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Sample records for a-exposed atlantic cod

  1. Harvesting Atlantic Cod under Climate Variability

    NASA Astrophysics Data System (ADS)

    Oremus, K. L.

    2016-12-01

    Previous literature links the growth of a fishery to climate variability. This study uses an age-structured bioeconomic model to compare optimal harvest in the Gulf of Maine Atlantic cod fishery under a variable climate versus a static climate. The optimal harvest path depends on the relationship between fishery growth and the interest rate, with higher interest rates dictating greater harvests now at the cost of long-term stock sustainability. Given the time horizon of a single generation of fishermen under assumptions of a static climate, the model finds that the economically optimal management strategy is to harvest the entire stock in the short term and allow the fishery to collapse. However, if the biological growth of the fishery is assumed to vary with climate conditions, such as the North Atlantic Oscillation, there will always be pulses of high growth in the stock. During some of these high-growth years, the growth of the stock and its economic yield can exceed the growth rate of the economy even under high interest rates. This implies that it is not economically optimal to exhaust the New England cod fishery if NAO is included in the biological growth function. This finding may have theoretical implications for the management of other renewable yet exhaustible resources whose growth rates are subject to climate variability.

  2. Transcriptome analysis of gill tissue of Atlantic cod Gadus morhua L. from the Baltic Sea.

    PubMed

    Małachowicz, Magdalena; Kijewska, Agnieszka; Wenne, Roman

    2015-10-01

    The Atlantic cod (Gadus morhua L.) is one of the most ecologically and economically important marine fish species in the North Atlantic Ocean. Using Roche GS-FLX 454 pyrosequencing technique 962,516 reads, representing 379Mbp of the Baltic cod transcriptome, were obtained. Data was assembled into 14,029 contigs of which 100% displayed homology to the Atlantic cod transcriptome. Despite a high similarity between transcripts, evidence for significant differences between Baltic and Atlantic cod was found.

  3. Experimental mycobacteriosis in Atlantic cod, Gadus morhua L.

    PubMed

    Zerihun, M A; Colquhoun, D J; Poppe, T T

    2012-05-01

    Piscine mycobacteriosis causes losses in a number of fish species both in the wild and in aquaculture worldwide. Mycobacterium salmoniphilum infections have on several occasions been reported in farmed Atlantic salmon, Salmo salar L. The present study tested and confirmed the susceptibility of Atlantic cod, Gadus morhua L., an important yet relatively novel aquaculture species, to infection with M. salmoniphilum. Atlantic cod injected intraperitoneally with a suspension of this bacterium were maintained together with cohabitant (COH) fish in a flow-through marine water system at 10-11 °C. The fish were supervised daily and samples taken at 2, 7, 14, 23, 34 and 53 weeks post-infection and examined pathologically, bacteriologically and using molecular biology. Injected mycobacteria were re-isolated in high concentrations from both injected and COH fish groups. Death attributable to mycobacterial infection was observed in both injected (47%) and COH (28%) fish groups. Extensive development of granuloma in visceral organs, mainly the mesenteries, spleen, kidney and liver (lesser extent) and at later stages of the infection in heart tissues and gills, was observed in both injected and COH fish. Granulomas underwent a temporal progression of distinct morphological stages, culminating in well-circumscribed lesions surrounded by normal or healing tissue. Acid-fast bacilli were detected in both granulomas and non-granulomatous tissues. This study confirms that Atlantic cod is highly susceptible to M. salmoniphilum infection and that this bacterial species may be a threat to cod both in the wild and in the aquaculture.

  4. Behavioral responses of Atlantic cod to sea temperature changes

    PubMed Central

    Freitas, Carla; Olsen, Esben Moland; Moland, Even; Ciannelli, Lorenzo; Knutsen, Halvor

    2015-01-01

    Understanding responses of marine species to temperature variability is essential to predict impacts of future climate change in the oceans. Most ectotherms are expected to adjust their behavior to avoid extreme temperatures and minimize acute changes in body temperature. However, measuring such behavioral plasticity in the wild is challenging. Combining 4 years of telemetry-derived behavioral data on juvenile and adult (30–80 cm) Atlantic cod (Gadus morhua), and in situ ocean temperature measurements, we found a significant effect of sea temperature on cod depth use and activity level in coastal Skagerrak. During summer, cod were found in deeper waters when sea surface temperature increased. Further, this effect of temperature was stronger on larger cod. Diel vertical migration, which consists in a nighttime rise to shallow feeding habitats, was stronger among smaller cod. As surface temperature increased beyond ∼15°C, their vertical migration was limited to deeper waters. In addition to larger diel vertical migrations, smaller cod were more active and travelled larger distances compared to larger specimens. Cold temperatures during winter tended, however, to reduce the magnitude of diel vertical migrations, as well as the activity level and distance moved by those smaller individuals. Our findings suggest that future and ongoing rises in sea surface temperature may increasingly deprive cod in this region from shallow feeding areas during summer, which may be detrimental for local populations of the species. PMID:26045957

  5. Behavioral responses of Atlantic cod to sea temperature changes.

    PubMed

    Freitas, Carla; Olsen, Esben Moland; Moland, Even; Ciannelli, Lorenzo; Knutsen, Halvor

    2015-05-01

    Understanding responses of marine species to temperature variability is essential to predict impacts of future climate change in the oceans. Most ectotherms are expected to adjust their behavior to avoid extreme temperatures and minimize acute changes in body temperature. However, measuring such behavioral plasticity in the wild is challenging. Combining 4 years of telemetry-derived behavioral data on juvenile and adult (30-80 cm) Atlantic cod (Gadus morhua), and in situ ocean temperature measurements, we found a significant effect of sea temperature on cod depth use and activity level in coastal Skagerrak. During summer, cod were found in deeper waters when sea surface temperature increased. Further, this effect of temperature was stronger on larger cod. Diel vertical migration, which consists in a nighttime rise to shallow feeding habitats, was stronger among smaller cod. As surface temperature increased beyond ∼15°C, their vertical migration was limited to deeper waters. In addition to larger diel vertical migrations, smaller cod were more active and travelled larger distances compared to larger specimens. Cold temperatures during winter tended, however, to reduce the magnitude of diel vertical migrations, as well as the activity level and distance moved by those smaller individuals. Our findings suggest that future and ongoing rises in sea surface temperature may increasingly deprive cod in this region from shallow feeding areas during summer, which may be detrimental for local populations of the species.

  6. Potential Use of Atlantic Cod Trypsin in Biomedicine

    PubMed Central

    Gudmundsdóttir, Ágústa; Hilmarsson, Hilmar; Stefansson, Bjarki

    2013-01-01

    Surface proteins of viruses and bacteria used for cell attachment and invasion are candidates for degradation by proteases. Trypsin from Atlantic cod (Gadus morhua) was previously demonstrated to have efficacy against influenza viruses in vitro and on skin. In this paper, cod trypsin is shown to be 3–12 times more effective in degrading large native proteins than its mesophilic analogue, bovine trypsin. This is in agreement with previous findings where cod trypsin was found to be the most active among twelve different proteases in cleaving various cytokines and pathological proteins. Furthermore, our results show that cod trypsin has high efficacy against herpes simplex virus type 1 (HSV-1) and the respiratory syncytial virus (RSV) in vitro. The results on the antipathogenic properties of cod trypsin are important because rhinovirus, RSV, and influenza are the most predominant pathogenic viruses in upper respiratory tract infections. Results from a clinical study presented in this paper show that a specific formulation containing cod trypsin was preferred for wound healing over other methods used in the study. Apparently, the high digestive ability of the cold-adapted cod trypsin towards large native proteins plays a role in its efficacy against pathogens and its positive effects on wounds. PMID:23555095

  7. Genomic characterization of the Atlantic cod sex-locus

    PubMed Central

    Star, Bastiaan; Tørresen, Ole K.; Nederbragt, Alexander J.; Jakobsen, Kjetill S.; Pampoulie, Christophe; Jentoft, Sissel

    2016-01-01

    A variety of sex determination mechanisms can be observed in evolutionary divergent teleosts. Sex determination is genetic in Atlantic cod (Gadus morhua), however the genomic location or size of its sex-locus is unknown. Here, we characterize the sex-locus of Atlantic cod using whole genome sequence (WGS) data of 227 wild-caught specimens. Analyzing more than 55 million polymorphic loci, we identify 166 loci that are associated with sex. These loci are located in six distinct regions on five different linkage groups (LG) in the genome. The largest of these regions, an approximately 55 Kb region on LG11, contains the majority of genotypes that segregate closely according to a XX-XY system. Genotypes in this region can be used genetically determine sex, whereas those in the other regions are inconsistently sex-linked. The identified region on LG11 and its surrounding genes have no clear sequence homology with genes or regulatory elements associated with sex-determination or differentiation in other species. The functionality of this sex-locus therefore remains unknown. The WGS strategy used here proved adequate for detecting the small regions associated with sex in this species. Our results highlight the evolutionary flexibility in genomic architecture underlying teleost sex-determination and allow practical applications to genetically sex Atlantic cod. PMID:27499266

  8. Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae.

    PubMed

    Penglase, S; Harboe, T; Sæle, O; Helland, S; Nordgreen, A; Hamre, K

    2013-01-01

    Copepods as feed promote better growth and development in marine fish larvae than rotifers. However, unlike rotifers, copepods contain several minerals such as iodine (I), at potentially toxic levels. Iodine is an essential trace element and both under and over supply of I can inhibit the production of the I containing thyroid hormones. It is unknown whether marine fish larvae require copepod levels of I or if mechanisms are present that prevent I toxicity. In this study, larval Atlantic cod (Gadus morhua) were fed rotifers enriched to intermediate (26 mg I kg(-1) dry weight; MI group) or copepod (129 mg I kg(-1) DW; HI group) I levels and compared to cod larvae fed control rotifers (0.6 mg I kg(-1) DW). Larval I concentrations were increased by 3 (MI) and 7 (HI) fold compared to controls during the rotifer feeding period. No differences in growth were observed, but the HI diet increased thyroid follicle colloid to epithelium ratios, and affected the essential element concentrations of larvae compared to the other groups. The thyroid follicle morphology in the HI larvae is typical of colloid goitre, a condition resulting from excessive I intake, even though whole body I levels were below those found previously in copepod fed cod larvae. This is the first observation of dietary induced I toxicity in fish, and suggests I toxicity may be determined to a greater extent by bioavailability and nutrient interactions than by total body I concentrations in fish larvae. Rotifers with 0.6 mg I kg(-1) DW appeared sufficient to prevent gross signs of I deficiency in cod larvae reared with continuous water exchange, while modelling of cod larvae versus rotifer I levels suggests that optimum I levels in rotifers for cod larvae is 3.5 mg I kg(-1) DW.

  9. Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae

    PubMed Central

    Penglase, S; Harboe, T; Sæle, Ø; Helland, S; Nordgreen, A

    2013-01-01

    Copepods as feed promote better growth and development in marine fish larvae than rotifers. However, unlike rotifers, copepods contain several minerals such as iodine (I), at potentially toxic levels. Iodine is an essential trace element and both under and over supply of I can inhibit the production of the I containing thyroid hormones. It is unknown whether marine fish larvae require copepod levels of I or if mechanisms are present that prevent I toxicity. In this study, larval Atlantic cod (Gadus morhua) were fed rotifers enriched to intermediate (26 mg I kg-1 dry weight; MI group) or copepod (129 mg I kg-1 DW; HI group) I levels and compared to cod larvae fed control rotifers (0.6 mg I kg-1 DW). Larval I concentrations were increased by 3 (MI) and 7 (HI) fold compared to controls during the rotifer feeding period. No differences in growth were observed, but the HI diet increased thyroid follicle colloid to epithelium ratios, and affected the essential element concentrations of larvae compared to the other groups. The thyroid follicle morphology in the HI larvae is typical of colloid goitre, a condition resulting from excessive I intake, even though whole body I levels were below those found previously in copepod fed cod larvae. This is the first observation of dietary induced I toxicity in fish, and suggests I toxicity may be determined to a greater extent by bioavailability and nutrient interactions than by total body I concentrations in fish larvae. Rotifers with 0.6 mg I kg-1 DW appeared sufficient to prevent gross signs of I deficiency in cod larvae reared with continuous water exchange, while modelling of cod larvae versus rotifer I levels suggests that optimum I levels in rotifers for cod larvae is 3.5 mg I kg-1 DW. PMID:23638355

  10. Mitochondrial acclimation potential to ocean acidification and warming of Polar cod (Boreogadus saida) and Atlantic cod (Gadus morhua).

    PubMed

    Leo, Elettra; Kunz, Kristina L; Schmidt, Matthias; Storch, Daniela; Pörtner, Hans-O; Mark, Felix C

    2017-01-01

    Ocean acidification and warming are happening fast in the Arctic but little is known about the effects of ocean acidification and warming on the physiological performance and survival of Arctic fish. In this study we investigated the metabolic background of performance through analyses of cardiac mitochondrial function in response to control and elevated water temperatures and PCO2 of two gadoid fish species, Polar cod (Boreogadus saida), an endemic Arctic species, and Atlantic cod (Gadus morhua), which is a temperate to cold eurytherm and currently expanding into Arctic waters in the wake of ocean warming. We studied their responses to the above-mentioned drivers and their acclimation potential through analysing the cardiac mitochondrial function in permeabilised cardiac muscle fibres after 4 months of incubation at different temperatures (Polar cod: 0, 3, 6, 8 °C and Atlantic cod: 3, 8, 12, 16 °C), combined with exposure to present (400μatm) and year 2100 (1170μatm) levels of CO2. OXPHOS, proton leak and ATP production efficiency in Polar cod were similar in the groups acclimated at 400μatm and 1170μatm of CO2, while incubation at 8 °C evoked increased proton leak resulting in decreased ATP production efficiency and decreased Complex IV capacity. In contrast, OXPHOS of Atlantic cod increased with temperature without compromising the ATP production efficiency, whereas the combination of high temperature and high PCO2 depressed OXPHOS and ATP production efficiency. Polar cod mitochondrial efficiency decreased at 8 °C while Atlantic cod mitochondria were more resilient to elevated temperature; however, this resilience was constrained by high PCO2. In line with its lower habitat temperature and higher degree of stenothermy, Polar cod has a lower acclimation potential to warming than Atlantic cod.

  11. Phenotypic flexibility of digestive system in Atlantic cod (Gadus morhua).

    PubMed

    Blier, P U; Dutil, J-D; Lemieux, H; Bélanger, F; Bitetera, L

    2007-02-01

    This study examined the restoration of the digestive capacity of Atlantic cod (Gadus morhua Linnaeus) following a long period of food deprivation. Fifty cod (48 cm, 1 kg) were food-deprived for 68 days and then fed in excess with capelin (Mallotus villosus Müller) on alternate days. Ten fish were sampled after 0, 2, 6, 14 and 28 days and the mass of the pyloric caeca, intestine and carcass determined. Two metabolic enzymes (cytochrome c oxidase and citrate synthase) were assayed in white muscle, pyloric caeca and intestine, and trypsin activity was measured in the pyloric caeca. A delay of 14 days was required before body mass started to increase markedly, whereas most of the increase in mass of both the pyloric caeca and intestine relative to fish length occurred earlier in the experiment. By day 14, the activities of trypsin and citrate synthase in the pyloric caeca as well as citrate synthase in the intestine had reached maxima. The growth of the digestive tissues and restoration of their metabolic capacities thus occur early upon refeeding and are likely required for recovery growth to take place. The phenotypic flexibility of the cod digestive system is therefore remarkable: increases in trypsin activity and size of pyloric caeca resulted in a combined 29-fold increase in digestive capacity of the fish during the refeeding period. Our study suggests that Atlantic cod are able to cope with marked fluctuations in food availability in their environment by making a rapid adjustment of their digestive capacity as soon as food availability increases.

  12. The genome sequence of Atlantic cod reveals a unique immune system.

    PubMed

    Star, Bastiaan; Nederbragt, Alexander J; Jentoft, Sissel; Grimholt, Unni; Malmstrøm, Martin; Gregers, Tone F; Rounge, Trine B; Paulsen, Jonas; Solbakken, Monica H; Sharma, Animesh; Wetten, Ola F; Lanzén, Anders; Winer, Roger; Knight, James; Vogel, Jan-Hinnerk; Aken, Bronwen; Andersen, Oivind; Lagesen, Karin; Tooming-Klunderud, Ave; Edvardsen, Rolf B; Tina, Kirubakaran G; Espelund, Mari; Nepal, Chirag; Previti, Christopher; Karlsen, Bård Ove; Moum, Truls; Skage, Morten; Berg, Paul R; Gjøen, Tor; Kuhl, Heiner; Thorsen, Jim; Malde, Ketil; Reinhardt, Richard; Du, Lei; Johansen, Steinar D; Searle, Steve; Lien, Sigbjørn; Nilsen, Frank; Jonassen, Inge; Omholt, Stig W; Stenseth, Nils Chr; Jakobsen, Kjetill S

    2011-08-10

    Atlantic cod (Gadus morhua) is a large, cold-adapted teleost that sustains long-standing commercial fisheries and incipient aquaculture. Here we present the genome sequence of Atlantic cod, showing evidence for complex thermal adaptations in its haemoglobin gene cluster and an unusual immune architecture compared to other sequenced vertebrates. The genome assembly was obtained exclusively by 454 sequencing of shotgun and paired-end libraries, and automated annotation identified 22,154 genes. The major histocompatibility complex (MHC) II is a conserved feature of the adaptive immune system of jawed vertebrates, but we show that Atlantic cod has lost the genes for MHC II, CD4 and invariant chain (Ii) that are essential for the function of this pathway. Nevertheless, Atlantic cod is not exceptionally susceptible to disease under natural conditions. We find a highly expanded number of MHC I genes and a unique composition of its Toll-like receptor (TLR) families. This indicates how the Atlantic cod immune system has evolved compensatory mechanisms in both adaptive and innate immunity in the absence of MHC II. These observations affect fundamental assumptions about the evolution of the adaptive immune system and its components in vertebrates.

  13. Yersiniosis in Atlantic cod, Gadus morhua (L.), characterization of the infective strain and host reactions.

    PubMed

    Gudmundsdottir, B K; Gudmundsdottir, S; Gudmundsdottir, S; Magnadottir, B

    2014-06-01

    A disease outbreak in farmed Atlantic cod caused by Yersinia ruckeri is reported. Mortality started following vaccination of cod reared in two tanks (A and B). The accumulated mortality reached 1.9% in A and 4.8% in B in the following 30 days when treatment with oxytetracycline was applied. Biochemical and molecular analysis of Y. ruckeri isolates from the cod and other fish species from fresh and marine waters in Iceland revealed a high salinity-tolerant subgroup of Y. ruckeri serotype O1. Infected fish showed clinical signs comparable with those of Y. ruckeri -infected salmonids, with the exception of granuloma formations in infected cod tissues, which is a known response of cod to bacterial infections. Immunohistological examination showed Y. ruckeri antigens in the core of granulomas and the involvement of immune parameters that indicates a strong association between complement and lysozyme killing of bacteria. Experimental infection of cod with a cod isolate induced disease, and the calculated LD50 was 1.7 × 10(4) CFU per fish. The results suggest that yersiniosis can be spread between populations of freshwater and marine fish. Treatment of infected cod with antibiotic did not eliminate the infection, which can be explained by the immune response of cod producing prolonged granulomatous infection.

  14. Adaptation to Low Salinity Promotes Genomic Divergence in Atlantic Cod (Gadus morhua L.).

    PubMed

    Berg, Paul R; Jentoft, Sissel; Star, Bastiaan; Ring, Kristoffer H; Knutsen, Halvor; Lien, Sigbjørn; Jakobsen, Kjetill S; André, Carl

    2015-05-20

    How genomic selection enables species to adapt to divergent environments is a fundamental question in ecology and evolution. We investigated the genomic signatures of local adaptation in Atlantic cod (Gadus morhua L.) along a natural salinity gradient, ranging from 35‰ in the North Sea to 7‰ within the Baltic Sea. By utilizing a 12 K SNPchip, we simultaneously assessed neutral and adaptive genetic divergence across the Atlantic cod genome. Combining outlier analyses with a landscape genomic approach, we identified a set of directionally selected loci that are strongly correlated with habitat differences in salinity, oxygen, and temperature. Our results show that discrete regions within the Atlantic cod genome are subject to directional selection and associated with adaptation to the local environmental conditions in the Baltic- and the North Sea, indicating divergence hitchhiking and the presence of genomic islands of divergence. We report a suite of outlier single nucleotide polymorphisms within or closely located to genes associated with osmoregulation, as well as genes known to play important roles in the hydration and development of oocytes. These genes are likely to have key functions within a general osmoregulatory framework and are important for the survival of eggs and larvae, contributing to the buildup of reproductive isolation between the low-salinity adapted Baltic cod and the adjacent cod populations. Hence, our data suggest that adaptive responses to the environmental conditions in the Baltic Sea may contribute to a strong and effective reproductive barrier, and that Baltic cod can be viewed as an example of ongoing speciation.

