitable biomass (adductor muscle and gonad) of Scallops being nearly 11 times higher in the closed area than in the fished area by 2003, and the reproductive biomass was 12.5 times higher. This is significant for fisheries management because the build up of high densities of large P. maximus individuals enhanced local reproductive potential and therefore the likelihood of export of larvae to the surrounding fishing grounds. Along with these direct benefits of closed area protection, juvenile Scallops had higher survival and individual growth rates in the closed area, apparently in response to reduced fishing disturbance. Although juvenile Scallops are not subject to direct removal by fishing, protection during this critical phase therefore appeared to assist the recovery of the closed area population. In summary, this study joins a growing number indicating that the use of closed areas offers a range of benefits over more traditional methods of managing fisheries. Fisheries for relatively sedentary and long-lived species such as P. maximus appear to be particularly suitable for this type of management.
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Biological control of fouling in suspended scallop cultivation.
Aquaculture, 2003Co-Authors: Katherine A. Ross, John P. Thorpe, A R BrandAbstract:Abstract Fouling of scallop shells and cultivation nets by living organisms is costly to remove and can reduce scallop growth. Here we investigate biological control of fouling in suspended scallop ( Pecten maximus ) cultivation. In preliminary trials in the Irish Sea, off the Isle of Man, sea urchins ( Echinus esculentus and Psammechinus miliaris ) and hermit crabs ( Pagurus spp.) removed fouling from nets more efficiently than did a range of other invertebrates. Sea urchins and hermit crabs were subsequently deployed from August 2000 to January 2001 at various densities (hermit crabs and E. esculentus at 1, 2, or 3 per net and P. miliaris at 3, 5 or 7 per net) in pearl nets containing Scallops. After 6 months, the survival of biological control organisms and their effect on scallop growth and mortality, and fouling of nets and scallop shells, were assessed. Only P. miliaris was associated with increased scallop shell growth, but no biological control organism reduced scallop growth or survival. All three biological control organisms significantly reduced the weight of fouling on nets (often by as much as 50%) and fouling of scallop shells; results were largely independent of biological control organism density. Sea urchins were most effective, removing hydroids and solitary tunicates efficiently; they could thus be commercially exploited alongside Scallops in a form of polyculture. These results suggest that biological control could be an efficient and environmentally sound method of addressing the problem of fouling in scallop cultivation.
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population dynamics and predictions in the isle of man fishery for the great scallop pecten maximus l
Ices Journal of Marine Science, 2003Co-Authors: B D Beukersstewart, Matthew W J Mosley, A R BrandAbstract:There has been a fishery for the great scallop, Pecten maximus, around the Isle of Man, since 1937. Research up to the end of the 1980s suggested that these scallop stocks were in continuous decline. The fishery is now largely dependent on the strength of each recruiting year-class, placing it at considerable risk from recruitment failure. This study utilised data on the spat settlement, age structure, abundance and commercial catch rates of Scallops, collected between 1975 and 2001, to examine recent population dynamics and the potential for predicting future catch rates. Spat settlement was generally low, but there were two exceptionally strong year-classes. Surveys of the stock revealed high exploitation rates during each fishing season (November to May inclusive) with variable recovery due to recruitment by the following October. In 1997/1998, scallop catch rates reached a 20-year high on several grounds and have generally remained high since. The strong spat settlements in 1989 and particularly 1994 were largely responsible for recent rises in catch rates, although the maintenance of high catch rates between 1999 and 2001 has occurred despite poor spat settlement between 1995 and 2000. Within stock surveys, the density of 2-year-old Scallops was generally an accurate predictor of the density of 3- and 4-year-old Scallops, 1-2 years later. The nature and strength of these relationships varied considerably between fishing grounds due to spatial variation in both scallop biology and patterns of exploitation. Results from fishery independent surveys did not always correlate well with commercial catch rates, however, suggesting the need for an expansion of the survey on some grounds. Overall, our study indicated that current levels of exploitation appear to be sustainable in the Isle of Man scallop fishery. Our results also demonstrated that monitoring of both spat settlement and the abundance of juveniles has considerable potential for predicting future catch rates of commercial sized Scallops.
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the effect of dredge capture on the escape response of the great scallop pecten maximus l implications for the survival of undersized discards
Journal of Experimental Marine Biology and Ecology, 2001Co-Authors: Stuart R. Jenkins, A R BrandAbstract:The effect of simulated dredge capture on the swimming escape response of the great scallop, Pecten maximus, was assessed in order to determine the potential for mortality in undersized discards. Three experiments were carried out: firstly, to determine how the effect of simulated dredging on the escape response varied with season and scallop size; secondly, to assess the time taken for Scallops to recover following simulated dredging; and thirdly, to determine the interactive effects of dredging, exposure to air and recovery time. In all experiments, simulated dredging caused a significant increase in the response time of Scallops and a significant decrease in the number of valve adductions performed. The negative effects of dredging occurred irrespective of season (spring versus autumn) and scallop size. Exposure to air also had a negative effect on the escape response, which was evident in both dredged and nondredged Scallops. Determination of the period taken to recover showed that although some recovery was evident after 1 h, the negative effects of simulated dredge capture were still apparent after a period of 24 h. These results suggest that there is a potential for high levels of mortality in undersized discarded Scallops, and Scallops which encounter dredges but are not captured.