  15. Elucidation of different cold-adapted Atlantic cod (Gadus morhua) trypsin X isoenzymes.

    PubMed

    Stefansson, Bjarki; Sandholt, Gunnar B; Gudmundsdottir, Ágústa

    2017-01-01

    Trypsins from Atlantic cod (Gadus morhua), consisting of several isoenzymes, are highly active cold-adapted serine proteases. These trypsins are isolated for biomedical use in an eco-friendly manner from underutilized seafood by-products. Our group has explored the biochemical properties of trypsins and their high potential in biomedicine. For broader utilization of cod trypsins, further characterization of biochemical properties of the individual cod trypsin isoenzymes is of importance. For that purpose, a benzamidine purified trypsin isolate from Atlantic cod was analyzed. Anion exchange chromatography revealed eight peaks containing proteins around 24kDa with tryptic activity. Based on mass spectrometric analysis, one isoenzyme gave the best match to cod trypsin I and six isoenzymes gave the best match to cod trypsin X. Amino terminal sequencing of two of these six trypsin isoenzymes showed identity to cod trypsin X. Three sequence variants of trypsin X were identified by cDNA analysis demonstrating that various forms of this enzyme exist. One trypsin X isoenzyme was selected for further characterization based on abundance and stability. Stepwise increase in catalytic efficiency (kcat/Km) of this trypsin X isoenzyme was obtained with substrates containing one to three amino acid residues. The study demonstrates that the catalytic efficiency of this trypsin X isoenzyme is comparable to that of cod trypsin I, the most abundant and highly active isoenzyme in the benzamidine cod trypsin isolate. Differences in pH stability and sensitivity to inhibitors of the trypsin X isoenzyme compared to cod trypsin I were detected that may be important for practical use.

  16. Expression of vasa and nanos3 during primordial germ cell formation and migration in Atlantic cod (Gadus morhua L.).

    PubMed

    Presslauer, C; Nagasawa, K; Fernandes, J M O; Babiak, I

    2012-10-01

    Primordial germ cells (PGCs), progenitors of gametes, are specified very early in embryonic development and undergo an active migration to the site where the future gonads will form. While the developmental pattern of PGCs during embryogenesis has been documented in few model teleost fishes, there is currently no information available for any representative of Superorder Paracanthopterygii. This includes Atlantic cod (Gadus morhua), which is a historically important food fish in both fisheries and aquaculture industries. In the present study, we cloned and characterized vasa and nanos3 and used them as germ cell markers in Atlantic cod. Sequencing results showed prospective vasa and nanos3 mRNA contained the domains used to describe their respective protein family. Furthermore, phylogenetic analysis using the amino acid sequence placed Atlantic cod Vasa distinct from representatives of three other taxonomic Superorders. Atlantic cod Nanos3 was placed with other homologues from the Nanos3 subfamily. Expression of both genes was detected from the first cleavage division; both were specifically expressed in Atlantic cod PGCs from the 32-cell stage. While nanos3 expression ceased during early somitogenesis, vasa was strongly expressed throughout embryonic development. Using vasa as a marker, we described the Atlantic cod PGC migration pattern. We demonstrated that Atlantic cod PGCs migrate ventral to the trunk mesoderm. With the exception of Pacific herring (Clupea pallasii), PGCs in other described teleost fishes migrate lateral to the trunk. The results from this study are the first step toward understanding germ line formation in Atlantic cod.

  17. Flow cytometry assays of respiratory burst in Atlantic salmon (Salmo salar L.) and in Atlantic cod (Gadus morhua L.) leucocytes.

    PubMed

    Kalgraff, Cathrine A K; Wergeland, Heidrun I; Pettersen, Eirin Fausa

    2011-09-01

    The oxidation of dihydrorhodamine 123 (DHR) to the fluorescent rhodamine 123 (RHO) was detected using flow cytometry. This assay for detection of respiratory burst activity was established in peripheral blood leucocytes (PBL) and head kidney leucocytes (HKL) of Atlantic salmon and Atlantic cod. The leucocytes were stimulated by phorbol 12-myristate 13-acetate (PMA). For cod cells 10 times lower concentration of PMA had to be used compared to salmon cells, as higher concentrations were toxic and resulted in considerable cell death. The cells found to be RHO-positive were monocytes/macrophages and neutrophils based on the scatter dot plots, but for salmon also some small cells were found to have high fluorescence intensity both in the flow cytometry analyses and by fluorescence microscopy of cytospin preparations. The nature of these cells is not known. For cod leucocytes, such cells were not obvious. The instrument settings are a bit more demanding for cod, as cod cells die more easily compared to salmon cells. In both assays the limit between negative and positive cells has to be carefully considered. The presented flow cytometry protocols for measurements of respiratory burst in salmon and cod leucocytes can be applied in various studies where respiratory burst functions are involved, such as to verify if it is activated or suppressed in connection with infections and immunostimulation.

  18. Why does the immune system of Atlantic cod lack MHC II?

    PubMed

    Star, Bastiaan; Jentoft, Sissel

    2012-08-01

    MHC II, a major feature of the adaptive immune system, is lacking in Atlantic cod, and there are different scenarios (metabolic cost hypothesis or functional shift hypothesis) that might explain this loss. The lack of MHC II coincides with an increased number of genes for MHC I and Toll-like receptors (TLRs).

  19. Genomic Sequencing of Ranaviruses Isolated from Turbot (Scophthalmus maximus) and Atlantic Cod (Gadus morhua)

    PubMed Central

    Steckler, Natalie K.; Olesen, Niels J.; Waltzek, Thomas B.

    2016-01-01

    Ranaviruses have been isolated from Atlantic cod (Gadus morhua) and turbot (Scophthalmus maximus) in Denmark. Phylogenomic analyses revealed that these two ranaviruses are nearly identical and form a distinct clade at the base of the ranavirus tree branching off near other fish ranaviruses. PMID:27979944

  20. Genomic analysis of the host response to nervous necrosis virus in Atlantic cod (Gadus morhua) brain.

    PubMed

    Krasnov, Aleksei; Kileng, Øyvind; Skugor, Stanko; Jørgensen, Sven Martin; Afanasyev, Sergey; Timmerhaus, Gerrit; Sommer, Ann-Inger; Jensen, Ingvill

    2013-07-01

    Genome sequencing combined with transcriptome profiling promotes exploration of defence against pathogens and discovery of immune genes. Based on sequences from the recently released genome of Atlantic cod, a genome-wide oligonucleotide microarray (ACIQ-1) was designed and used for analyses of gene expression in the brain during infection with nervous necrosis virus (NNV). A challenge experiment with NNV was performed with Atlantic cod juveniles and brain samples from virus infected and uninfected fish were used for microarray analysis. Expression of virus induced genes increased at 5 days post challenge and persisted at stable level to the last sampling at 25 days post challenge. A large fraction of the up-regulated genes (546 features) were known or expected to have immune functions and most of these have not previously been characterized in Atlantic cod. Transcriptomic changes induced by the virus involved strong activation of genes associated with interferon and tumour necrosis factor related responses and acute inflammation. Up-regulation of genes involved in adaptive immunity suggested a rapid recruitment of B and T lymphocytes to the NNV infected brain. QPCR analyses of 15 candidate genes of innate immunity showed rapid induction by poly(I:C) in Atlantic cod larvae cells suggesting an antiviral role. Earliest and greatest expression changes after poly I:C stimulation was observed for interferon regulatory factors IRF4 and IRF7. Comparative studies between teleost species provided new knowledge about the evolution of innate antiviral immunity in fish. A number of genes is present or responds to viruses only in fish. Innate immunity of Atlantic cod is characterized by selective expansion of several medium-sized multigene families with ribose binding domains. An interesting finding was the high representation of three large gene families among the early antiviral genes, including tripartite motif proteins (TRIM) and proteins with PRY-SPRY and NACHT domains. The

  1. Influence of photoperiod on expression of DNA (cytosine-5) methyltransferases in Atlantic cod.

    PubMed

    Giannetto, Alessia; Nagasawa, Kazue; Fasulo, Salvatore; Fernandes, Jorge M O

    2013-05-01

    Photoperiod manipulation during early juvenile stages can influence growth in Atlantic cod. In the present study, one group of cod juveniles were reared under natural photoperiod conditions for Bodø (67° N, 14° E), whereas their counterparts were kept under continuous illumination. The mean weight of juvenile cod reared under continuous illumination was found to be 13% greater than those kept under natural photoperiod after 120days of light treatment. The molecular basis of this phenotypic plasticity is currently unknown but it is likely that DNA (cytosine-5)-methyltransferases (dnmts) are involved, since these genes play a crucial role in epigenetic regulation of gene expression. Phylogenetic analysis of Atlantic cod dnmt1, dnmt2 and dnmt3a revealed that within each group, the phylogeny follows the taxonomic relationship between the various species and comparative mapping of dnmt paralogues showed that these genes lie within regions of conserved synteny amongst teleosts. Of the three dnmt paralogues, dnmt3a had the highest expression in fast muscle of adult cod. In addition, dnmt1 and dnmt2 were differentially expressed between tissues but with prominent expression in gonads. Dnmt1 and dnmt3a transcript levels showed a significant increase in fast muscle of juvenile cod from the continuous light group at several time points. Remarkably, dnmt1 and dnmt3a transcript levels were 2-fold higher at 120days, by which point photoperiod conditions between the two light groups had become identical. Our data revealed that photoperiod can have an extended effect on expression of dnmt genes, which may be involved in the epigenetic regulation of muscle growth by photoperiod in Atlantic cod.

  2. Characterization of Atlantic cod spawning habitat and behavior in Icelandic coastal waters.

    PubMed

    Grabowski, Timothy B; Boswell, Kevin M; McAdam, Bruce J; Wells, R J David; Marteinsdóttir, Guđrún

    2012-01-01

    The physical habitat used during spawning may potentially be an important factor affecting reproductive output of broadcast spawning marine fishes, particularly for species with complex, substrate-oriented mating systems and behaviors, such as Atlantic cod Gadus morhua. We characterized the habitat use and behavior of spawning Atlantic cod at two locations off the coast of southwestern Iceland during a 2-d research cruise (15-16 April 2009). We simultaneously operated two different active hydroacoustic gear types, a split beam echosounder and a dual frequency imaging sonar (DIDSON), as well as a remotely operated underwater vehicle (ROV). A total of five fish species were identified through ROV surveys: including cusk Brosme brosme, Atlantic cod, haddock Melanogrammus aeglefinus, lemon sole Microstomus kitt, and Atlantic redfish Sebastes spp. Of the three habitats identified in the acoustic surveys, the transitional habitat between boulder/lava field and sand habitats was characterized by greater fish density and acoustic target strength compared to that of sand or boulder/lava field habitats independently. Atlantic cod were observed behaving in a manner consistent with published descriptions of spawning. Individuals were observed ascending 1-5 m into the water column from the bottom at an average vertical swimming speed of 0.20-0.25 m s(-1) and maintained an average spacing of 1.0-1.4 m between individuals. Our results suggest that cod do not choose spawning locations indiscriminately despite the fact that it is a broadcast spawning fish with planktonic eggs that are released well above the seafloor.

  3. Characterization of Atlantic cod spawning habitat and behavior in Icelandic coastal waters

    USGS Publications Warehouse

    Grabowski, Timothy B.; Boswell, Kevin M.; McAdam, Bruce J.; Wells, R. J. David; Marteinsdóttir, Gudrún

    2012-01-01

    The physical habitat used during spawning may potentially be an important factor affecting reproductive output of broadcast spawning marine fishes, particularly for species with complex, substrate-oriented mating systems and behaviors, such as Atlantic cod Gadus morhua. We characterized the habitat use and behavior of spawning Atlantic cod at two locations off the coast of southwestern Iceland during a 2-d research cruise (15–16 April 2009). We simultaneously operated two different active hydroacoustic gear types, a split beam echosounder and a dual frequency imaging sonar (DIDSON), as well as a remotely operated underwater vehicle (ROV). A total of five fish species were identified through ROV surveys: including cusk Brosme brosme, Atlantic cod, haddock Melanogrammus aeglefinus, lemon sole Microstomus kitt, and Atlantic redfish Sebastes spp. Of the three habitats identified in the acoustic surveys, the transitional habitat between boulder/lava field and sand habitats was characterized by greater fish density and acoustic target strength compared to that of sand or boulder/lava field habitats independently. Atlantic cod were observed behaving in a manner consistent with published descriptions of spawning. Individuals were observed ascending 1–5 m into the water column from the bottom at an average vertical swimming speed of 0.20–0.25 m s−1 and maintained an average spacing of 1.0–1.4 m between individuals. Our results suggest that cod do not choose spawning locations indiscriminately despite the fact that it is a broadcast spawning fish with planktonic eggs that are released well above the seafloor.

  4. Daily Rhythmicity of Clock Gene Transcripts in Atlantic Cod Fast Skeletal Muscle

    PubMed Central

    Lazado, Carlo C.; Kumaratunga, Hiruni P. S.; Nagasawa, Kazue; Babiak, Igor; Giannetto, Alessia; Fernandes, Jorge M. O.

    2014-01-01

    The classical notion of a centralized clock that governs circadian rhythmicity has been challenged with the discovery of peripheral oscillators that enable organisms to cope with daily changes in their environment. The present study aimed to identify the molecular clock components in Atlantic cod (Gadus morhua) and to investigate their daily gene expression in fast skeletal muscle. Atlantic cod clock genes were closely related to their orthologs in teleosts and tetrapods. Synteny was conserved to varying degrees in the majority of the 18 clock genes examined. In particular, aryl hydrocarbon receptor nuclear translocator-like 2 (arntl2), RAR-related orphan receptor A (rora) and timeless (tim) displayed high degrees of conservation. Expression profiling during the early ontogenesis revealed that some transcripts were maternally transferred, namely arntl2, cryptochrome 1b and 2 (cry1b and cry2), and period 2a and 2b (per2a and per2b). Most clock genes were ubiquitously expressed in various tissues, suggesting the possible existence of multiple peripheral clock systems in Atlantic cod. In particular, they were all detected in fast skeletal muscle, with the exception of neuronal PAS (Per-Arnt-Single-minded) domain-containing protein (npas1) and rora. Rhythmicity analysis revealed 8 clock genes with daily rhythmic expression, namely arntl2, circadian locomotor output cycles kaput (clock), npas2, cry2, cry3 per2a, nuclear receptor subfamily 1, group D, member 1 (nr1d1), and nr1d2a. Transcript levels of the myogenic genes myogenic factor 5 (myf5) and muscleblind-like 1 (mbnl1) strongly correlated with clock gene expression. This is the first study to unravel the molecular components of peripheral clocks in Atlantic cod. Taken together, our data suggest that the putative clock system in fast skeletal muscle of Atlantic cod has regulatory implications on muscle physiology, particularly in the expression of genes related to myogenesis. PMID:24921252

  5. Characterization of Atlantic Cod Spawning Habitat and Behavior in Icelandic Coastal Waters

    PubMed Central

    Grabowski, Timothy B.; Boswell, Kevin M.; McAdam, Bruce J.; Wells, R. J. David; Marteinsdóttir, Guđrún

    2012-01-01

    The physical habitat used during spawning may potentially be an important factor affecting reproductive output of broadcast spawning marine fishes, particularly for species with complex, substrate-oriented mating systems and behaviors, such as Atlantic cod Gadus morhua. We characterized the habitat use and behavior of spawning Atlantic cod at two locations off the coast of southwestern Iceland during a 2-d research cruise (15–16 April 2009). We simultaneously operated two different active hydroacoustic gear types, a split beam echosounder and a dual frequency imaging sonar (DIDSON), as well as a remotely operated underwater vehicle (ROV). A total of five fish species were identified through ROV surveys: including cusk Brosme brosme, Atlantic cod, haddock Melanogrammus aeglefinus, lemon sole Microstomus kitt, and Atlantic redfish Sebastes spp. Of the three habitats identified in the acoustic surveys, the transitional habitat between boulder/lava field and sand habitats was characterized by greater fish density and acoustic target strength compared to that of sand or boulder/lava field habitats independently. Atlantic cod were observed behaving in a manner consistent with published descriptions of spawning. Individuals were observed ascending 1–5 m into the water column from the bottom at an average vertical swimming speed of 0.20–0.25 m s−1 and maintained an average spacing of 1.0–1.4 m between individuals. Our results suggest that cod do not choose spawning locations indiscriminately despite the fact that it is a broadcast spawning fish with planktonic eggs that are released well above the seafloor. PMID:23236471

  6. Ontogeny of redox regulation in Atlantic cod (Gadus morhua) larvae.

    PubMed

    Hamre, Kristin; Penglase, Samuel J; Rasinger, Josef D; Skjærven, Kaja H; Olsvik, Pål A

    2014-08-01

    The reduction potential of a cell is related to its fate. Proliferating cells are more reduced than those that are differentiating, whereas apoptotic cells are generally the most oxidized. Glutathione is considered the most important cellular redox buffer and the average reduction potential (Eh) of a cell or organism can be calculated from the concentrations of glutathione (GSH) and glutathione disulfide (GSSG). In this study, triplicate groups of cod larvae at various stages of development (3 to 63 days post-hatch; dph) were sampled for analyses of GSSG/2GSH concentrations, together with activities of antioxidant enzymes and expression of genes encoding proteins involved in redox metabolism. The concentration of total GSH (GSH+GSSG) increased from 610 ± 100 to 1260 ± 150 μmol/kg between 7 and 14 dph and was then constant until 49 dph, after which it decreased to 810 ± 100 μmol/kg by 63 dph. The 14- to 49-dph period, when total GSH concentrations were stable, coincides with the proposed period of metamorphosis in cod larvae. The concentration of GSSG comprised approximately 1% of the total GSH concentration and was stable throughout the sampling series. This resulted in a decreasing Eh from -239 ± 1 to -262 ± 7 mV between 7 and 14 dph, after which it remained constant until 63 dph. The changes in GSH and Eh were accompanied by changes in the expression of several genes involved in redox balance and signaling, as well as changes in activities of antioxidant enzymes, with the most dynamic responses occurring in the early phase of cod larval development. It is hypothesized that metamorphosis in cod larvae starts with the onset of mosaic hyperplasia in the skeletal muscle at approximately 20 dph (6.8mm standard length (SL)) and ends with differentiation of the stomach and disappearance of the larval finfold at 40 to 50 dph (10-15 mm SL). Thus, metamorphosis in cod larvae seems to coincide with high and stable total concentrations of GSH.

  7. Localization and functional properties of two galectin-1 proteins in Atlantic cod (Gadus morhua) mucosal tissues.

    PubMed

    Rajan, Binoy; Kiron, Viswanath; Fernandes, Jorge M O; Brinchmann, Monica F

    2013-06-01

    Galectin-1 is a β-galactoside binding lectin with multiple immune functions in higher vertebrates. We report the characterization of two galectin-1 proteins from Atlantic cod, with emphasis on mucosal tissues. Tissue distribution of these two ≈14kDa galectin-1 proteins (Codgal1-1 and Codgal1-2) was ascertained by western blotting of one dimensional (1D) and two dimensional (2DE) gels. The two galectin-1 proteins were differentially localized in the mucosal tissues of cod. Codgal1-1 was predominantly localized in the basal cells of skin and this protein was present in all the early developmental stages examined, indicating a likely involvement in developmental processes. The two lectins were also localized in the adherent macrophage-like cells (MLC) from cod head kidney and results gathered indicate their possible secretion during Francisella noatunensis infection, suggesting that they are active components of immune defence. Lactose affinity chromatography coupled with gel filtration co-purified the two cod galectin-1 proteins, which hemagglutinated horse red blood cells in a lactose inhibitable manner. They also could bind and agglutinate both Gram-positive and Gram-negative bacteria. This study suggests multiple functional roles for galectin-1, especially in development and innate immune response of Atlantic cod. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Three chromosomal rearrangements promote genomic divergence between migratory and stationary ecotypes of Atlantic cod.

    PubMed

    Berg, Paul R; Star, Bastiaan; Pampoulie, Christophe; Sodeland, Marte; Barth, Julia M I; Knutsen, Halvor; Jakobsen, Kjetill S; Jentoft, Sissel

    2016-03-17

    Identification of genome-wide patterns of divergence provides insight on how genomes are influenced by selection and can reveal the potential for local adaptation in spatially structured populations. In Atlantic cod - historically a major marine resource - Northeast-Arctic- and Norwegian coastal cod are recognized by fundamental differences in migratory and non-migratory behavior, respectively. However, the genomic architecture underlying such behavioral ecotypes is unclear. Here, we have analyzed more than 8.000 polymorphic SNPs distributed throughout all 23 linkage groups and show that loci putatively under selection are localized within three distinct genomic regions, each of several megabases long, covering approximately 4% of the Atlantic cod genome. These regions likely represent genomic inversions. The frequency of these distinct regions differ markedly between the ecotypes, spawning in the vicinity of each other, which contrasts with the low level of divergence in the rest of the genome. The observed patterns strongly suggest that these chromosomal rearrangements are instrumental in local adaptation and separation of Atlantic cod populations, leaving footprints of large genomic regions under selection. Our findings demonstrate the power of using genomic information in further understanding the population dynamics and defining management units in one of the world's most economically important marine resources.

  9. Three chromosomal rearrangements promote genomic divergence between migratory and stationary ecotypes of Atlantic cod

    PubMed Central

    Berg, Paul R.; Star, Bastiaan; Pampoulie, Christophe; Sodeland, Marte; Barth, Julia M. I.; Knutsen, Halvor; Jakobsen, Kjetill S.; Jentoft, Sissel

    2016-01-01

    Identification of genome-wide patterns of divergence provides insight on how genomes are influenced by selection and can reveal the potential for local adaptation in spatially structured populations. In Atlantic cod – historically a major marine resource – Northeast-Arctic- and Norwegian coastal cod are recognized by fundamental differences in migratory and non-migratory behavior, respectively. However, the genomic architecture underlying such behavioral ecotypes is unclear. Here, we have analyzed more than 8.000 polymorphic SNPs distributed throughout all 23 linkage groups and show that loci putatively under selection are localized within three distinct genomic regions, each of several megabases long, covering approximately 4% of the Atlantic cod genome. These regions likely represent genomic inversions. The frequency of these distinct regions differ markedly between the ecotypes, spawning in the vicinity of each other, which contrasts with the low level of divergence in the rest of the genome. The observed patterns strongly suggest that these chromosomal rearrangements are instrumental in local adaptation and separation of Atlantic cod populations, leaving footprints of large genomic regions under selection. Our findings demonstrate the power of using genomic information in further understanding the population dynamics and defining management units in one of the world’s most economically important marine resources. PMID:26983361

  10. Adaptation to Low Salinity Promotes Genomic Divergence in Atlantic Cod (Gadus morhua L.)

    PubMed Central

    Berg, Paul R.; Jentoft, Sissel; Star, Bastiaan; Ring, Kristoffer H.; Knutsen, Halvor; Lien, Sigbjørn; Jakobsen, Kjetill S.; André, Carl

    2015-01-01

    How genomic selection enables species to adapt to divergent environments is a fundamental question in ecology and evolution. We investigated the genomic signatures of local adaptation in Atlantic cod (Gadus morhua L.) along a natural salinity gradient, ranging from 35‰ in the North Sea to 7‰ within the Baltic Sea. By utilizing a 12 K SNPchip, we simultaneously assessed neutral and adaptive genetic divergence across the Atlantic cod genome. Combining outlier analyses with a landscape genomic approach, we identified a set of directionally selected loci that are strongly correlated with habitat differences in salinity, oxygen, and temperature. Our results show that discrete regions within the Atlantic cod genome are subject to directional selection and associated with adaptation to the local environmental conditions in the Baltic- and the North Sea, indicating divergence hitchhiking and the presence of genomic islands of divergence. We report a suite of outlier single nucleotide polymorphisms within or closely located to genes associated with osmoregulation, as well as genes known to play important roles in the hydration and development of oocytes. These genes are likely to have key functions within a general osmoregulatory framework and are important for the survival of eggs and larvae, contributing to the buildup of reproductive isolation between the low-salinity adapted Baltic cod and the adjacent cod populations. Hence, our data suggest that adaptive responses to the environmental conditions in the Baltic Sea may contribute to a strong and effective reproductive barrier, and that Baltic cod can be viewed as an example of ongoing speciation. PMID:25994933

  11. Novel mannose binding natterin-like protein in the skin mucus of Atlantic cod (Gadus morhua).

    PubMed

    Rajan, Binoy; Patel, Deepti M; Kitani, Yoichiro; Viswanath, Kiron; Brinchmann, Monica F

    2017-09-01

    This study presents the first report of purification of natterin-like protein (Nlp) in a non-venomous fish. The peptide identities of purified cod Nlp were confirmed through LC-MSMS and matched to a cod expressed sequence tag (EST). A partial cod nlp nucleotide sequence was amplified and sequenced based on this EST. Multiple sequence alignment of cod Nlp showed considerable homology with other teleost Nlps and the presence of an N-terminal jacalin-like lectin domain coupled with a C-terminal toxin domain. nlp expression was higher in skin, head kidney, liver and spleen than in other tissues studied. Hemaggluttination of horse red blood cells by Nlp was calcium dependent and inhibited by mannose. A Vibrio anguillarum bath challenge however, did not alter the expression of cod nlp transcripts in the skin and gills. Further functional characterization is required to establish the significance of this unique protein in Atlantic cod and other teleosts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effect of petroleum aromatic hydrocarbons on monogeneids parasitizing Atlantic cod, Gadus morhua L

    SciTech Connect

    Khan, R.A.; Kiceniuk, J.W.

    1988-07-01

    Fish gills appear to be more susceptible than other tissues to toxicants. The latter include petroleum aromatic hydrocarbons, which can induce lesions characterized by excessive mucus secretion, hyperplasia, fusion of secondary gill lamellae and capillary dilation. Fish are also natural hosts to several species of ectoparasites, especially monogeneans which live among the gill filaments. A previous study on the interrelation of water quality, gill parasites and gill pathology provided evidence that fish living in habitats degraded by pollutants such as Biscayne Bay, Florida, were heavily infested with monogeneids especially when gill lesions were severe. Atlantic cod, Gadus morhua, are hosts to monogeneans. The authors reported previously that crude oil fractions induced gill lesions in cod and also affected some gastrointestinal parasites. In the light of these reports, a study was undertaken to ascertain whether any relationship existed between gill lesions and gill parasites in cod following chronic exposure to petroleum hydrocarbons.

  13. Photoperiod influences growth and mll (mixed-lineage leukaemia) expression in Atlantic cod.

    PubMed

    Nagasawa, Kazue; Giannetto, Alessia; Fernandes, Jorge M O

    2012-01-01

    Photoperiod is associated to phenotypic plasticity of somatic growth in several teleost species. However, the molecular mechanisms underlying this phenomenon are currently unknown but it is likely that epigenetic regulation by methyltransferases is involved. The MLL (mixed-lineage leukaemia) family comprises histone methyltransferases that play a critical role in regulating gene expression during early development in mammals. So far, these genes have received scant attention in teleost fish. In the present study, the mean weight of Atlantic cod juveniles reared under continuous illumination was found to be 13% greater than those kept under natural photoperiod conditions for 120 days. We newly determined cDNA sequences of five mll (mll1, mll2, mll3a, mll4b and mll5) and two setd1 (setd1a and setd1ba) paralogues from Atlantic cod. Phylogenetic analysis revealed that the cod genes clustered within the appropriate mll clade and comparative mapping of mll paralogues showed that these genes lie within a region of conserved synteny among teleosts. All mll and setd1 genes were highly expressed in gonads and fast muscle of adult cod, albeit at different levels, and they were differentially regulated with photoperiod in muscle of juvenile fish. Following only one day of exposure to constant light, mll1, mll4b and setd1a were up to 57% lower in these fish compared to the natural photoperiod group. In addition, mRNA expression of myogenic regulatory factors (myog and myf-5) and pax7 in fast muscle was also affected by different photoperiod conditions. Notably, myog was significantly elevated in the continuous illumination group throughout the time course of the experiment. The absence of a day/night cycle is associated with a generalised decrease in mll expression concomitant with an increase in myog transcript levels in fast muscle of Atlantic cod, which may be involved in the observed epigenetic regulation of growth by photoperiod in this species.

  14. Irreversible binding of o,p'-DDD in interrenal cells of Atlantic cod (Gadus morhua).

    PubMed

    Lindhe, Orjan; Brandt, Ingvar; Christiansen, Jørgen Schou; Ingebrigtsen, Kristian

    2003-03-01

    Precision-cut tissue slices of the anterior kidney from Atlantic cod (Gadus morhua) were prepared with a Krumdieck tissue slicer and exposed to 2-(2-chlorophenyl)-2-(4-chloro-(14C)phenyl)-1,1-dichlorethane (o,p(')-[14C]DDD) in vitro. Microautoradiography revealed irreversible o,p(')-DDD-derived binding confined to the glucocorticoid producing interrenal cells (adrenocortical analogues). This cell-selective binding was confirmed by means of autoradiography at different levels of resolution on Atlantic cod administered o,p(')-[14C]DDD intragastrically. The results provide evidence for a site-specific metabolic activation and irreversible binding of o,p(')-DDD in the interrenal cells, which, in turn, may modify glucocorticoid homeostasis.

  15. Identification of the Atlantic cod L-amino acid oxidase and its alterations following bacterial exposure.

    PubMed

    Kitani, Yoichiro; Fernandes, Jorge M O; Kiron, Viswanath

    2015-06-01

    Antibacterial factors that are present in epidermal mucus of fish have a potential role in the first line of host defence to bacterial pathogens. This study reports the identification of L-amino acid oxidase (LAO) in Atlantic cod (GmLao) and the changes in the molecule following bacterial exposure. The gmlao transcripts and LAO activity were present on both the body surface and in the internal organs of the fish. Relative mRNA level of gmlao increased significantly in the gills, the spleen and the head kidney (up to 8-fold) of fish that were challenged with the pathogen Vibrio anguillarum. The gmlao expression in skin was 4-fold higher in challenged fish. Our data indicate that LAO may be an important effector of antibacterial defence in Atlantic cod.

  16. Effects of perimortem stress on farmed Atlantic cod product quality: a baseline study.

    PubMed

    Erikson, Ulf; Digre, Hanne; Misimi, Ekrem

    2011-05-01

    The potential effects of handling stress on the product quality of farmed Atlantic cod were studied in a controlled experiment (fish anesthetized with metomidate or isoeugenol, or subjected to stress by chasing for 30 min). For comparison, stress and fillet quality was also studied for commercially slaughtered farmed cod (fish sampled from waiting cage, after pumping and stunning with carbon dioxide, and after bleeding and chilling). Baseline values for stress-related parameters (blood chemistry, muscle high-energy phosphates and inosine monophospate, initial pH, muscle twitches, and rigor mortis) of rested Atlantic cod have been established. Since our stress bout showed that this species was not easily excitable, we were less convinced that we actually did study the other extreme, namely, exhausted fish. Nevertheless, the present data from the commercial slaughter of cod suggested that our stress bout was of adequate magnitude to represent potential poor handling routines. Our results consistently showed largely no differences between treatments, and that perimortem handling stress did not cause inferior flesh quality. This suggested that farmed cod can be processed with little risk of reducing product quality (quality index, fillet water content, water-holding capacity, ultimate pH, adenosine triphosphate-related degradation products and K-value, skin and fillet color, water and salt-soluble proteins, hardness, and gaping). For better maintenance of skin appearance after storage, the importance of storing the gutted cod on the belly, avoiding direct contact between skin and crushed ice, is demonstrated. © 2011 Institute of Food Technologists®

  17. Chapter 3. Effects of climate change and commercial fishing on Atlantic cod Gadus morhua.

    PubMed

    Mieszkowska, Nova; Genner, Martin J; Hawkins, Stephen J; Sims, David W

    2009-01-01

    During the course of the last century, populations of Atlantic cod Gadus morhua L. have undergone dramatic declines in abundance across their biogeographic range, leading to debate about the relative roles of climatic warming and overfishing in driving these changes. In this chapter, we describe the geographic distributions of this important predator of North Atlantic ecosystems and document extensive evidence for limitations of spatial movement and local adaptation from population genetic markers and electronic tagging. Taken together, this evidence demonstrates that knowledge of spatial population ecology is critical for evaluating the effects of climate change and commercial harvesting. To explore the possible effects of climate change on cod, we first describe thermal influences on individual physiology, growth, activity and maturation. We then evaluate evidence that temperature has influenced population-level processes including direct effects on recruitment through enhanced growth and activity, and indirect effects through changes to larval food resources. Although thermal regimes clearly define the biogeographic range of the species, and strongly influence many aspects of cod biology, the evidence that population declines across the North Atlantic are strongly linked to fishing activity is now overwhelming. Although there is considerable concern about low spawning stock biomasses, high levels of fishing activity continues in many areas. Even with reduced fishing effort, the potential for recovery from low abundance may be compromised by unfavourable climate and Allee effects. Current stock assessment and management approaches are reviewed, alongside newly advocated methods for monitoring stock status and recovery. However, it remains uncertain whether the rebuilding of cod to historic population sizes and demographic structures will be possible in a warmer North Atlantic.

  18. Rhodopsin gene polymorphism associated with divergent light environments in Atlantic cod.

    PubMed

    Pampoulie, Christophe; Skirnisdottir, Sigurlaug; Star, Bastiaan; Jentoft, Sissel; Jónsdóttir, Ingibjörg G; Hjörleifsson, Einar; Thorsteinsson, Vilhjálmur; Pálsson, Ólafur K; Berg, Paul R; Andersen, Øivind; Magnusdottir, Steinunn; Helyar, Sarah J; Daníelsdóttir, Anna K

    2015-03-01

    The spectral sensitivity of visual pigments in vertebrate eyes is optimized for specific light conditions. One of such pigments, rhodopsin (RH1), mediates dim-light vision. Amino acid replacements at tuning sites may alter spectral sensitivity, providing a mechanism to adapt to ambient light conditions and depth of habitat in fish. Here we present a first investigation of RH1 gene polymorphism among two ecotypes of Atlantic cod in Icelandic waters, which experience divergent light environments throughout the year due to alternative foraging behaviour. We identified one synonymous single nucleotide polymorphism (SNP) in the RH1 protein coding region and one in the 3' untranslated region (3'-UTR) that are strongly divergent between these two ecotypes. Moreover, these polymorphisms coincided with the well-known panthophysin (Pan I) polymorphism that differentiates coastal and frontal (migratory) populations of Atlantic cod. While the RH1 SNPs do not provide direct inference for a specific molecular mechanism, their association with this dim-sensitive pigment indicates the involvement of the visual system in local adaptation of Atlantic cod.

  19. Histone-like proteins from Atlantic cod milt: stimulatory effect on Atlantic salmon leucocytes in vivo and in vitro.

    PubMed

    Pedersen, Guro M; Gildberg, Asbjørn; Steiro, Kari; Olsen, Ragnar L

    2003-03-01

    This study was carried out to reveal some characteristics of cationic proteins from Atlantic cod (Gadus morhua) milt chromatin and to investigate their ability to activate Atlantic salmon (Salmo salar) macrophages. Cationic proteins extracted from cod milt chromatin were fractionated on a cation exchange chromatography column. SDS-PAGE and amino acid analyses of the resulting fractions indicated that these proteins are similar to calf thymus histones. Two cationic protein fractions were used to stimulate leucocytes from Atlantic salmon in vitro and in vivo. Increased production of superoxide, measured as reduction of nitroblue tetrazolium (NBT), was used as indication of macrophage activation. Both fractions induced elevated superoxide anion production in the macrophages after 3 and 6 days of in vitro stimulation. Intraperitoneal injection of the cationic protein fractions in Atlantic salmon (100 mg kg(-1)) four days prior to slaughtering stimulated superoxide production when assayed after one and two days of cell cultivation. In macrophages from fish slaughtered two days after injection, activation could first be seen after two days of cell cultivation.

  20. Evolutionary redesign of the Atlantic cod (Gadus morhua L.) Toll-like receptor repertoire by gene losses and expansions

    PubMed Central

    Solbakken, Monica H.; Tørresen, Ole K.; Nederbragt, Alexander J.; Seppola, Marit; Gregers, Tone F.; Jakobsen, Kjetill S.; Jentoft, Sissel

    2016-01-01

    Genome sequencing of the teleost Atlantic cod demonstrated loss of the Major Histocompatibility Complex (MHC) class II, an extreme gene expansion of MHC class I and gene expansions and losses in the innate pattern recognition receptor (PRR) family of Toll-like receptors (TLR). In a comparative genomic setting, using an improved version of the genome, we characterize PRRs in Atlantic cod with emphasis on TLRs demonstrating the loss of TLR1/6, TLR2 and TLR5 and expansion of TLR7, TLR8, TLR9, TLR22 and TLR25. We find that Atlantic cod TLR expansions are strongly influenced by diversifying selection likely to increase the detectable ligand repertoire through neo- and subfunctionalization. Using RNAseq we find that Atlantic cod TLRs display likely tissue or developmental stage-specific expression patterns. In a broader perspective, a comprehensive vertebrate TLR phylogeny reveals that the Atlantic cod TLR repertoire is extreme with regards to losses and expansions compared to other teleosts. In addition we identify a substantial shift in TLR repertoires following the evolutionary transition from an aquatic vertebrate (fish) to a terrestrial (tetrapod) life style. Collectively, our findings provide new insight into the function and evolution of TLRs in Atlantic cod as well as the evolutionary history of vertebrate innate immunity. PMID:27126702

  1. Evolutionary redesign of the Atlantic cod (Gadus morhua L.) Toll-like receptor repertoire by gene losses and expansions.

    PubMed

    Solbakken, Monica H; Tørresen, Ole K; Nederbragt, Alexander J; Seppola, Marit; Gregers, Tone F; Jakobsen, Kjetill S; Jentoft, Sissel

    2016-04-29

    Genome sequencing of the teleost Atlantic cod demonstrated loss of the Major Histocompatibility Complex (MHC) class II, an extreme gene expansion of MHC class I and gene expansions and losses in the innate pattern recognition receptor (PRR) family of Toll-like receptors (TLR). In a comparative genomic setting, using an improved version of the genome, we characterize PRRs in Atlantic cod with emphasis on TLRs demonstrating the loss of TLR1/6, TLR2 and TLR5 and expansion of TLR7, TLR8, TLR9, TLR22 and TLR25. We find that Atlantic cod TLR expansions are strongly influenced by diversifying selection likely to increase the detectable ligand repertoire through neo- and subfunctionalization. Using RNAseq we find that Atlantic cod TLRs display likely tissue or developmental stage-specific expression patterns. In a broader perspective, a comprehensive vertebrate TLR phylogeny reveals that the Atlantic cod TLR repertoire is extreme with regards to losses and expansions compared to other teleosts. In addition we identify a substantial shift in TLR repertoires following the evolutionary transition from an aquatic vertebrate (fish) to a terrestrial (tetrapod) life style. Collectively, our findings provide new insight into the function and evolution of TLRs in Atlantic cod as well as the evolutionary history of vertebrate innate immunity.

  2. Gene regulation of lipid and phospholipid metabolism in Atlantic cod (Gadus morhua) larvae.

    PubMed

    Li, Keshuai; Østensen, Mari-Ann; Attramadal, Kari; Winge, Per; Sparstad, Torfinn; Bones, Atle M; Vadstein, Olav; Kjørsvik, Elin; Olsen, Yngvar

    2015-12-01

    The mechanism of essentiality of dietary phospholipid (PL) for larval fish is not clear. The main objective of the present study was to determine if the PL requirement of Atlantic cod larvae was due to any genetic impairment caused by functional immaturity. Cod larvae were sampled at 1, 3, 8, 13, 17, 18, 30, 42 and 60 days post hatch (dph) for transcriptome analysis using a recently developed microarray. The fatty acid profile and gene expression levels of cod larvae at 17 dph were compared after feeding differently enriched rotifers, which contained different DHA levels in PL. No significant differences (p<0.05) were found for the two rotifer diets in the overall gene expression level of cod larvae, their growth and survival, and their DHA levels in total lipid and PL fraction. The fatty acid data suggested that dietary EPA was elongated to DPA by cod larvae, and a threshold DHA level in PL to maintain membrane fluidity and other functions may exist. There appeared to be no major effect of development on the expression of key genes of PL biosynthesis suggesting no genetic constrain in early developmental stages. Our overall data suggested that besides the possible limited de novo PC synthesis ability in the intestine, other metabolic constraints should also be considered, especially the possible low input of bile PC as a result of immature liver. Further studies are needed to elucidate the gene expression level and enzyme activity in the PL biosynthesis pathways for specific tissue or cells.