Helu Liu - One of the best experts on this subject based on the ideXlab platform.
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Seasonal variation of total carotenoids content in the tissues of male and female golden noble Scallops Chlamys nobilis
'Elsevier BV', 2020Co-Authors: Helu Liu, Hong Kua Zhang, Lim, Leong Seng, Hongyu Ma, Huai Ping ZhengAbstract:The noble scallop Chlamys nobilis is an economically important edible marine bivalve that has been cultivated in the Southern Sea of China since the 1980s. Noble Scallops, particularly the golden Scallops, are rich in carotenoids, are of interest for their potential beneficial uses in human healthcare, food processing and pharmaceuticals. However, very little is known about the seasonal variation of total carotenoids content (TCC) in the golden Scallops. Therefore, present study was conducted to determine the seasonal variation of TCC in the tissues of male and female of golden Scallops. The results of present study revealed that the TCC in adductor, mantle and gonads of golden Scallops were ranged from 16.79 to 138.86 μg/ g, 92.86 to 312.98 μg/ g, and 71.5 to 750.0 μg/ g, respectively. Generally, the gonads of golden Scallops contain the highest TCC, followed by the mantle and adductor. In comparison of male and female Scallops, TCC in the same tissue (except for gonad) was not statistically significant. However, female gonads contain much higher TCC than male gonads. The temporal variation of the TCC in golden Scallops showed the highest in March to April and the lowest in October. The findings of current study can be very useful for scallop farmers and industry to determine the best harvest time to obtain the highest quality of golden Scallops with high TCC
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differential immune response of vitellogenin gene to vibrio anguillarum in noble scallop chlamys nobilis and its correlation with total carotenoid content
Fish & Shellfish Immunology, 2016Co-Authors: Qian Zhang, Huai Ping Zheng, Helu LiuAbstract:Vitellogenin (Vg), an egg yolk precursor protein, not only functions as a source of nutrients and a nonpolar molecular carrier that combine and transfer lipids, proteins, vitamin and carotenoids to oocytes during the oogenesis. but also links with the immune defense in many oviparous animals. To investigate whether Vg plays a immune defensive role in noble scallop Chlamys nobilis, an acute Vibrio anguillarum infection experiment was conducted in orange and brown Scallops with different carotenoids content. qRT-PCR result showed that Vg transcripts were significantly up-regulated after challenge with V. anguillarum in orange and brown shell Scallops compared to the control group and Vg expression reached the highest spot at 6 h, indicated that Vg possessed an immune function in the noble scallop. Interestingly, a significantly positive correlation between Vg transcript levels and total carotenoids content in the ovary was observed, indicating that Vg gene expression was up regulated by carotenoids. The results suggest that Vg is a potent immune protector and carotenoid may linked with Vg plays an important role in host immune system against pathogens in noble scallop C. nobilis.
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a de novo transcriptome of the noble scallop chlamys nobilis focusing on mining transcripts for carotenoid based coloration
BMC Genomics, 2015Co-Authors: Helu Liu, Huai Ping Zheng, Hongkuan Zhang, Longhui Deng, Wenhua Liu, Shuqi Wang, Fang Meng, Yajun Wang, Zhicheng GuoAbstract:The noble scallop Chlamys nobilis Reeve displays polymorphism in shell and muscle colors. Previous research showed that the orange Scallops with orange shell and muscle had a significantly higher carotenoid content than the brown ones with brown shell and white muscle. There is currently a need to identify candidate genes associated with carotenoid-based coloration. In the present study, 454 GS-FLX sequencing of noble scallop transcriptome yielded 1,181,060 clean sequence reads, which were assembled into 49,717 isotigs, leaving 110,158 reads as the singletons. Of the 159,875 unique sequences, 11.84% isotigs and 9.35% singletons were annotated. Moreover, 3,844 SSRs and over 120,000 high confidence variants (SNPs and INDELs) were identified. Especially, one class B scavenge receptor termed SRB-like-3 was discovered to express only in orange Scallops and absent in brown ones, suggesting a significant association with high carotenoid content. Down-regulation of SRB-like-3 mRNA by RNA interference remarkably decreased blood carotenoid, providing compelling evidence that SRB-like-3 is an ideal candidate gene controlling carotenoid deposition and determining orange coloration. Transcriptome analysis of noble scallop reveals a novel scavenger receptor significantly associated with orange scallop rich in carotenoid content. Our findings pave the way for further functional elucidation of this gene and molecular basis of carotenoid deposition in orange scallop.