  3. Spawning behavior in Atlantic cod: analysis by use of data storage tags

    USGS Publications Warehouse

    Grabowski, Timothy B.; Thorsteinsson, Vilhjalmur; Marteinsdóttir, Gudrún

    2014-01-01

     Electronic data storage tags (DSTs) were implanted into Atlantic cod captured in Icelandic waters from 2002 to 2007 and the depth profiles recovered from these tags (females: n = 31, males: n = 27) were used to identify patterns consistent with published descriptions of cod courtship and spawning behavior. The individual periods of time that males spent exhibiting behavior consistent with being present in a spawning aggregation—i.e. periods consisting of a clear tidal signature in the DST depth profile associated with an individual remaining on or near the substrate—were longer than those of females. Over the course of a spawning season, male cod spent approximately twice the amount of time in spawning aggregations than females, but female cod visited more aggregations per unit time. On average, males participated in approximately 57% more putative spawning events, i.e. vertical ascents potentially corresponding to gamete release, than did females. However, males <85 cm total length participated in the same number of putative spawning events as females of comparable size. In both sexes, larger individuals and/or individuals that spent a longer period of time within an aggregation participated in a larger number of putative spawning events. Although further validation and refinement is necessary, particularly in the identification of spawning events, the ability offered by DSTs to quantify cod spawning behavior may aid in the development of management and conservation plans.

  4. Highly localized divergence within supergenes in Atlantic cod (Gadus morhua) within the Gulf of Maine.

    PubMed

    Barney, Bryan T; Munkholm, Christiane; Walt, David R; Palumbi, Stephen R

    2017-03-31

    Atlantic cod (Gadus morhua), is known to vary genetically across the North Atlantic, Greenland, and Newfoundland. This genetic variation occurs both spatially and temporally through decades of heavy fishing, and is concentrated in three linkage disequilibrium blocks, previously defined by pedigreed linkage mapping analysis. Variation within these genomic regions is correlated with both seawater temperature and behavioral ecotype. The full extent and nature of these linkage groups is important information for interpreting cod genetic structure as a tool for future fisheries management. We conducted whole genome sequencing for 31 individual cod from three sub-populations in the Gulf of Maine. Across the genome, we found 3,390,654 intermediate to high frequency Single Nucleotide Polymorphisms (SNPs). We show that pairwise linkage analysis among these SNPs is a powerful tool to detect linkage disequilibrium clusters by recovering the three previously detected linkage groups and identifying the 1031 genes contained therein. Across these genes, we found significant population differentiation among spawning groups in the Gulf of Maine and between Georges Bank and Gulf of Maine. Coordinated divergence among these genes and their differentiation at both short and long spatial scales suggests that they are acting as linked supergenes in local adaptation of cod populations. Differentiation between SNPs in linkage disequilibrium blocks is the major signal of genetic differentiation between all groups tested within the Gulf of Maine. Our data provide a map of genes contained in these blocks, allowing an enhanced search for neutral genetic structure for demographic inference and fisheries modeling. Patterns of selection and the history of populations may be possible to identify in cod using this description of linkage disequilibrium blocks and future data sets to robustly separate neutral and selected genetic markers.

  5. A Novel Beta-Defensin Antimicrobial Peptide in Atlantic Cod with Stimulatory Effect on Phagocytic Activity

    PubMed Central

    Ruangsri, Jareeporn; Kitani, Yoichiro; Kiron, Viswanath; Lokesh, Jep; Brinchmann, Monica F.; Karlsen, Bård Ove; Fernandes, Jorge M. O.

    2013-01-01

    A novel defensin antimicrobial peptide gene was identified in Atlantic cod, Gadus morhua. This three exon/two intron defensin gene codes for a peptide precursor consisting of two domains: a signal peptide of 26 amino acids and a mature peptide of 40 residues. The mature cod defensin has six conserved cysteine residues that form 1–5, 2–4 and 3–6 disulphide bridges. This pattern is typical of beta-defensins and this gene was therefore named cod beta-defensin (defb). The tertiary structure of Defb exhibits an α/β fold with one α helix and β1β2β3 sheets. RT-PCR analysis indicated that defb transcripts were present mainly in the swim bladder and peritoneum wall but could also be detected at moderate to low levels in skin, head- and excretory kidneys. In situ hybridisation revealed that defb was specifically expressed by cells located in the swim bladder submucosa and the oocytes. During embryonic development, defb gene transcripts were detectable from the golden eye stage onwards and their expression was restricted to the swim bladder and retina. Defb was differentially expressed in several tissues following antigenic challenge with Vibrio anguillarum, being up-regulated up to 25-fold in head kidney. Recombinant Defb displayed antibacterial activity, with a minimal inhibitory concentration of 0.4–0.8 µM and 25–50 µM against the Gram-(+) bacteria Planococcus citreus and Micrococcus luteus, respectively. In addition, Defb stimulated phagocytic activity of cod head kidney leucocytes in vitro. These findings imply that beta-defensins may play an important role in the innate immune response of Atlantic cod. PMID:23638029

  6. Expression of the oligopeptide transporter, PepT1, in larval Atlantic cod (Gadus morhua).

    PubMed

    Amberg, J J; Myr, C; Kamisaka, Y; Jordal, A-E O; Rust, M B; Hardy, R W; Koedijk, R; Rønnestad, I

    2008-06-01

    The intestinal absorption of di- and tri-peptides generally occurs via the oligopeptide transporter, PepT1. This study evaluates the expression of PepT1 in larval Atlantic cod (Gadus morhua) during the three weeks following the onset of exogenous feeding. Larval Atlantic cod were fed either wild captured zooplankton or enriched rotifers. cDNA was prepared from whole cod larvae preceding first feeding and at 1000 each Tuesday and Thursday for the following three weeks. Spatial and temporal expression patterns of PepT1 mRNA were compared between fish consuming the two prey types using in situ hybridization and quantitative real-time PCR. Results indicated that PepT1 mRNA was expressed prior to the onset of exogenous feeding. In addition, PepT1 was expressed throughout the digestive system except the esophagus and sphincter regions. Expression slightly increased following first-feeding and continued to increase throughout the study for larvae feeding on both prey types. When comparing PepT1 expression in larvae larger than 0.15-mg dry mass with expression levels in larvae prior to feeding, no differences were detected for larvae fed rotifers, but the larvae fed zooplankton had significantly greater PepT1 expression at the larger size. In addition, PepT1 expression in the zooplankton fed larvae larger than 0.15-mg dry mass had significantly greater expression than rotifer fed larvae of a similar weight. Switching prey types did not affect PepT1 expression. These results indicate that Atlantic cod PepT1 expression was slightly different relative to dietary treatment during the three weeks following first-feeding. In addition, PepT1 may play an important role in the larval nutrition since it is widely expressed in the digestive tract.

  7. Effects of ocean acidification on the calcification of otoliths of larval Atlantic cod, Gadus morhua L.

    NASA Astrophysics Data System (ADS)

    Maneja, R. H.; Frommel, A. Y.; Geffen, A. J.; Folkvord, A.; Piatkowski, U.; Chang, M. Y.; Clemmesen, C.

    2012-04-01

    The aragonitic calcium carbonate composition of the otoliths of teleost fishes could bring the organism in direct risk to ocean acidification. The potential effects of increase in atmospheric CO2 on the calcification of the otoliths were investigated by rearing Atlantic cod larvae (Gadus morhua L.) in three pCO2 concentrations, control-370, medium-1800, and high-4200 ppm from March to May 2010. Hypercalcification of otoliths were observed from 7 to 46-dph cod larvae cultured at elevated pCO2 concentrations. The sagittae and lapilli were largest at the high pCO2 treatment followed by medium and control with the biggest difference (83.8%) in mean otolith (sagitta) surface area at 32-dph between the high and control groups. The shift in the growth rates of the sagittae and lapilli also occurred much earlier in the high treatment with the growth of the sagitta surpassing that of the lapillus already at 32-dph. On the other hand, Atlantic cod larvae showed no trends in fluctuating asymmetry of the otoliths vis-a-vis the increase in otolith growth from elevated pCO2.

  8. Cape Cod

    Atmospheric Science Data Center

    2014-05-15

    article title:  Winter in Cape Cod     View Larger Image Cape Cod extends over 50 miles into the Atlantic Ocean. Its rugged coastline, ... February 18, 2001 - Snow and thin clouds over Cape Cod. project:  MISR category:  gallery ...

  9. Plastic ingestion by Atlantic cod (Gadus morhua) from the Norwegian coast.

    PubMed

    Bråte, Inger Lise N; Eidsvoll, David P; Steindal, Calin Constantin; Thomas, Kevin V

    2016-11-15

    This study documents the occurrence of microplastic (<5mm), mesoplastics (5-20mm) and macroplastic (>20mm) in Atlantic cod (Gadus morhua), a common and economically important species of marine fish in Norway. Fish stomachs (n=302) were examined from six different locations along the coast of Norway. Three percent of the individual stomachs contained items identified by Fourier transform infrared spectroscopy (FTIR) as synthetic polymers. Bergen City Harbour was a hotspot with 27% of the cod examined found to contain plastic. Polyester was the most frequently detected polymer. All bar one of the stomachs that contained plastic were full of organic stomach content, suggesting a plastic gut clearance rate similar to the ingested food. It is proposed that stomach fullness is an important metric in order to avoid underestimations when assessing the levels of microplastic ingested by fish.

  10. Factors Regulating Early Life History Dispersal of Atlantic Cod (Gadus morhua) from Coastal Newfoundland

    PubMed Central

    Stanley, Ryan R. E.; deYoung, Brad; Snelgrove, Paul V. R.; Gregory, Robert S.

    2013-01-01

    To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua), we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day−1 with a net mortality of 27%•day–1. Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10–20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic. PMID:24058707

  11. Factors regulating early life history dispersal of Atlantic cod (Gadus morhua) from coastal Newfoundland.

    PubMed

    Stanley, Ryan R E; deYoung, Brad; Snelgrove, Paul V R; Gregory, Robert S

    2013-01-01

    To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua), we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day(-1) with a net mortality of 27%•day(-1). Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10-20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic.

  12. Transcriptome profiling of the antiviral immune response in Atlantic cod macrophages.

    PubMed

    Eslamloo, Khalil; Xue, Xi; Booman, Marije; Smith, Nicole C; Rise, Matthew L

    2016-10-01

    A study was conducted to determine the transcriptome response of Atlantic cod (Gadus morhua) macrophages to the viral mimic, polyriboinosinic polyribocytidylic acid (pIC), using a 20K Atlantic cod microarray platform and qPCR. We identified 285 significantly up-regulated and 161 significantly down-regulated probes in cod macrophages 24 h after pIC stimulation. A subset of 26 microarray-identified transcripts was subjected to qPCR validation using samples treated with pIC or phosphate-buffered saline (control) over time (3, 6, 12, 24, 48 h), and 77% of them showed a significant response to pIC. The microarray and qPCR analyses in this study showed that pIC induced the expression of cod macrophage transcripts involved in RLR- and TLR-dependent pathogen recognition (e.g. tlr3, tlr7, mda5 and lgp2), as well as signal transducers (e.g. stat1 and nfkbia) and transcription activators (e.g. irf7 and irf10) in the MyD88-independent and dependent signalling pathways. Several immune effectors (e.g. isg15s, viperin, herc4, mip2 and ccl13) were significantly up-regulated in pIC-stimulated cod macrophages. The expression of some transcripts (e.g. irf7, irf10, viperin) was significantly up-regulated by pIC as early as 12 h. All pIC-induced transcripts had peak expression at either 24 h (e.g. tlr7, irf7, mip2) or 48 h (e.g. tlr3, lgp2, stat1). This study suggests possible roles of both vertebrate-conserved (e.g. tlr3 as an up-regulated gene) and fish-specific (tlr22g as a down-regulated gene) receptors in dsRNA recognition, and the importance of conserved and potentially fish-specific interferon stimulated genes in cod macrophages.

  13. Recombinant cold-adapted trypsin I from Atlantic cod-expression, purification, and identification.

    PubMed

    Jónsdóttir, Gudrún; Bjarnason, Jón Bragi; Gudmundsdóttir, Agústa

    2004-01-01

    Atlantic cod trypsin I is a cold-adapted proteolytic enzyme exhibiting approximately 20 times higher catalytic efficiency (kcat/KM) than its mesophilic bovine counterpart for the simple amide substrate BAPNA. In general, cold-adapted proteolytic enzymes are sensitive to autolytic degradation, thermal inactivation as well as molecular aggregation, even at temperatures as low as 18-25 degrees C which may explain the problems observed with their expression, activation, and purification. Prior to the data presented here, there have been no reports in the literature on the expression of psychrophilic or cold-adapted proteolytic enzymes from fish. Nevertheless, numerous cold-adapted proteolytic microbial enzymes have been successfully expressed in bacteria and yeast. This report describes successful expression, activation, and purification of the recombinant cod trypsin I in the His-Patch ThioFusion Escherichia coli expression system. The E. coli pThioHis expression vector used in the study enabled the formation of a fusion protein between a highly soluble fraction of HP-thioredoxin contained in the vector and the N-terminal end of the precursor form of cod trypsin I. The HP-thioredoxin part of the fusion protein binds to a metal-chelating ProBond column, which facilitated its purification. The cod trypsin I part of the purified fusion protein was released by proteolytic cleavage, resulting in concomitant activation of the recombinant enzyme. The recombinant cod trypsin I was purified to homogeneity on a trypsin-specific benzamidine affinity column. The identity of the recombinant enzyme was demonstrated by electrophoresis and chromatography.

  14. Low plastic ingestion rate in Atlantic cod (Gadus morhua) from Newfoundland destined for human consumption collected through citizen science methods.

    PubMed

    Liboiron, Max; Liboiron, France; Wells, Emily; Richárd, Natalie; Zahara, Alexander; Mather, Charles; Bradshaw, Hillary; Murichi, Judyannet

    2016-12-15

    Marine microplastics are a contaminant of concern because their small size allows ingestion by a wide range of marine life. Using citizen science during the Newfoundland recreational cod fishery, we sampled 205 Atlantic cod (Gadus morhua) destined for human consumption and found that 5 had eaten plastic, an ingestion prevalence rate of 2.4%. This ingestion rate for Atlantic cod is the second lowest recorded rate in the reviewed published literature (the lowest is 1.4%), and the lowest for any fish in the North Atlantic. This is the first report for plastic ingestion in fish in Newfoundland, Canada, a province dependent on fish for sustenance and livelihoods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Diet affects the redox system in developing Atlantic cod (Gadus morhua) larvae

    PubMed Central

    Penglase, Samuel; Edvardsen, Rolf B.; Furmanek, Tomasz; Rønnestad, Ivar; Karlsen, Ørjan; van der Meeren, Terje; Hamre, Kristin

    2015-01-01

    The growth and development of marine fish larvae fed copepods is superior to those fed rotifers, but the underlying molecular reasons for this are unclear. In the following study we compared the effects of such diets on redox regulation pathways during development of Atlantic cod (Gadus morhua) larvae. Cod larvae were fed a control diet of copepods or the typical rotifer/Artemia diet commonly used in commercial marine fish hatcheries, from first feeding until after metamorphosis. The oxidised and reduced glutathione levels, the redox potential, and the mRNA expression of 100 genes in redox system pathways were then compared between treatments during larval development. We found that rotifer/Artemia-fed cod larvae had lower levels of oxidised glutathione, a more reduced redox potential, and altered expression of approximately half of the redox system genes when compared to copepod-fed larvae. This rotifer/Artemia diet-induced differential regulation of the redox system was greatest during periods of suboptimal growth. Upregulation of the oxidative stress response transcription factor, nrf2, and NRF2 target genes in rotifer/Artemia fed larvae suggest this diet induced an NRF2-mediated oxidative stress response. Overall, the data demonstrate that nutritional intake plays a role in regulating the redox system in developing fish larvae. This may be a factor in dietary-induced differences observed in larval growth. PMID:26099546

  16. Ecological and genetic impact of Atlantic cod larval drift in the Skagerrak

    PubMed Central

    Stenseth, Nils Chr; Jorde, Per Erik; Chan, Kung-Sik; Hansen, Elizabeth; Knutsen, Halvor; André, Carl; Skogen, Morten D; Lekve, Kyrre

    2006-01-01

    We evaluate the hypothesis that Atlantic cod larvae are passively transported by sea currents from off-shore spawning areas to settle in coastal waters, a hypothesis which has recently gained support from genetic analysis of cod in the North Sea–Skagerrak area. Such larval transport has been suggested to be an important mechanism behind the commonly observed low spatial genetic differentiation in many marine organisms. Here, we apply an ARMAX(2,2) model for juvenile abundance and use long-term monitoring data from the Skagerrak coast, constituting 54 continuous annual series from 1945 to 1997. Analysing the model, we find that the product of the size of the North Sea breeding stock and the strength of the net inflow of North Sea waters had a significant, positive effect on the abundance of coastal juvenile cod. The peak effect occurs during the month of March, just after spawning, when eggs and larvae remain pelagic and sensitive to currents. In contrast, we find no evidence of any direct effect of the North Sea spawning stock alone. Our analyses indicate that 15–20 000 0-group larvae from the North Sea reach each fjord per year, on average. This corresponds to about 1–10% of the total 0-group population in each fjord on average. These findings clearly demonstrate a direct link between larval drift and gene flow in the marine environment. PMID:16600885

  17. Isolation and biochemical characterisation of lipid rafts from Atlantic cod (Gadus morhua) intestinal enterocytes.

    PubMed

    Gylfason, Gudjón Andri; Knútsdóttir, Erna; Asgeirsson, Bjarni

    2010-01-01

    Lipid rafts are glycosphingolipid/cholesterol-enriched membrane microdomains that have been extensively studied during the past two decades. Our aim was to isolate and perform biochemical characterization of lipid rafts from the intestinal brush border membrane (BBM) of Atlantic cod (Gadus morhua) to confirm their existence in a cold-water species and compare their characteristics with lipid rafts from other species in terms of lipid and protein content. To validate the isolation process, we assayed marker enzymes for subcellular organelles, including alkaline phosphatase (AP) and leucine aminopeptidase (LAP), both well-known marker enzymes for BBM and lipid rafts. All biochemical methods showed enrichment of AP in both the BBM and lipid raft fractions. Proteomic studies were performed by MALDI-TOF mass spectrometry using trypsin digested SDS-PAGE samples. Various proteins were associated with the cod intestinal lipid raft preparation such as aminopeptidase-N, prohibitin, and beta-actin. Lipid analysis with (31)P NMR and thin layer chromatography on BBMs and lipid rafts samples gave higher content of sphingomyelin than previously reported in the BBM and lower content of phosphatidylcholine. Furthermore, sphingomyelin was highly dominant in the lipid rafts together with cholesterol. The existence of lipid rafts containing previously reported lipid raft characteristics from the cod intestine has, therefore, been confirmed in a ray-finned fish for the first time to the best of our knowledge.

  18. Organization of a β and α globin gene set in the teleost Atlantic cod, Gadus morhua.

    PubMed

    Halldórsdóttir, Katrín; Árnason, Einar

    2009-12-01

    Developmental globin gene expression and gene switching in vertebrates have been extensively studied. Globin gene regions have been characterized in some fish species and show linked α and β loci. Understanding coordinated expression between α and β globin genes in fish is of importance for further insights into globin gene regulation in teleosts and higher vertebrates. We characterize linked β and α globin genes in Atlantic cod, pulled from the Atlantic cod genome with a PCR research strategy, by screening a genomic λ library and primer walking. The genes are oriented tail-to-head (5'-3'), differing from the head-to-head orientation in transcriptional polarity characteristic of teleostean globin genes. Four tandem repeats are found in an intergenic region of 1500 base pairs. One microsatellite, which consists primarily of atg tandem repeats, has an open reading frame. The globin genes and open reading frame have a CCAAT promoter element and TATA boxes. The promoters of the open reading frame and the β gene share an 89-bp block (with 100% identity) that probably regulates transcription.

  19. Thermal growth potential of Atlantic cod by the end of the 21st century.

    PubMed

    Butzin, Martin; Pörtner, Hans-Otto

    2016-12-01

    Ocean warming may lead to smaller body sizes of marine ectotherms, because metabolic rates increase exponentially with temperature while the capacity of the cardiorespiratory system to match enhanced oxygen demands is limited. Here, we explore the impact of rising sea water temperatures on Atlantic cod (Gadus morhua), an economically important fish species. We focus on changes in the temperature-dependent growth potential by a transfer function model combining growth observations with climate model ensemble temperatures. Growth potential is expressed in terms of asymptotic body weight and depends on water temperature. We consider changes between the periods 1985-2004 and 2081-2100, assuming that future sea water temperatures will evolve according to climate projections for IPCC AR5 scenario RCP8.5. Our model projects a response of Atlantic cod to future warming, differentiated according to ocean regions, leading to increases of asymptotic weight in the Barents Sea, while weights are projected to decline at the southern margin of the biogeographic range. Southern spawning areas will disappear due to thermal limitation of spawning stages. These projections match the currently observed biogeographic shifts and the temperature- and oxygen-dependent decline in routine aerobic scope at southern distribution limits. © 2016 John Wiley & Sons Ltd.

  20. Substantial Downregulation of Myogenic Transcripts in Skeletal Muscle of Atlantic Cod during the Spawning Period

    PubMed Central

    Edvardsen, Vigdis

    2016-01-01

    Gonadal maturation is an extremely energy consuming process for batch spawners and it is associated with a significant decrease in growth and seasonal deterioration in flesh quality. Our knowledge about the molecular mechanisms linking sexual maturation and muscle growth is still limited. In the present study, we performed RNA-Seq using 454 GS-FLX pyrosequencing in fast skeletal muscle sampled from two-year-old Atlantic cod (Gadus morhua) at representative time points throughout the reproductive cycle (August, March and May). In total, 126,937 good quality reads were obtained, with 546 nucleotide length and 52% GC content on average. RNA-Seq analysis using the CLC Genomics Workbench with the Atlantic cod reference UniGene cDNA data revealed 59,581 (46.9%) uniquely annotated reads. Pairwise comparison for expression levels identified 153 differentially expressed UniGenes between time points. Notably, we found a significant suppression of myh13 and myofibrillar gene isoforms in fast skeletal muscle during the spawning season. This study uncovered a large number of differentially expressed genes that may be influenced by gonadal maturation, thus representing a significant contribution to our limited understanding of the molecular mechanisms regulating muscle wasting and regeneration in batch spawners during their reproductive cycle. PMID:26844771

  1. The immune response of juvenile Atlantic cod (Gadus morhua L.) to chronic exposure to produced water.

    PubMed

    Pérez-Casanova, Juan C; Hamoutene, Dounia; Samuelson, Stephanie; Burt, Kimberly; King, Thomas L; Lee, Kenneth

    2010-07-01

    Produced water (PW) is the main discharge from the offshore oil industry and contains oil-derived compounds such as poly-aromatic hydrocarbons, phenols, alkylphenols, and heavy metals. Studies suggest that PW discharges may affect the biota over larger areas from the oil drilling sites at sea than originally predicted. We investigated the effects of chronic exposure to PW on some aspects of juvenile Atlantic cod immunity, stress response and growth by intermittently exposing fish to 0, 100 or 200 ppm of PW for 22 weeks. No significant effects of PW were observed on growth, hepatosomatic index, condition factor or plasma cortisol. The respiratory burst (RB) of circulating leukocytes was significantly elevated in the 100 ppm group only, while the RB of head-kidney leukocytes was significantly decreased in both the 100 and 200 ppm groups. Significant up-regulation of the mRNA expression of beta-2-microglobulin, immunoglobulin-M light chain and interleukins-1beta and -8 was observed in the 200 ppm group, while the down-regulation of interferon stimulated gene 15 was obvious for both the 100 and 200 ppm groups. The results suggest that chronic exposure to environmentally relevant concentrations of PW causes modulations of the immune system of juvenile Atlantic cod with most immune parameters being stimulated, potentially resulting in an energetic cost that may be detrimental to the fish. Crown Copyright 2010. Published by Elsevier Ltd. All rights reserved.

  2. Haemoglobin polymorphisms affect the oxygen-binding properties in Atlantic cod populations.

    PubMed

    Andersen, Oivind; Wetten, Ola Frang; De Rosa, Maria Cristina; Andre, Carl; Carelli Alinovi, Cristiana; Colafranceschi, Mauro; Brix, Ole; Colosimo, Alfredo

    2009-03-07

    A major challenge in evolutionary biology is to identify the genes underlying adaptation. The oxygen-transporting haemoglobins directly link external conditions with metabolic needs and therefore represent a unique system for studying environmental effects on molecular evolution. We have discovered two haemoglobin polymorphisms in Atlantic cod populations inhabiting varying temperature and oxygen regimes in the North Atlantic. Three-dimensional modelling of the tetrameric haemoglobin structure demonstrated that the two amino acid replacements Met55beta1Val and Lys62beta1Ala are located at crucial positions of the alpha1beta1 subunit interface and haem pocket, respectively. The replacements are proposed to affect the oxygen-binding properties by modifying the haemoglobin quaternary structure and electrostatic feature. Intriguingly, the same molecular mechanism for facilitating oxygen binding is found in avian species adapted to high altitudes, illustrating convergent evolution in water- and air-breathing vertebrates to reduction in environmental oxygen availability. Cod populations inhabiting the cold Arctic waters and the low-oxygen Baltic Sea seem well adapted to these conditions by possessing the high oxygen affinity Val55-Ala62 haplotype, while the temperature-insensitive Met55-Lys62 haplotype predominates in the southern populations. The distinct distributions of the functionally different haemoglobin variants indicate that the present biogeography of this ecologically and economically important species might be seriously affected by global warming.

  3. Antibiotic uptake by cultured Atlantic cod leucocytes and effect on intracellular Francisella noatunensis subsp. noatunensis replication.

    PubMed

    Kaldestad, Marte; Haugland, Gyri T; Rønneseth, Anita; Wergeland, Heidrun I; Samuelsen, Ole Bent

    2014-02-04

    The granuloma disease caused by Francisella noatunensis subsp. noatunensis in farmed Atlantic cod has not been successfully treated by use of antibacterials, even when antibacterial resistance testing indicates a sufficient effect. The reason for this treatment failure may be the intracellular existence of the bacteria within immune cells, mainly macrophages. To investigate the effect of antibacterials on intracellular Francisella replication, we established a protocol for the detection of drugs within Atlantic cod immune cells using high-performance liquid chromatography (HPLC). When the uptake and intracellular concentrations of oxolinic acid and flumequine were analysed in isolated adherent head kidney leucocytes (HKLs) by HPLC, we found that uptake was rapid and the intracellular concentrations reflected the extracellular exposure concentrations. To investigate the effect of the antibacterial compounds on intracellular bacterial replication, adherent HKLs experimentally infected with the bacteria were analysed using flow cytometry and intracellular labelling of bacteria by specific antibodies. We found that flumequine did not inhibit intracellular bacterial replication. Unexpectedly, the results indicated that the intracellularly effiacy of the drug was reduced. The HPLC method used proved to be highly applicable for accurate determination of intracellular drug concentrations. When combined with sensitive and specific flow cytometry analyses for identification and measurement of intracellular bacterial replication, we suggest that this approach can be very valuable for the design of antibacterial treatments of intracellular pathogens.

  4. Haemoglobin polymorphisms affect the oxygen-binding properties in Atlantic cod populations

    PubMed Central

    Andersen, Øivind; Wetten, Ola Frang; De Rosa, Maria Cristina; Andre, Carl; Carelli Alinovi, Cristiana; Colafranceschi, Mauro; Brix, Ole; Colosimo, Alfredo

    2008-01-01

    A major challenge in evolutionary biology is to identify the genes underlying adaptation. The oxygen-transporting haemoglobins directly link external conditions with metabolic needs and therefore represent a unique system for studying environmental effects on molecular evolution. We have discovered two haemoglobin polymorphisms in Atlantic cod populations inhabiting varying temperature and oxygen regimes in the North Atlantic. Three-dimensional modelling of the tetrameric haemoglobin structure demonstrated that the two amino acid replacements Met55β1Val and Lys62β1Ala are located at crucial positions of the α1β1 subunit interface and haem pocket, respectively. The replacements are proposed to affect the oxygen-binding properties by modifying the haemoglobin quaternary structure and electrostatic feature. Intriguingly, the same molecular mechanism for facilitating oxygen binding is found in avian species adapted to high altitudes, illustrating convergent evolution in water- and air-breathing vertebrates to reduction in environmental oxygen availability. Cod populations inhabiting the cold Arctic waters and the low-oxygen Baltic Sea seem well adapted to these conditions by possessing the high oxygen affinity Val55–Ala62 haplotype, while the temperature-insensitive Met55–Lys62 haplotype predominates in the southern populations. The distinct distributions of the functionally different haemoglobin variants indicate that the present biogeography of this ecologically and economically important species might be seriously affected by global warming. PMID:19033139

  5. Trans-species polymorphism at antimicrobial innate immunity cathelicidin genes of Atlantic cod and related species.

    PubMed

    Halldórsdóttir, Katrín; Árnason, Einar

    2015-01-01

    Natural selection, the most important force in evolution, comes in three forms. Negative purifying selection removes deleterious variation and maintains adaptations. Positive directional selection fixes beneficial variants, producing new adaptations. Balancing selection maintains variation in a population. Important mechanisms of balancing selection include heterozygote advantage, frequency-dependent advantage of rarity, and local and fluctuating episodic selection. A rare pathogen gains an advantage because host defenses are predominantly effective against prevalent types. Similarly, a rare immune variant gives its host an advantage because the prevalent pathogens cannot escape the host's apostatic defense. Due to the stochastic nature of evolution, neutral variation may accumulate on genealogical branches, but trans-species polymorphisms are rare under neutrality and are strong evidence for balancing selection. Balanced polymorphism maintains diversity at the major histocompatibility complex (MHC) in vertebrates. The Atlantic cod is missing genes for both MHC-II and CD4, vital parts of the adaptive immune system. Nevertheless, cod are healthy in their ecological niche, maintaining large populations that support major commercial fisheries. Innate immunity is of interest from an evolutionary perspective, particularly in taxa lacking adaptive immunity. Here, we analyze extensive amino acid and nucleotide polymorphisms of the cathelicidin gene family in Atlantic cod and closely related taxa. There are three major clusters, Cath1, Cath2, and Cath3, that we consider to be paralogous genes. There is extensive nucleotide and amino acid allelic variation between and within clusters. The major feature of the results is that the variation clusters by alleles and not by species in phylogenetic trees and discriminant analysis of principal components. Variation within the three groups shows trans-species polymorphism that is older than speciation and that is suggestive of

  6. Constant proportion harvest policies: dynamic implications in the Pacific halibut and Atlantic cod fisheries.

    PubMed

    Yakubu, Abdul-Aziz; Li, Nianpeng; Conrad, Jon M; Zeeman, Mary-Lou

    2011-07-01

    Overfishing, pollution and other environmental factors have greatly reduced commercially valuable stocks of fish. In a 2006 Science article, a group of ecologists and economists warned that the world may run out of seafood from natural stocks if overfishing continues at current rates. In this paper, we explore the interaction between a constant proportion harvest policy and recruitment dynamics. We examine the discrete-time constant proportion harvest policy discussed in Ang et al. (2009) and then expand the framework to include stock-recruitment functions that are compensatory and overcompensatory, both with and without the Allee effect. We focus on constant proportion policies (CPPs). CPPs have the potential to stabilize complex overcompensatory stock dynamics, with or without the Allee effect, provided the rates of harvest stay below a threshold. If that threshold is exceeded, CPPs are known to result in the sudden collapse of a fish stock when stock recruitment exhibits the Allee effect. In case studies, we analyze CPPs as they might be applied to Gulf of Alaska Pacific halibut fishery and the Georges Bank Atlantic cod fishery based on harvest rates from 1975 to 2007. The best fit models suggest that, under high fishing mortalities, the halibut fishery is vulnerable to sudden population collapse while the cod fishery is vulnerable to steady decline to zero. The models also suggest that CPP with mean harvesting levels from the last 30 years can be effective at preventing collapse in the halibut fishery, but these same policies would lead to steady decline to zero in the Atlantic cod fishery. We observe that the likelihood of collapse in both fisheries increases with increased stochasticity (for example, weather variability) as predicted by models of global climate change.

  7. Juvenile Atlantic cod behavior appears robust to near-future CO2 levels.

    PubMed

    Jutfelt, Fredrik; Hedgärde, Maria

    2015-01-01

    Ocean acidification caused by the anthropogenic release of CO2 is considered a major threat to marine ecosystems. One unexpected impact of elevated water CO2 levels is that behavioral alterations may occur in tropical reef fish and certain temperate fish species. These effects appear to alter many different types of sensory and cognitive functions; if widespread and persistent, they have the potential to cause ecosystem changes. We investigated whether economically and ecologically important Atlantic cod also display behavioral abnormalities by exposing 52 juvenile cod to control conditions (500 μatm, duplicate tanks) or an end-of-the-century ocean acidification scenario (1000 μatm, duplicate tanks) for one month, during which time the fish were examined for a range of behaviors that have been reported to be affected by elevated CO2 in other fish. The behaviors were swimming activity, as measured by number of lines crossed per minute, the emergence from shelter, determined by how long it took the fish to exit a shelter after a disturbance, relative lateralization (a measure of behavioral turning side preference), and absolute lateralization (the strength of behavioral symmetry). We found no effect of CO2 treatment on any of the four behaviors tested: activity (F = 1.61, p = 0.33), emergence from shelter (F = 0.13, p = 0.76), relative lateralization (F = 2.82, p = 0.50), and absolute lateralization (F = 0.80, p = 0.26). Our results indicate that the behavior of Atlantic cod could be resilient to the impacts of near-future levels of water CO2.

  8. Forecasting future recruitment success for Atlantic cod in the warming and acidifying Barents Sea.

    PubMed

    Koenigstein, Stefan; Dahlke, Flemming T; Stiasny, Martina H; Storch, Daniela; Clemmesen, Catriona; Pörtner, Hans-Otto

    2017-07-29

    Productivity of marine fish stocks is known to be affected by environmental and ecological drivers, and global climate change is anticipated to alter recruitment success of many stocks. While the direct effects of environmental drivers on fish early life stage survival can be quantified experimentally, indirect effects in marine ecosystems and the role of adaptation are still highly uncertain. We developed an integrative model for the effects of ocean warming and acidification on the early life stages of Atlantic cod in the Barents Sea, termed SCREI (Simulator of Cod Recruitment under Environmental Influences). Experimental results on temperature and CO2 effects on egg fertilization, egg and larval survival and development times are incorporated. Calibration using empirical time series of egg production, temperature, food and predator abundance reproduces age-0 recruitment over three decades. We project trajectories of recruitment success under different scenarios and quantify confidence limits based on variation in experiments. A publicly accessible web version of the SCREI model can be run under www.oceanchange.uni-bremen.de/;SCREI. Severe reductions in average age-0 recruitment success of Barents Sea cod are projected under uncompensated warming and acidification toward the middle to end of this century. Although high population stochasticity was found, considerable rates of evolutionary adaptation to acidification and shifts in organismal thermal windows would be needed to buffer impacts on recruitment. While increases in food availability may mitigate short-term impacts, an increase in egg production achieved by stock management could provide more long-term safety for cod recruitment success. The SCREI model provides a novel integration of multiple driver effects in different life stages and enables an estimation of uncertainty associated with interindividual and ecological variation. The model thus helps to advance toward an improved empirical foundation for

  9. Evaluating SNP ascertainment bias and its impact on population assignment in Atlantic cod, Gadus morhua.

    PubMed

    Bradbury, Ian R; Hubert, Sophie; Higgins, Brent; Bowman, Sharen; Paterson, Ian G; Snelgrove, Paul V R; Morris, Corey J; Gregory, Robert S; Hardie, David C; Borza, Tudor; Bentzen, Paul

    2011-03-01

    The increasing use of single nucleotide polymorphisms (SNPs) in studies of nonmodel organisms accentuates the need to evaluate the influence of ascertainment bias on accurate ecological or evolutionary inference. Using a panel of 1641 expressed sequence tag-derived SNPs developed for northwest Atlantic cod (Gadus morhua), we examined the influence of ascertainment bias and its potential impact on assignment of individuals to populations ranging widely in origin. We hypothesized that reductions in assignment success would be associated with lower diversity in geographical regions outside the location of ascertainment. Individuals were genotyped from 13 locations spanning much of the contemporary range of Atlantic cod. Diversity, measured as average sample heterozygosity and number of polymorphic loci, declined (c. 30%) from the western (H(e) = 0.36) to eastern (H(e) = 0.25) Atlantic, consistent with a signal of ascertainment bias. Assignment success was examined separately for pools of loci representing differing degrees of reductions in diversity. SNPs displaying the largest declines in diversity produced the most accurate assignment in the ascertainment region (c. 83%) and the lowest levels of correct assignment outside the ascertainment region (c. 31%). Interestingly, several isolated locations showed no effect of assignment bias and consistently displayed 100% correct assignment. Contrary to expectations, estimates of accurate assignment range-wide using all loci displayed remarkable similarity despite reductions in diversity. Our results support the use of large SNP panels in assignment studies of high geneflow marine species. However, our evidence of significant reductions in assignment success using some pools of loci suggests that ascertainment bias may influence assignment results and should be evaluated in large-scale assignment studies. © 2011 Blackwell Publishing Ltd.

  10. Effects of North Sea oil and alkylphenols on biomarker responses in juvenile Atlantic cod (Gadus morhua).

    PubMed

    Sturve, Joachim; Hasselberg, Linda; Fälth, Herman; Celander, Malin; Förlin, Lars

    2006-06-01

    A consequence of oil drilling at sea is the release of produced water contaminated with e.g. polycyclic aromatic hydrocarbons (PAH) and alkylphenols. In the present study, juvenile Atlantic cod were exposed to North Sea oil, nonylphenol and a combination of the North Sea oil and an alkylphenol mixture in a flow-through system. A suite of hepatic biomarkers were analysed. Exposure to North Sea oil resulted in strong induction of CYP1A protein levels and EROD activities. Exposure to nonylphenol, on the other hand, resulted in decreased CYP1A levels and EROD activities. Thus, nonylphenol appears to down-regulate CYP1A expression in Atlantic cod. Combined exposure to North Sea oil with an alkylphenol mixture resulted in lower EROD induction, compared to that in fish exposed to North Sea oil alone. This difference was not statistically significant, but still we believe that the alkylphenols have inhibited CYP1A activities in the fish which may have compromised CYP1A mediated metabolism of other xenobiotics, including PAH. CYP3A protein levels were lower, compared to controls, in fish exposed to nonylphenol and the combination of North Sea oil and alkylphenol mixture. In contrast, the oil alone had no effect on CYP3A protein content. North Sea oil exposure, alone or in combination with alkylphenols, caused oxidative stress observed as elevated levels of GSSG content and GR and CAT activities. Interestingly, exposure to nonylphenol resulted in a marked depletion of total glutathione levels. This apparent depletion may be a consequence of increased conjugation of glutathione to nonylphenol followed by excretion. An increase in conjugation enzyme GST activity was observed in the nonylphenol exposed group, although the difference was not significant. No sign of oxidative damage, measured as lipid peroxidation, was observed in any of the exposures experiments. This study suggests that North Sea oil may lead to oxidative stress and altered CYP1A and CYP3A expression

  11. Residency, site fidelity and habitat use of Atlantic cod (Gadus morhua) at an offshore wind farm using acoustic telemetry.

    PubMed

    Reubens, Jan T; Pasotti, Francesca; Degraer, Steven; Vincx, Magda

    2013-09-01

    Because offshore wind energy development is fast growing in Europe it is important to investigate the changes in the marine environment and how these may influence local biodiversity and ecosystem functioning. One of the species affected by these ecosystem changes is Atlantic cod (Gadus morhua), a heavily exploited, commercially important fish species. In this research we investigated the residency, site fidelity and habitat use of Atlantic cod on a temporal scale at windmill artificial reefs in the Belgian part of the North Sea. Acoustic telemetry was used and the Vemco VR2W position system was deployed to quantify the movement behaviour. In total, 22 Atlantic cod were tagged and monitored for up to one year. Many fish were present near the artificial reefs during summer and autumn, and demonstrated strong residency and high individual detection rates. When present within the study area, Atlantic cod also showed distinct habitat selectivity. We identified aggregation near the artificial hard substrates of the wind turbines. In addition, a clear seasonal pattern in presence was observed. The high number of fish present in summer and autumn alternated with a period of very low densities during the winter period.

  12. Composition and structure of the parasite faunas of cod, Gadus morhua L. (Teleostei: Gadidae), in the North East Atlantic

    PubMed Central

    Perdiguero-Alonso, Diana; Montero, Francisco E; Raga, Juan Antonio; Kostadinova, Aneta

    2008-01-01

    Background Although numerous studies on parasites of the Atlantic cod, Gadus morhua L. have been conducted in the North Atlantic, comparative analyses on local cod parasite faunas are virtually lacking. The present study is based on examination of large samples of cod from six geographical areas of the North East Atlantic which yielded abundant baseline data on parasite distribution and abundance. Materials and Methods A total of 826 fish was sampled in the Baltic, Celtic, Irish and North seas, Icelandic waters and Trondheimsfjord (Norway) in 2002 (spring and autumn) and 2003 (spring). The gills and internal organs (oesophagus, stomach, intestine, pyloric caeca, liver, heart, spleen, gall bladder and gonads) were examined for macroparasites following a standardised protocol. The taxonomic consistency of the identification was ensured thorough the entire study. Results We discuss some problems in parasite identification, outline the composition of the parasite faunas in cod in the six North East Atlantic regions, provide novel data on parasite prevalence and abundance and a comparative assessment of the structure of the regional parasite faunas with respect to the higher-level taxonomic groupings, host specificity and zoogeographical distribution of the parasites. Altogether 57 different parasite forms were found including seven new host records (Diclidophora merlangi, Rhipidocotyle sp., Fellodistomum sp., Steringotrema sp., Cucullanus sp., Spinitectus sp., and Chondracanthus ornatus). The predominant groups of cod parasites were trematodes (19 species) and nematodes (13 species) including larval anisakids which comprised 58.2% of the total number of individuals. Conclusion Our study reveals relatively rich regional parasite faunas in cod from the North East Atlantic which are dominated by generalist parasites with Arcto-Boreal distribution. Further, it provides more detailed data on the distribution in the North East Atlantic of the majority of cod parasites which

  13. Climate warming causes life-history evolution in a model for Atlantic cod (Gadus morhua).

    PubMed

    Holt, Rebecca E; Jørgensen, Christian

    2014-01-01

    Climate change influences the marine environment, with ocean warming being the foremost driving factor governing changes in the physiology and ecology of fish. At the individual level, increasing temperature influences bioenergetics and numerous physiological and life-history processes, which have consequences for the population level and beyond. We provide a state-dependent energy allocation model that predicts temperature-induced adaptations for life histories and behaviour for the North-East Arctic stock (NEA) of Atlantic cod (Gadus morhua) in response to climate warming. The key constraint is temperature-dependent respiratory physiology, and the model includes a number of trade-offs that reflect key physiological and ecological processes. Dynamic programming is used to find an evolutionarily optimal strategy of foraging and energy allocation that maximizes expected lifetime reproductive output given constraints from physiology and ecology. The optimal strategy is then simulated in a population, where survival, foraging behaviour, growth, maturation and reproduction emerge. Using current forcing, the model reproduces patterns of growth, size-at-age, maturation, gonad production and natural mortality for NEA cod. The predicted climate responses are positive for this stock; under a 2°C warming, the model predicted increased growth rates and a larger asymptotic size. Maturation age was unaffected, but gonad weight was predicted to more than double. Predictions for a wider range of temperatures, from 2 to 7°C, show that temperature responses were gradual; fish were predicted to grow faster and increase reproductive investment at higher temperatures. An emergent pattern of higher risk acceptance and increased foraging behaviour was also predicted. Our results provide important insight into the effects of climate warming on NEA cod by revealing the underlying mechanisms and drivers of change. We show how temperature-induced adaptations of behaviour and several life

  14. Climate warming causes life-history evolution in a model for Atlantic cod (Gadus morhua)

    PubMed Central

    Holt, Rebecca E.; Jørgensen, Christian

    2014-01-01

    Climate change influences the marine environment, with ocean warming being the foremost driving factor governing changes in the physiology and ecology of fish. At the individual level, increasing temperature influences bioenergetics and numerous physiological and life-history processes, which have consequences for the population level and beyond. We provide a state-dependent energy allocation model that predicts temperature-induced adaptations for life histories and behaviour for the North-East Arctic stock (NEA) of Atlantic cod (Gadus morhua) in response to climate warming. The key constraint is temperature-dependent respiratory physiology, and the model includes a number of trade-offs that reflect key physiological and ecological processes. Dynamic programming is used to find an evolutionarily optimal strategy of foraging and energy allocation that maximizes expected lifetime reproductive output given constraints from physiology and ecology. The optimal strategy is then simulated in a population, where survival, foraging behaviour, growth, maturation and reproduction emerge. Using current forcing, the model reproduces patterns of growth, size-at-age, maturation, gonad production and natural mortality for NEA cod. The predicted climate responses are positive for this stock; under a 2°C warming, the model predicted increased growth rates and a larger asymptotic size. Maturation age was unaffected, but gonad weight was predicted to more than double. Predictions for a wider range of temperatures, from 2 to 7°C, show that temperature responses were gradual; fish were predicted to grow faster and increase reproductive investment at higher temperatures. An emergent pattern of higher risk acceptance and increased foraging behaviour was also predicted. Our results provide important insight into the effects of climate warming on NEA cod by revealing the underlying mechanisms and drivers of change. We show how temperature-induced adaptations of behaviour and several life

  15. Ocean Acidification Effects on Atlantic Cod Larval Survival and Recruitment to the Fished Population

    PubMed Central

    Stiasny, Martina H.; Mittermayer, Felix H.; Sswat, Michael; Voss, Rüdiger; Jutfelt, Fredrik; Chierici, Melissa; Puvanendran, Velmurugu; Mortensen, Atle; Reusch, Thorsten B. H.; Clemmesen, Catriona

    2016-01-01

    How fisheries will be impacted by climate change is far from understood. While some fish populations may be able to escape global warming via range shifts, they cannot escape ocean acidification (OA), an inevitable consequence of the dissolution of anthropogenic carbon dioxide (CO2) emissions in marine waters. How ocean acidification affects population dynamics of commercially important fish species is critical for adapting management practices of exploited fish populations. Ocean acidification has been shown to impair fish larvae’s sensory abilities, affect the morphology of otoliths, cause tissue damage and cause behavioural changes. Here, we obtain first experimental mortality estimates for Atlantic cod larvae under OA and incorporate these effects into recruitment models. End-of-century levels of ocean acidification (~1100 μatm according to the IPCC RCP 8.5) resulted in a doubling of daily mortality rates compared to present-day CO2 concentrations during the first 25 days post hatching (dph), a critical phase for population recruitment. These results were consistent under different feeding regimes, stocking densities and in two cod populations (Western Baltic and Barents Sea stock). When mortality data were included into Ricker-type stock-recruitment models, recruitment was reduced to an average of 8 and 24% of current recruitment for the two populations, respectively. Our results highlight the importance of including vulnerable early life stages when addressing effects of climate change on fish stocks. PMID:27551924

  16. Ocean Acidification Effects on Atlantic Cod Larval Survival and Recruitment to the Fished Population.

    PubMed

    Stiasny, Martina H; Mittermayer, Felix H; Sswat, Michael; Voss, Rüdiger; Jutfelt, Fredrik; Chierici, Melissa; Puvanendran, Velmurugu; Mortensen, Atle; Reusch, Thorsten B H; Clemmesen, Catriona

    2016-01-01

    How fisheries will be impacted by climate change is far from understood. While some fish populations may be able to escape global warming via range shifts, they cannot escape ocean acidification (OA), an inevitable consequence of the dissolution of anthropogenic carbon dioxide (CO2) emissions in marine waters. How ocean acidification affects population dynamics of commercially important fish species is critical for adapting management practices of exploited fish populations. Ocean acidification has been shown to impair fish larvae's sensory abilities, affect the morphology of otoliths, cause tissue damage and cause behavioural changes. Here, we obtain first experimental mortality estimates for Atlantic cod larvae under OA and incorporate these effects into recruitment models. End-of-century levels of ocean acidification (~1100 μatm according to the IPCC RCP 8.5) resulted in a doubling of daily mortality rates compared to present-day CO2 concentrations during the first 25 days post hatching (dph), a critical phase for population recruitment. These results were consistent under different feeding regimes, stocking densities and in two cod populations (Western Baltic and Barents Sea stock). When mortality data were included into Ricker-type stock-recruitment models, recruitment was reduced to an average of 8 and 24% of current recruitment for the two populations, respectively. Our results highlight the importance of including vulnerable early life stages when addressing effects of climate change on fish stocks.

  17. Correlations of age and growth rate with microbiota composition in Atlantic cod (Gadus morhua) larvae.

    PubMed

    Trinh, Ly T T; Bakke, Ingrid; Vadstein, Olav

    2017-08-17

    Little information is available on the link between host development (growth rate and ontogeny) and the composition of the microbiota in fish larvae. This study was carried out to examine potential correlations of microbiota composition with age and growth rate of Atlantic cod larvae. Small and large cod larvae of the same age, representing slow and fast growing individuals, were sampled 10 times during a period of 42 days post hatching (dph), and the composition of the larval microbiota was investigated using a PCR/DGGE (Denaturing Gradient Gel Electrophoresis) strategy. We found significant differences in the intestinal microbiota of small and large larvae of the same age for 4 of the 10 age stages studied. We further found that the variation in the composition of the larval microbiota was more strongly correlated to age than to growth rate for larvae up to 28 dph, whereas for the older larvae growth rate and age was equally correlated to the composition of the microbiota. These results indicate that larval development may structure the microbiota through a change in selection pressure due to host-microbe and microbe-microbe interactions, and that the composition of the microbiota may influence larval development through improved energy gain.

  18. Harvest selection on Atlantic cod behavioral traits: implications for spatial management

    PubMed Central

    Olsen, Esben Moland; Heupel, Michelle R; Simpfendorfer, Colin A; Moland, Even

    2012-01-01

    Harvesting wild populations may contrast or reinforce natural agents of selection and potentially cause evolutionary changes in life-history traits such as growth and maturation. Harvest selection may also act on behavioral traits, although this field of research has so far received less attention. We used acoustic tags and a network of receivers to monitor the behavior and fate of individual Atlantic cod (Gadus morhua, N = 60) in their natural habitat on the Norwegian Skagerrak coast. Fish with a strong diel vertical migration, alternating between shallow- and deep-water habitats, had a higher risk of being captured in the fishery (traps, gillnet, hand line) as compared to fish that stayed in deeper water. There was also a significant negative correlation between fish size (30–66 cm) and the magnitude of diel vertical migration. Natural selection on behavior was less clear, but tended to favor fish with a large activity space. On a monthly time scale we found significant repeatabilities for cod behavior, meaning that individual characteristics tended to persist and therefore may be termed personality traits. We argue that an evolutionary approach to fisheries management should consider fish behavior. This would be of particular relevance for spatial management actions such as marine reserve design. PMID:22957161

  19. Chitosan as an edible invisible film for quality preservation of herring and atlantic cod.

    PubMed

    Jeon, You-Jin; Kamil, Janak Y V A; Shahidi, Fereidoon

    2002-08-28

    The effect of chitosan with different molecular weights as coatings for shelf-life extension of fresh fillets of Atlantic cod (Gadus morhua) and herring (Clupea harengus) was evaluated over a 12-day storage at refrigerated temperature (4 +/- 1 degrees C). Three chitosan preparations from snow crab (Chinoecetes opilio) processing wastes, differing in viscosities and molecular weights, were prepared; their apparent viscosities (360, 57, and 14 cP) depended on the deacetylation time (4, 10, and 20 h, respectively) of the chitin precursor. Upon coating with chitosans, a significant (p < or = 0.05) reduction in relative moisture losses of 37, 29, 29, 40, and 32% was observed for cod samples coated with 360 cP chitosan after 4, 6, 8, 10, and 12 days of storage, respectively. Chitosan coating significantly (p < or = 0.05) reduced lipid oxidation as displayed in peroxide value, conjugated dienes, 2-thiobarbituric acid reactive substances and headspace volatiles, chemical spoilage as reflected in total volatile basic nitrogen, trimethylamine, and hypoxanthine, and growth of microorganisms as reflected in total plate count in both fish model systems compared to uncoated samples. The preservative efficacy and the viscosity of chitosan were inter-related; the efficacy of chitosans with viscosities of 57 and 360 cP was superior to that of chitosan with a 14 cP viscosity. Thus, chitosan as edible coating would enhance the quality of seafoods during storage.

  20. Spatiotemporal SNP analysis reveals pronounced biocomplexity at the northern range margin of Atlantic cod Gadus morhua

    PubMed Central

    Therkildsen, Nina Overgaard; Hemmer-Hansen, Jakob; Hedeholm, Rasmus Berg; Wisz, Mary S; Pampoulie, Christophe; Meldrup, Dorte; Bonanomi, Sara; Retzel, Anja; Olsen, Steffen Malskær; Nielsen, Einar Eg

    2013-01-01

    Accurate prediction of species distribution shifts in the face of climate change requires a sound understanding of population diversity and local adaptations. Previous modeling has suggested that global warming will lead to increased abundance of Atlantic cod (Gadus morhua) in the ocean around Greenland, but the dynamics of earlier abundance fluctuations are not well understood. We applied a retrospective spatiotemporal population genomics approach to examine the temporal stability of cod population structure in this region and to search for signatures of divergent selection over a 78-year period spanning major demographic changes. Analyzing >900 gene-associated single nucleotide polymorphisms in 847 individuals, we identified four genetically distinct groups that exhibited varying spatial distributions with considerable overlap and mixture. The genetic composition had remained stable over decades at some spawning grounds, whereas complete population replacement was evident at others. Observations of elevated differentiation in certain genomic regions are consistent with adaptive divergence between the groups, indicating that they may respond differently to environmental variation. Significantly increased temporal changes at a subset of loci also suggest that adaptation may be ongoing. These findings illustrate the power of spatiotemporal population genomics for revealing biocomplexity in both space and time and for informing future fisheries management and conservation efforts. PMID:23789034

  1. First feed affects the expressions of microRNA and their targets in Atlantic cod.

    PubMed

    Bizuayehu, Teshome Tilahun; Furmanek, Tomasz; Karlsen, Ørjan; van der Meeren, Terje; Edvardsen, Rolf Brudvik; Rønnestad, Ivar; Hamre, Kristin; Johansen, Steinar D; Babiak, Igor

    2016-04-14

    To our knowledge, there is no report on microRNA (miRNA) expression and their target analysis in relation to the type of the first feed and its effect on the further growth of fish. Atlantic cod (Gadus morhua) larvae have better growth and development performance when fed natural zooplankton as a start-feed, as compared with those fed typical aquaculture start-feeds. In our experiment, two groups of Atlantic cod larvae were fed reference feed (zooplankton, mostly copepods, filtered from a seawater pond) v. aquaculture feeds: enriched rotifers (Brachionus sp.) and later brine shrimp (Artemia salina). We examined the miRNA expressions of six defined developmental stages as determined and standardised by body length from first feeding for both diet groups. We found eight miRNA (miR-9, miR-19a, miR-130b, miR-146, miR-181a, miR-192, miR-206 and miR-11240) differentially expressed between the two feeding groups in at least one developmental stage. We verified the next-generation sequencing data using real-time RT-PCR. We found 397 putative targets (mRNA) to the differentially expressed miRNA; eighteen of these mRNA showed differential expression in at least one stage. The patterns of differentially expressed miRNA and their putative target mRNA were mostly inverse, but sometimes also concurrent. The predicted miRNA targets were involved in different pathways, including metabolic, phototransduction and signalling pathways. The results of this study provide new nutrigenomic information on the potential role of miRNA in mediating nutritional effects on growth during the start-feeding period in fish larvae.

  2. Trans-species polymorphism at antimicrobial innate immunity cathelicidin genes of Atlantic cod and related species

    PubMed Central

    Árnason, Einar

    2015-01-01

    Natural selection, the most important force in evolution, comes in three forms. Negative purifying selection removes deleterious variation and maintains adaptations. Positive directional selection fixes beneficial variants, producing new adaptations. Balancing selection maintains variation in a population. Important mechanisms of balancing selection include heterozygote advantage, frequency-dependent advantage of rarity, and local and fluctuating episodic selection. A rare pathogen gains an advantage because host defenses are predominantly effective against prevalent types. Similarly, a rare immune variant gives its host an advantage because the prevalent pathogens cannot escape the host’s apostatic defense. Due to the stochastic nature of evolution, neutral variation may accumulate on genealogical branches, but trans-species polymorphisms are rare under neutrality and are strong evidence for balancing selection. Balanced polymorphism maintains diversity at the major histocompatibility complex (MHC) in vertebrates. The Atlantic cod is missing genes for both MHC-II and CD4, vital parts of the adaptive immune system. Nevertheless, cod are healthy in their ecological niche, maintaining large populations that support major commercial fisheries. Innate immunity is of interest from an evolutionary perspective, particularly in taxa lacking adaptive immunity. Here, we analyze extensive amino acid and nucleotide polymorphisms of the cathelicidin gene family in Atlantic cod and closely related taxa. There are three major clusters, Cath1, Cath2, and Cath3, that we consider to be paralogous genes. There is extensive nucleotide and amino acid allelic variation between and within clusters. The major feature of the results is that the variation clusters by alleles and not by species in phylogenetic trees and discriminant analysis of principal components. Variation within the three groups shows trans-species polymorphism that is older than speciation and that is suggestive of

  3. "Islands of Divergence" in the Atlantic Cod Genome Represent Polymorphic Chromosomal Rearrangements.

    PubMed

    Sodeland, Marte; Jorde, Per Erik; Lien, Sigbjørn; Jentoft, Sissel; Berg, Paul R; Grove, Harald; Kent, Matthew P; Arnyasi, Mariann; Olsen, Esben Moland; Knutsen, Halvor

    2016-04-11

    In several species genetic differentiation across environmental gradients or between geographically separate populations has been reported to center at "genomic islands of divergence," resulting in heterogeneous differentiation patterns across genomes. Here, genomic regions of elevated divergence were observed on three chromosomes of the highly mobile fish Atlantic cod (Gadus morhua) within geographically fine-scaled coastal areas. The "genomic islands" extended at least 5, 9.5, and 13 megabases on linkage groups 2, 7, and 12, respectively, and coincided with large blocks of linkage disequilibrium. For each of these three chromosomes, pairs of segregating, highly divergent alleles were identified, with little or no gene exchange between them. These patterns of recombination and divergence mirror genomic signatures previously described for large polymorphic inversions, which have been shown to repress recombination across extensive chromosomal segments. The lack of genetic exchange permits divergence between noninverted and inverted chromosomes in spite of gene flow. For the rearrangements on linkage groups 2 and 12, allelic frequency shifts between coastal and oceanic environments suggest a role in ecological adaptation, in agreement with recently reported associations between molecular variation within these genomic regions and temperature, oxygen, and salinity levels. Elevated genetic differentiation in these genomic regions has previously been described on both sides of the Atlantic Ocean, and we therefore suggest that these polymorphisms are involved in adaptive divergence across the species distributional range. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  4. “Islands of Divergence” in the Atlantic Cod Genome Represent Polymorphic Chromosomal Rearrangements

    PubMed Central

    Sodeland, Marte; Jorde, Per Erik; Lien, Sigbjørn; Jentoft, Sissel; Berg, Paul R.; Grove, Harald; Kent, Matthew P.; Arnyasi, Mariann; Olsen, Esben Moland; Knutsen, Halvor

    2016-01-01

    In several species genetic differentiation across environmental gradients or between geographically separate populations has been reported to center at “genomic islands of divergence,” resulting in heterogeneous differentiation patterns across genomes. Here, genomic regions of elevated divergence were observed on three chromosomes of the highly mobile fish Atlantic cod (Gadus morhua) within geographically fine-scaled coastal areas. The “genomic islands” extended at least 5, 9.5, and 13 megabases on linkage groups 2, 7, and 12, respectively, and coincided with large blocks of linkage disequilibrium. For each of these three chromosomes, pairs of segregating, highly divergent alleles were identified, with little or no gene exchange between them. These patterns of recombination and divergence mirror genomic signatures previously described for large polymorphic inversions, which have been shown to repress recombination across extensive chromosomal segments. The lack of genetic exchange permits divergence between noninverted and inverted chromosomes in spite of gene flow. For the rearrangements on linkage groups 2 and 12, allelic frequency shifts between coastal and oceanic environments suggest a role in ecological adaptation, in agreement with recently reported associations between molecular variation within these genomic regions and temperature, oxygen, and salinity levels. Elevated genetic differentiation in these genomic regions has previously been described on both sides of the Atlantic Ocean, and we therefore suggest that these polymorphisms are involved in adaptive divergence across the species distributional range. PMID:26983822

  5. Multiple specialised goose-type lysozymes potentially compensate for an exceptional lack of chicken-type lysozymes in Atlantic cod.

    PubMed

    Seppola, Marit; Bakkemo, Kathrine Ryvold; Mikkelsen, Helene; Myrnes, Bjørnar; Helland, Ronny; Irwin, David M; Nilsen, Inge W

    2016-06-21

    Previous analyses of the Atlantic cod genome showed unique combinations of lacking and expanded number of genes for the immune system. The present study examined lysozyme activity, lysozyme gene distribution and expression in cod. Enzymatic assays employing specific bacterial lysozyme inhibitors provided evidence for presence of g-type, but unexpectedly not for c-type lysozyme activity. Database homology searches failed to identify any c-type lysozyme gene in the cod genome or in expressed sequence tags from cod. In contrast, we identified four g-type lysozyme genes (LygF1a-d) constitutively expressed, although differentially, in all cod organs examined. The active site glutamate residue is replaced by alanine in LygF1a, thus making it enzymatic inactive, while LygF1d was found in two active site variants carrying alanine or glutamate, respectively. In vitro and in vivo infection by the intracellular bacterium Francisella noatunensis gave a significantly reduced LygF1a and b expression but increased expression of the LygF1c and d genes as did also the interferon gamma (IFNγ) cytokine. These results demonstrate a lack of c-type lysozyme that is unprecedented among vertebrates. Our results further indicate that serial gene duplications have produced multiple differentially regulated cod g-type lysozymes with specialised functions potentially compensating for the lack of c-type lysozymes.

  6. Multiple specialised goose-type lysozymes potentially compensate for an exceptional lack of chicken-type lysozymes in Atlantic cod

    PubMed Central

    Seppola, Marit; Bakkemo, Kathrine Ryvold; Mikkelsen, Helene; Myrnes, Bjørnar; Helland, Ronny; Irwin, David M.; Nilsen, Inge W.

    2016-01-01

    Previous analyses of the Atlantic cod genome showed unique combinations of lacking and expanded number of genes for the immune system. The present study examined lysozyme activity, lysozyme gene distribution and expression in cod. Enzymatic assays employing specific bacterial lysozyme inhibitors provided evidence for presence of g-type, but unexpectedly not for c-type lysozyme activity. Database homology searches failed to identify any c-type lysozyme gene in the cod genome or in expressed sequence tags from cod. In contrast, we identified four g-type lysozyme genes (LygF1a-d) constitutively expressed, although differentially, in all cod organs examined. The active site glutamate residue is replaced by alanine in LygF1a, thus making it enzymatic inactive, while LygF1d was found in two active site variants carrying alanine or glutamate, respectively. In vitro and in vivo infection by the intracellular bacterium Francisella noatunensis gave a significantly reduced LygF1a and b expression but increased expression of the LygF1c and d genes as did also the interferon gamma (IFNγ) cytokine. These results demonstrate a lack of c-type lysozyme that is unprecedented among vertebrates. Our results further indicate that serial gene duplications have produced multiple differentially regulated cod g-type lysozymes with specialised functions potentially compensating for the lack of c-type lysozymes. PMID:27324690

  7. Influence of environmental changes in the north-western Atlantic Ocean on a parasite, Echinorhynchus gadi (Acanthocephala) of Atlantic cod ( Gadus morhua) occurring off coastal Labrador, Canada.

    PubMed

    Khan, R A

    2008-09-01

    A study was conducted to determine the influence of environmental change on an endoparasite, Echinorhynchus gadi (Acanthocephala) of Atlantic cod (Gadus morhua) over a 30-year period off the coast of Labrador in the north-western Atlantic, North Atlantic Fisheries Organization subareas 2J-3K. Cod, once an abundant fish species that had been commercially exploited for many decades, declined precipitously during the mid-1980s onwards. This decline was attributed to climatic changes that affected the entire food chain from zooplankton to fish, sea birds and marine mammals. A monitoring programme was introduced, sampling cod by otter trawling using research vessels. The fish, after capture, were frozen at - 20 degrees C, subsequently thawed and the digestive tract removed and examined for the parasite in 2006. Data from samples taken in 1976, 1980-81, 1986, 1990, 2000 and 2003 were compared statistically with those collected in 2006. The results indicate a decline in the prevalence and mean abundance of E. gadi in 1986 with a minimum in 2000 but increasing gradually in 2003 and 2006. These changes were coincident initially with a decline of oceanic temperature and the entire food web, including capelin (Mallotus villosus), a preferred prey of cod and primary source of E. gadi. The increase in prevalence and mean abundance of the parasite in 2006 were associated with an increase of oceanic temperature and the return of small schools of capelin to offshore areas. Cod older than 4 years harboured a greater abundance of E. gadi than younger fish, while no difference was observed between the sexes. The results suggest that the abundance of E. gadi can be useful as a bioindicator of environmental changes in the north-western Atlantic.

  8. Molecular ontogenesis of digestive capability and associated endocrine control in Atlantic cod (Gadus morhua) larvae.

    PubMed

    Kortner, Trond M; Overrein, Ingrid; Oie, Gunvor; Kjørsvik, Elin; Bardal, Tora; Wold, Per-Arvid; Arukwe, Augustine

    2011-10-01

    We have profiled the expression of twelve genes, in order to provide an overview on the molecular ontogeny of digestive capability with the associated endocrine control during Atlantic cod (Gadus morhua) larval development. Enzyme activity levels for the key digestive enzyme, trypsin, was also measured. Specifically, transcripts for trypsin, amylase, lipolytic enzymes: bile salt activated lipase (BAL), phospholipase A2 (PLA2) and Acyl CoA dehydrogenase (ACADM), regulatory peptides: neuropeptide Y (NPY), orexin (OX) cholecystokinin (CCK) and cocaine and amphetamine-related transcript (CART), the somatotropic factors: growth hormone (GH), preprosomatostatin 1 (PPSS1) and thyroid hormone receptors (TRα and TRβ) were analyzed using quatitative (real-time) polymerase chain reaction (qPCR). Trypsin and BAL mRNA levels peaked at approximately day 17 and 25 post-hatch, respectively, and thereafter displayed a decreasing pattern until metamorphosis. GH mRNA levels decreased moderately from 3 to 33dph, and thereafter, an increase was observed until 46dph. TRα mRNA levels showed a fluctuating pattern peaking at day 39 post-hatch. TRβ mRNA levels were too low to obtain quantitative measurements. Amylase mRNA slightly increased from day 3 to 17 post-hatch, and thereafter showed a steady decrease until day 60. Interestingly, PLA2 mRNA expression showed a consistent increase throughout the study period, indicating an increasingly important role during larval development. Overall, data from this study indicate that cod larvae show differential developmental mode of expression patterns for key genes and endocrine factors that regulate digestive capability, growth and development. These data are discussed in relation to larval trypsin enzyme activity and previous reports for other teleost species. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Rested and stressed farmed Atlantic cod (Gadus morhua) chilled in ice or slurry and effects on quality.

    PubMed

    Digre, Hanne; Erikson, Ulf; Aursand, Ida G; Gallart-Jornet, Lorena; Misimi, Ekrem; Rustad, Turid

    2011-01-01

    The main objectives of this study were to investigate (1) whether rested harvest of farmed cod was better maintained by chilling with slurry rather than by traditional ice storage, (2) whether chilling with slurry would be a feasible chilling method to assure low core temperatures (≤0 °C) at packing of gutted fish, and (3) the effects of superchilling compared with traditional ice on selected quality parameters of cod during storage. In the experiment, seawater slurry at -2.0 ± 0.3 °C was used. Anesthetized (AQUI-S™), percussion stunned, and stressed cod chilled in slurry were compared. Cod stored on ice were used as reference group. The fish were evaluated at the day of slaughter, and after 7 and 14 d of storage according to handling stress (initial muscle pH, muscle twitches, rigor mortis), core temperatures, quality index method, microbial counts, weight changes, salt and water content, water distribution, pH, adenosine triphosphate-degradation products, K-value, water-holding capacity, fillet color, and texture. Chilling cod in slurry was more rapid than chilling in ice. Prechilling (1 d) of cod in slurry before subsequent ice storage resulted in lower quality 7 d postmortem compared with both ice and continuous slurry storage. The potential advantages of superchilling became more prominent after 14 d with lower microbiological activity, better maintenance of freshness (lower total quality index scores and lower K-values) compared with fish stored on ice. A drawback with slurry-stored fish was that cloudy eyes developed earlier, in addition to weight gain and salt uptake compared to ice-stored fish. Practical Application: Chilling is an essential operation in any fish-processing plant. This manuscript addresses different applications of slurry ice in the processing and storage of Atlantic cod. Cod quality was assessed after 7 and 14 d of iced and superchilled storage.

  10. Effects of ocean acidification increase embryonic sensitivity to thermal extremes in Atlantic cod, Gadus morhua.

    PubMed

    Dahlke, Flemming T; Leo, Elettra; Mark, Felix C; Pörtner, Hans-Otto; Bickmeyer, Ulf; Frickenhaus, Stephan; Storch, Daniela

    2017-04-01

    Thermal tolerance windows serve as a powerful tool for estimating the vulnerability of marine species and their life stages to increasing temperature means and extremes. However, it remains uncertain to which extent additional drivers, such as ocean acidification, modify organismal responses to temperature. This study investigated the effects of CO2 -driven ocean acidification on embryonic thermal sensitivity and performance in Atlantic cod, Gadus morhua, from the Kattegat. Fertilized eggs were exposed to factorial combinations of two PCO2 conditions (400 μatm vs. 1100 μatm) and five temperature treatments (0, 3, 6, 9 and 12 °C), which allow identifying both lower and upper thermal tolerance thresholds. We quantified hatching success, oxygen consumption (MO2 ) and mitochondrial functioning of embryos as well as larval morphometrics at hatch and the abundance of acid-base-relevant ionocytes on the yolk sac epithelium of newly hatched larvae. Hatching success was high under ambient spawning conditions (3-6 °C), but decreased towards both cold and warm temperature extremes. Elevated PCO2 caused a significant decrease in hatching success, particularly at cold (3 and 0 °C) and warm (12 °C) temperatures. Warming imposed limitations to MO2 and mitochondrial capacities. Elevated PCO2 stimulated MO2 at cold and intermediate temperatures, but exacerbated warming-induced constraints on MO2 , indicating a synergistic interaction with temperature. Mitochondrial functioning was not affected by PCO2 . Increased MO2 in response to elevated PCO2 was paralleled by reduced larval size at hatch. Finally, ionocyte abundance decreased with increasing temperature, but did not differ between PCO2 treatments. Our results demonstrate increased thermal sensitivity of cod embryos under future PCO2 conditions and suggest that acclimation to elevated PCO2 requires reallocation of limited resources at the expense of embryonic growth. We conclude that ocean acidification constrains

  11. Direct and social genetic parameters for growth and fin damage traits in Atlantic cod (Gadus morhua)

    PubMed Central

    2014-01-01

    Background The aim of the study was to estimate genetic parameters for direct and social genetic effects (SGE) for growth and welfare traits in farmed Atlantic cod (Gadus morhua). A SGE refers to the effect of an individual’s genes on trait performance of its social partners. In total, 2100 individually tagged juveniles from 100 families at an average age of 222 days post-hatching were used. Each family was separated into three groups of seven fish, and were randomly assigned to 100 experimental tanks, together with fish from two other families. Body weight and length of the first, second and third dorsal fin and the caudal fin measured by digital image analysis were measured at the start of the experiment, after two weeks, and after six weeks. Fin erosion was scored subjectively after six weeks. Variance components estimated using a conventional animal model were compared to those of an animal model including a SGE. Results Heritabilities from the conventional animal model ranged from 0.24 to 0.34 for body weight and 0.05 to 0.80 for fin length. Heritabilities for fin erosion were highest for the first dorsal fin (0.83 ± 0.08, mean ± standard error) and lowest for the third dorsal fin (0.01 ± 0.04). No significant SGE were found for body weight, whereas SGE for fin lengths were significant after two and six weeks. Contributions to the total heritable variance were equal to 21.5% (6.1 ± 2.1) for the direct effect, 33.1% (9.4 ± 3.2) for the direct-social covariance, and 45.4% (12.9 ± 4.1) for the social variance for length of the first dorsal fin. For fin erosion, SGE were only significant for the second and third dorsal fin. Conclusions Including SGE for fin length and fin erosion in the animal model increased the estimated heritable variation. However, estimates of total heritable variances were inaccurate and a larger experiment is needed to accurately quantify total heritable variance. Despite this, our results demonstrate that

  12. Variation in embryonic mortality and maternal transcript expression among Atlantic cod (Gadus morhua) broodstock: a functional genomics study.

    PubMed

    Rise, Matthew L; Nash, Gordon W; Hall, Jennifer R; Booman, Marije; Hori, Tiago S; Trippel, Edward A; Gamperl, A Kurt

    2014-12-01

    Early life stage mortality is an important issue for Atlantic cod aquaculture, yet the impact of the cod maternal (egg) transcriptome on egg quality and mortality during embryonic development is poorly understood. In the present work, we studied embryonic mortality and maternal transcript expression using eggs from 15 females. Total mortality at 7days post-fertilization (7 dpf, segmentation stage) was used as an indice of egg quality. A 20,000 probe (20K) microarray experiment compared the 7hours post-fertilization (7 hpf, ~2-cell stage) egg transcriptome of the two lowest quality females (>90% mortality at 7 dpf) to that of the highest quality female (~16% mortality at 7 dpf). Forty-three microarray probes were consistently differentially expressed in both low versus high quality egg comparisons (25 higher expressed in low quality eggs, and 18 higher expressed in high quality eggs). The microarray experiment also identified many immune-relevant genes [e.g. interferon (IFN) pathway genes ifngr1 and ifrd1)] that were highly expressed in eggs of all 3 females regardless of quality. Twelve of the 43 candidate egg quality-associated genes, and ifngr1, ifrd1 and irf7, were included in a qPCR study with 7 hpf eggs from all 15 females. Then, the genes that were confirmed by qPCR to be greater than 2-fold differentially expressed between 7 hpf eggs from the lowest and highest quality females (dcbld1, ddc, and acy3 more highly expressed in the 2 lowest quality females; kpna7 and hacd1 more highly expressed in the highest quality female), and the 3 IFN pathway genes, were included in a second qPCR study with unfertilized eggs. While some maternal transcripts included in these qPCR studies were associated with extremes in egg quality, there was little correlation between egg quality and gene expression when all females were considered. Both dcbld1 and ddc showed greater than 100-fold differences in transcript expression between females and were potentially influenced by

  13. Detection of Francisella piscicida in Atlantic cod (Gadus morhua L) by the loop-mediated isothermal amplification (LAMP) reaction.

    PubMed

    Caipang, Christopher M A; Kulkarni, Amod; Brinchmann, Monica F; Korsnes, Kjetil; Kiron, Viswanath

    2010-06-01

    The loop-mediated isothermal amplification (LAMP) reaction was evaluated for its speed and sensitivity in detecting the presence of Francisella piscicida, the causative agent of francisellosis in Atlantic cod (Gadus morhua). Four primer sets, consisting of two outer and two inner, were designed from the groEL gene of the pathogen. The LAMP reaction was optimised at 63 degrees C for 1h using bacterial genomic DNA as the template and the products were visualised under ultra-violet light and analysed by agarose gel electrophoresis. A ladder-like pattern of bands, specific for F. piscicida, was amplified from positive samples. The method was highly specific for the detection of F. piscicida and was 100 times more sensitive than conventional PCR. In addition, the LAMP assay was able to detect the pathogen in kidney and splenic samples of naturally-infected Atlantic cod.

  14. Thermal stress alters expression of genes involved in one carbon and DNA methylation pathways in Atlantic cod embryos.

    PubMed

    Skjærven, Kaja H; Hamre, Kristin; Penglase, Samuel; Finn, Roderick Nigel; Olsvik, Pål A

    2014-03-16

    One-carbon (1-C) metabolism is essential for normal embryonic development through its regulation of DNA methylation and cell proliferation. With consideration to the potential future anthropogenic oceanic warming, we studied the effects of both acute thermal stress and continuous thermal stress (10°C) during Atlantic cod embryo development on the expression levels of genes associated with the 1-C metabolism, including DNA methyltransferases. We conducted a phylogenetic analysis of vertebrate DNA methyltransferases to determine the number and similarity of DNMT found in Atlantic cod. This analysis revealed that Atlantic cod have one maintenance dnmt (dnmt1) and five de novo DNMTs (dnmt4, dnmt3, dnmt3b, dnmt3aa, dnmt3ab). Stage specific changes in expression levels occurred for all genes analyzed. The effect of acute thermal stress was evaluated during early development. Compared to controls these experiments showed significant alterations in expression levels of several genes, that in some instances were reversed at later stages of development. A significant effect of continuous thermal stress was found in gastrula embryos where lower mRNA expression levels of 1-C metabolism, de novo DNMTs and cell proliferation genes were detected. One exception was the maintenance DNMT, which was only sensitive to acute and not continuous thermal stress. DNA methylation status indicated that blastula embryos were hypomethylated compared to spermatozoa and late gastrula stages. In post-gastrula stage, however, continuous thermal stress resulted in a higher degree of DNA methylation compared to controls. These data reveal that the regulation of epigenetically important transcripts in the 1-C metabolism of Atlantic cod embryos is sensitive to thermal stress. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Experimental Challenge of Atlantic Cod (Gadus morhua) with a Brucella pinnipedialis Strain from Hooded Seal (Cystophora cristata)

    PubMed Central

    Nymo, Ingebjørg Helena; Seppola, Marit; Al Dahouk, Sascha; Bakkemo, Kathrine Ryvold; Jiménez de Bagüés, María Pilar; Godfroid, Jacques; Larsen, Anett Kristin

    2016-01-01

    Pathology has not been observed in true seals infected with Brucella pinnipedialis. A lack of intracellular survival and multiplication of B. pinnipedialis in hooded seal (Cystophora cristata) macrophages in vitro indicates a lack of chronic infection in hooded seals. Both epidemiology and bacteriological patterns in the hooded seal point to a transient infection of environmental origin, possibly through the food chain. To analyse the potential role of fish in the transmission of B. pinnipedialis, Atlantic cod (Gadus morhua) were injected intraperitoneally with 7.5 x 107 bacteria of a hooded seal field isolate. Samples of blood, liver, spleen, muscle, heart, head kidney, female gonads and feces were collected on days 1, 7, 14 and 28 post infection to assess the bacterial load, and to determine the expression of immune genes and the specific antibody response. Challenged fish showed an extended period of bacteremia through day 14 and viable bacteria were observed in all organs sampled, except muscle, until day 28. Neither gross lesions nor mortality were recorded. Anti-Brucella antibodies were detected from day 14 onwards and the expression of hepcidin, cathelicidin, interleukin (IL)-1β, IL-10, and interferon (IFN)-γ genes were significantly increased in spleen at day 1 and 28. Primary mononuclear cells isolated from head kidneys of Atlantic cod were exposed to B. pinnipedialis reference (NCTC 12890) and hooded seal (17a-1) strain. Both bacterial strains invaded mononuclear cells and survived intracellularly without any major reduction in bacterial counts for at least 48 hours. Our study shows that the B. pinnipedialis strain isolated from hooded seal survives in Atlantic cod, and suggests that Atlantic cod could play a role in the transmission of B. pinnipedialis to hooded seals in the wild. PMID:27415626

  16. Experimental Challenge of Atlantic Cod (Gadus morhua) with a Brucella pinnipedialis Strain from Hooded Seal (Cystophora cristata).

    PubMed

    Nymo, Ingebjørg Helena; Seppola, Marit; Al Dahouk, Sascha; Bakkemo, Kathrine Ryvold; Jiménez de Bagüés, María Pilar; Godfroid, Jacques; Larsen, Anett Kristin

    2016-01-01

    Pathology has not been observed in true seals infected with Brucella pinnipedialis. A lack of intracellular survival and multiplication of B. pinnipedialis in hooded seal (Cystophora cristata) macrophages in vitro indicates a lack of chronic infection in hooded seals. Both epidemiology and bacteriological patterns in the hooded seal point to a transient infection of environmental origin, possibly through the food chain. To analyse the potential role of fish in the transmission of B. pinnipedialis, Atlantic cod (Gadus morhua) were injected intraperitoneally with 7.5 x 107 bacteria of a hooded seal field isolate. Samples of blood, liver, spleen, muscle, heart, head kidney, female gonads and feces were collected on days 1, 7, 14 and 28 post infection to assess the bacterial load, and to determine the expression of immune genes and the specific antibody response. Challenged fish showed an extended period of bacteremia through day 14 and viable bacteria were observed in all organs sampled, except muscle, until day 28. Neither gross lesions nor mortality were recorded. Anti-Brucella antibodies were detected from day 14 onwards and the expression of hepcidin, cathelicidin, interleukin (IL)-1β, IL-10, and interferon (IFN)-γ genes were significantly increased in spleen at day 1 and 28. Primary mononuclear cells isolated from head kidneys of Atlantic cod were exposed to B. pinnipedialis reference (NCTC 12890) and hooded seal (17a-1) strain. Both bacterial strains invaded mononuclear cells and survived intracellularly without any major reduction in bacterial counts for at least 48 hours. Our study shows that the B. pinnipedialis strain isolated from hooded seal survives in Atlantic cod, and suggests that Atlantic cod could play a role in the transmission of B. pinnipedialis to hooded seals in the wild.

  17. Cloning and characterization of neuropeptide Y (NPY) and cocaine and amphetamine regulated transcript (CART) in Atlantic cod (Gadus morhua).

    PubMed

    Kehoe, Amy S; Volkoff, Hélène

    2007-03-01

    Neuropeptide Y (NPY) and cocaine and amphetamine regulated transcript (CART) are two neuropeptides involved in the regulation of feeding in both mammals and fish. NPY stimulates feeding whereas CART inhibits feeding. In this study, we have cloned the full-length cDNA and complete genomic DNA sequences for NPY and CART in Atlantic cod. Atlantic cod preproNPY share a 45-85% identity with preproNPY from other fish whereas preproCART shows a 70% identity to CART peptides from zebrafish and goldfish. RT-PCR revealed that NPY mRNA is expressed in brain, in particular the forebrain, and in peripheral tissues, including intestine and kidney. CART mRNA is expressed throughout the brain and in ovaries. In order to assess the role of these peptides in the regulation of feeding, we examined changes in mRNA expression in the forebrain before, during and after a meal. NPY and CART mRNA both undergo peri-prandial changes in expression, with NPY levels being elevated around meal time and CART showing a decline 2 h after a meal. Food deprivation for 7 days induced a decrease in CART mRNA expression in the brain but did not affect NPY mRNA expression. Overall, our results suggest that NPY and CART are conserved peptides that might be involved in the regulation of feeding and other physiological functions in Atlantic cod.

  18. Integrative Approach for the Reliable Detection and Specific Identification of the Microsporidium Loma morhua in Atlantic Cod (Gadus morhua).

    PubMed

    Frenette, Aaron P; Eydal, Matthías; Hansen, Haakon; Burt, Michael D B; Duffy, Michael S

    2017-01-01

    Microsporidia are fungal parasites that infect diverse invertebrate and vertebrate hosts. Finfish aquaculture supports epizootics due to high host density and the high biotic potential of these parasites. Reliable methods for parasite detection and identification are a necessary precursor to empirical assessment of strategies to mitigate the effects of these pathogens during aquaculture. We developed an integrative approach to detect and identify Loma morhua infecting Atlantic cod. We show that the spleen is more reliable than the commonly presumed gills as best organ for parasite detection in spite of substantial morphological plasticity in xenoma complexes. We developed rDNA primers with 100% sensitivity in detecting L. morhua and with utility in distinguishing some congeneric Loma species. ITS sequencing is necessary to distinguish L. morhua from other congeneric microsporidia due to intraspecific nucleotide variation. 64% of L. morhua ITS variants from Atlantic cod have a 9-nucleotide motif that distinguishes it from Loma spp. infecting non-Gadus hosts. The remaining 36% of ITS variants from Atlantic cod are distinguished from currently represented Loma spp., particularly those infecting Gadus hosts, based on a 14-nucleotide motif. This research approach is amenable to developing templates in support of reliable detection and identification of other microsporidian parasites in fishes.

  19. Unraveling the evolution of the Atlantic cod's (Gadus morhua L.) alternative immune strategy.

    PubMed

    Malmstrøm, Martin; Jentoft, Sissel; Gregers, Tone F; Jakobsen, Kjetill S

    2013-01-01

    Genes encoding the major histocompatibility complex (MHC) have been thought to play a vital role in the adaptive immune system in all vertebrates. The discovery that Atlantic cod (Gadus morhua) has lost important components of the MHC II pathway, accompanied by an unusually high number of MHC I genes, shed new light on the evolution and plasticity of the immune system of teleosts as well as in higher vertebrates. The overall aim of this study was to further investigate the highly expanded repertoire of MHC I genes using a cDNA approach to obtain sequence information of both the binding domains and the sorting signaling potential in the cytoplasmic tail. Here we report a novel combination of two endosomal sorting motifs, one tyrosine-based associated with exogenous peptide presentation by cross-presenting MHCI molecules, and one dileucine-based associated with normal MHC II functionality. The two signal motifs were identified in the cytoplasmic tail in a subset of the genes. This indicates that these genes have evolved MHC II-like functionality, allowing a more versatile use of MHC I through cross-presentation. Such an alternative immune strategy may have arisen through adaptive radiation and acquisition of new gene function as a response to changes in the habitat of its ancestral lineage.

  20. Severe tissue damage in Atlantic cod larvae under increasing ocean acidification

    NASA Astrophysics Data System (ADS)

    Frommel, Andrea Y.; Maneja, Rommel; Lowe, David; Malzahn, Arne M.; Geffen, Audrey J.; Folkvord, Arild; Piatkowski, Uwe; Reusch, Thorsten B. H.; Clemmesen, Catriona

    2012-01-01

    Ocean acidification, caused by increasing atmospheric concentrations of CO2 (refs , , ), is one of the most critical anthropogenicthreats to marine life. Changes in seawater carbonate chemistry have the potential to disturb calcification, acid-base regulation, blood circulation and respiration, as well as the nervous system of marine organisms, leading to long-term effects such as reduced growth rates and reproduction. In teleost fishes, early life-history stages are particularly vulnerable as they lack specialized internal pH regulatory mechanisms. So far, impacts of relevant CO2 concentrations on larval fish have been found in behaviour and otolith size, mainly in tropical, non-commercial species. Here we show detrimental effects of ocean acidification on the development of a mass-spawning fish species of high commercial importance. We reared Atlantic cod larvae at three levels of CO2, (1) present day, (2) end of next century and (3) an extreme, coastal upwelling scenario, in a long-term ( months) mesocosm experiment. Exposure to CO2 resulted in severe to lethal tissue damage in many internal organs, with the degree of damage increasing with CO2 concentration. As larval survival is the bottleneck to recruitment, ocean acidification has the potential to act as an additional source of natural mortality, affecting populations of already exploited fish stocks.

  1. Maternal transfer and transcriptional onset of immune genes during ontogenesis in Atlantic cod.

    PubMed

    Seppola, Marit; Johnsen, Hanne; Mennen, Saskia; Myrnes, Bjørnar; Tveiten, Helge

    2009-11-01

    The immune system in teleosts is not completely developed during embryonic and larval stages and immune competence is assumed to be restricted. This study is the first to address whether immune transcripts are maternally transferred to offspring and when immune genes are transcriptionally active in Atlantic cod (Gadus morhua). In unfertilised eggs, transcripts encoding lysozyme and cathelicidin were found indicating maternal transfer of antibacterial transcripts. Lysozyme activity was also present at this stage suggesting the presence of a functional protein. Transcripts of two other putative antibacterial genes (hepcidin and pentraxin) and antiviral genes (ISG15 and LGP2) were absent in unfertilised eggs. The transcriptional onset of these genes occurred during the gastrula period. Transcripts of the heavy chain constant regions of the immunoglobulin (Ig) D, membrane-associated and secreted form of IgM were absent in unfertilised eggs. Transcription of the heavy chain locus commenced at low levels during the segmentation period indicating the onset of B-cell development. Most innate immune genes showed an increase in transcription around hatch and first feeding, indicating a preparation for increased pathogen exposure at this time. Prior to and during metamorphosis all genes showed a pronounced elevation in transcript levels indicating a further maturation of the immune system during this period.

  2. Diversification of the expanded teleost-specific toll-like receptor family in Atlantic cod, Gadus morhua

    PubMed Central

    2012-01-01

    Background Toll-like receptors (Tlrs) are major molecular pattern recognition receptors of the innate immune system. Atlantic cod (Gadus morhua) is the first vertebrate known to have lost most of the mammalian Tlr orthologues, particularly all bacterial recognising and other cell surface Tlrs. On the other hand, its genome encodes a unique repertoire of teleost-specific Tlrs. The aim of this study was to investigate if these duplicate Tlrs have been retained through adaptive evolution to compensate for the lack of other cell surface Tlrs in the cod genome. Results In this study, one tlr21, 12 tlr22 and two tlr23 genes representing the teleost-specific Tlr family have been cloned and characterised in cod. Phylogenetic analysis grouped all tlr22 genes under a single clade, indicating that the multiple cod paralogues have arisen through lineage-specific duplications. All tlrs examined were transcribed in immune-related tissues as well as in stomach, gut and gonads of adult cod and were differentially expressed during early development. These tlrs were also differentially regulated following immune challenge by immersion with Vibrio anguillarum, indicating their role in the immune response. An increase in water temperature from 4 to 12°C was associated with a 5.5-fold down-regulation of tlr22d transcript levels in spleen. Maximum likelihood analysis with different evolution models revealed that tlr22 genes are under positive selection. A total of 24 codons were found to be positively selected, of which 19 are in the ligand binding region of ectodomain. Conclusion Positive selection pressure coupled with experimental evidence of differential expression strongly support the hypothesis that teleost-specific tlr paralogues in cod are undergoing neofunctionalisation and can recognise bacterial pathogen-associated molecular patterns to compensate for the lack of other cell surface Tlrs. PMID:23273344

  3. The effect of temperature and body size on metabolic scope of activity in juvenile Atlantic cod Gadus morhua L.

    PubMed

    Tirsgaard, Bjørn; Behrens, Jane W; Steffensen, John F

    2015-01-01

    Changes in ambient temperature affect the physiology and metabolism and thus the distribution of fish. In this study we used intermittent flow respirometry to determine the effect of temperature (2, 5, 10, 15 and 20°C) and wet body mass (BM) (~30-460g) on standard metabolic rate (SMR, mgO2h(-1)), maximum metabolic rate (MMR, mgO2h(-1)) and metabolic scope (MS, mgO2h(-1)) of juvenile Atlantic cod. SMR increased with BM irrespectively of temperature, resulting in an average scaling exponent of 0.87 (0.82-0.92). Q10 values were 1.8-2.1 at temperatures between 5 and 15°C but higher (2.6-4.3) between 2 and 5°C and lower (1.6-1.4) between 15 and 20°C in 200 and 450g cod. MMR increased with temperature in the smallest cod (50g) but in the larger cod MMR plateaued between 10, 15 and 20°C. This resulted in a negative correlation between the optimal temperature for MS (Topt) and BM, Topt being respectively 14.5, 11.8 and 10.9°C in a 50, 200 and 450g cod. Irrespective of BM cold water temperatures resulted in a reduction (30-35%) of MS whereas the reduction of MS at warm temperatures was only evident for larger fish (200 and 450g), caused by plateauing of MMR at 10°C and above. Warm temperatures thus seem favourable for smaller (50g) juvenile cod, but not for larger conspecifics (200 and 450g). Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Temperature Modulates the Effects of Ocean Acidification on Intestinal Ion Transport in Atlantic Cod, Gadus morhua.

    PubMed

    Hu, Marian Y; Michael, Katharina; Kreiss, Cornelia M; Stumpp, Meike; Dupont, Sam; Tseng, Yung-Che; Lucassen, Magnus

    2016-01-01

    CO2-driven seawater acidification has been demonstrated to enhance intestinal bicarbonate secretion rates in teleosts, leading to an increased release of CaCO3 under simulated ocean acidification scenarios. In this study, we investigated if increasing CO2 levels stimulate the intestinal acid-base regulatory machinery of Atlantic cod (Gadus morhua) and whether temperatures at the upper limit of thermal tolerance stimulate or counteract ion regulatory capacities. Juvenile G. morhua were acclimated for 4 weeks to three CO2 levels (550, 1200, and 2200 μatm) covering present and near-future natural variability, at optimum (10°C) and summer maximum temperature (18°C), respectively. Immunohistochemical analyses revealed the subcellular localization of ion transporters, including Na(+)/K(+)-ATPase (NKA), Na(+)/H(+)-exchanger 3 (NHE3), Na(+)/[Formula: see text] cotransporter (NBC1), pendrin-like Cl(-)/[Formula: see text] exchanger (SLC26a6), V-type H(+)-ATPase subunit a (VHA), and Cl(-) channel 3 (CLC3) in epithelial cells of the anterior intestine. At 10°C, proteins and mRNA were generally up-regulated for most transporters in the intestinal epithelium after acclimation to higher CO2 levels. This supports recent findings demonstrating increased intestinal [Formula: see text] secretion rates in response to CO2 induced seawater acidification. At 18°C, mRNA expression and protein concentrations of most ion transporters remained unchanged or were even decreased, suggesting thermal compensation. This response may be energetically favorable to retain blood [Formula: see text] levels to stabilize pHe, but may negatively affect intestinal salt and water resorption of marine teleosts in future oceans.

  5. Nucleotide enrichment of live feed: a promising protocol for rearing of Atlantic cod Gadus morhua larvae.

    PubMed

    Lanes, Carlos Frederico Ceccon; Bolla, Sylvie; Fernandes, Jorge M O; Nicolaisen, Ove; Kiron, Viswanath; Babiak, Igor

    2012-10-01

    We investigated the effect of two commercial nucleotide products (NT1 and NT2), administered through live feed, on growth and stress tolerance of Atlantic cod larvae. Expression of genes related to muscle growth (igf-1, igf1r, igf-2, fst, fgf6, myod, and myhc) and nucleotide metabolism (uox, hprt, ndk, and uck) was evaluated during larval development. In addition, the expression of genes related to stress (hif-1α, hif-2α, hif-3α, and mb) was studied after an air exposure stress test. The enrichment of rotifers with nucleotides did not reveal any difference in nucleotide profiles, the exception being the RNA level of the NT1-enriched group that was significantly higher than the unenriched rotifer. Unenriched Artemia showed poor nucleotide profiles compared to enriched Artemia since 5' UMP, 5' GMP, and 5' AMP were observed only in the nucleotide groups. At 38 days post-hatch (dph), NT1 group had significantly higher dry weight (3.1 ± 0.1 mg) than the control (CON; 2.3 ± 0.1 mg). The treatments did not produce any significant differences in the expression of the key myogenic genes. Among the genes associated with nucleotide metabolism, ndk was down-regulated in NT1 at 38 dph. In the air exposure test, survival was significantly higher in the CON (77 ± 6 %) than in NT1 (48 ± 3 %) and NT2 (50 ± 3 %). After air exposure, mb was expressed at lower levels in NT2 group, hif-2α was induced in NT1 group, and hif-3α was upregulated in all groups. Our findings indicate that the improvement in the nucleotide profile of Artemia upon nucleotide enrichment could eventuate in the rapid growth of larvae.

  6. Homing and group cohesion in Atlantic cod Gadus morhua revealed by tagging experiments.

    PubMed

    Tamdrari, H; Brêthes, J-C; Castonguay, M; Duplisea, D E

    2012-07-01

    Homing behaviour and group cohesion in Atlantic cod Gadus morhua from the northern Gulf of St Lawrence were studied based on tagging-recapture data from two periods, the 1980s and a recent period from 1996 to 2008. Two or more tags from a single tagging experiment were frequently recovered together in subsequent years. The null hypothesis was tested that the frequency of matching tag recoveries occurred by chance only through random mixing of tagged G. morhua before their recapture by the commercial fishery. The alternative hypothesis was that non-random, positive association (group cohesion) existed among tagged individuals that persisted through time and during migrations. Results show that the G. morhua population exhibits a homing behaviour, with temporal stability across seasons and years: 50% of recaptured fish in the recent period were caught <34 km from their mark site, even 3 years after release. In the 1980s, G. morhua were located at <10 km from their release site 1 year after tagging during summer and at <16 km during spring and autumn combined. Despite the increasing distance between the mark and recapture sites over time, the difference was not significant. In addition, occurrences of two or more tagged fish from the same release event that were caught together indicated a non-random association among individual fish for periods of one to several years and through migrations over several hundred kilometres. Hence G. morhua showed group cohesion in addition to site fidelity. These two interacting behaviours may be fundamental for the rebuilding and conservation of depleted fish stocks. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  7. Temperature Modulates the Effects of Ocean Acidification on Intestinal Ion Transport in Atlantic Cod, Gadus morhua

    PubMed Central

    Hu, Marian Y.; Michael, Katharina; Kreiss, Cornelia M.; Stumpp, Meike; Dupont, Sam; Tseng, Yung-Che; Lucassen, Magnus

    2016-01-01

    CO2-driven seawater acidification has been demonstrated to enhance intestinal bicarbonate secretion rates in teleosts, leading to an increased release of CaCO3 under simulated ocean acidification scenarios. In this study, we investigated if increasing CO2 levels stimulate the intestinal acid–base regulatory machinery of Atlantic cod (Gadus morhua) and whether temperatures at the upper limit of thermal tolerance stimulate or counteract ion regulatory capacities. Juvenile G. morhua were acclimated for 4 weeks to three CO2 levels (550, 1200, and 2200 μatm) covering present and near-future natural variability, at optimum (10°C) and summer maximum temperature (18°C), respectively. Immunohistochemical analyses revealed the subcellular localization of ion transporters, including Na+/K+-ATPase (NKA), Na+/H+-exchanger 3 (NHE3), Na+/HCO3− cotransporter (NBC1), pendrin-like Cl−/HCO3− exchanger (SLC26a6), V-type H+-ATPase subunit a (VHA), and Cl− channel 3 (CLC3) in epithelial cells of the anterior intestine. At 10°C, proteins and mRNA were generally up-regulated for most transporters in the intestinal epithelium after acclimation to higher CO2 levels. This supports recent findings demonstrating increased intestinal HCO3− secretion rates in response to CO2 induced seawater acidification. At 18°C, mRNA expression and protein concentrations of most ion transporters remained unchanged or were even decreased, suggesting thermal compensation. This response may be energetically favorable to retain blood HCO3− levels to stabilize pHe, but may negatively affect intestinal salt and water resorption of marine teleosts in future oceans. PMID:27313538

  8. Global transcriptome analysis identifies regulated transcripts and pathways activated during oogenesis and early embryogenesis in Atlantic cod.

    PubMed

    Kleppe, Lene; Edvardsen, Rolf Brudvik; Furmanek, Tomasz; Taranger, Geir Lasse; Wargelius, Anna

    2014-07-01

    The molecular mechanisms underlying oogenesis and maternally controlled embryogenesis in fish are not fully understood, especially in marine species. Our aim was to study the egg and embryo transcriptome during oogenesis and early embryogenesis in Atlantic cod. Follicles from oogenesis stages (pre-, early-, and late-vitellogenic), ovulated eggs, and two embryonic stages (blastula, gastrula) were collected from broodstock fish and fertilized eggs. Gene expression profiles were measured in a 44 K oligo microarray consisting of 23,000 cod genes. Hundreds of differentially expressed genes (DEGs) were identified in the follicle stages investigated, implicating a continuous accumulation and degradation of polyadenylated transcripts throughout oogenesis. Very few DEGs were identified from ovulated egg to blastula, showing a more stable maternal RNA pool in early embryonic stages. The highest induction of expression was observed between blastula and gastrula, signifying the onset of zygotic transcription. During early vitellogenesis, several of the most upregulated genes are linked to nervous system signaling, suggesting increasing requirements for ovarian synaptic signaling to stimulate the rapid growth of oocytes. Highly upregulated genes during late vitellogenesis are linked to protein processing, fat metabolism, osmoregulation, and arrested meiosis. One of the genes with the highest upregulation in the ovulated egg is involved in oxidative phosphorylation, reflecting increased energy requirements during fertilization and the first rapid cell divisions of early embryogenesis. In conclusion, this study provides a large-scale presentation of the Atlantic cod's maternally controlled transcriptome in ovarian follicles through oogenesis, ovulated eggs, and early embryos.

  9. Historical DNA reveals the demographic history of Atlantic cod (Gadus morhua) in medieval and early modern Iceland.

    PubMed

    Ólafsdóttir, Guðbjörg Ásta; Westfall, Kristen M; Edvardsson, Ragnar; Pálsson, Snæbjörn

    2014-02-22

    Atlantic cod (Gadus morhua) vertebrae from archaeological sites were used to study the history of the Icelandic Atlantic cod population in the time period of 1500-1990. Specifically, we used coalescence modelling to estimate population size and fluctuations from the sequence diversity at the cytochrome b (cytb) and Pantophysin I (PanI) loci. The models are consistent with an expanding population during the warm medieval period, large historical effective population size (NE), a marked bottleneck event at 1400-1500 and a decrease in NE in early modern times. The model results are corroborated by the reduction of haplotype and nucleotide variation over time and pairwise population distance as a significant portion of nucleotide variation partitioned across the 1550 time mark. The mean age of the historical fished stock is high in medieval times with a truncation in age in early modern times. The population size crash coincides with a period of known cooling in the North Atlantic, and we conclude that the collapse may be related to climate or climate-induced ecosystem change.

  10. Evolutionary history and adaptive significance of the polymorphic Pan I in migratory and stationary populations of Atlantic cod (Gadus morhua).

    PubMed

    Andersen, Øivind; Johnsen, Hanne; De Rosa, Maria Cristina; Præbel, Kim; Stjelja, Suzana; Kirubakaran, Tina Graceline; Pirolli, Davide; Jentoft, Sissel; Fevolden, Svein-Erik

    2015-08-01

    The synaptophysin (SYP) family comprises integral membrane proteins involved in vesicle-trafficking events, but the physiological function of several members has been enigmatic for decades. The presynaptic SYP protein controls neurotransmitter release, while SYP-like 2 (SYPL2) contributes to maintain normal Ca(2+)-signaling in the skeletal muscles. The polymorphic pantophysin (Pan I) of Atlantic cod shows strong genetic divergence between stationary and migratory populations, which seem to be adapted to local environmental conditions. We have investigated the functional involvement of Pan I in the different ecotypes by analyzing the 1) phylogeny, 2) spatio-temporal gene expression, 3) structure-function relationship of the Pan I(A) and I(B) protein variants, and 4) linkage to rhodopsin (rho) recently proposed to be associated with different light sensitivities in Icelandic populations of Atlantic cod. We searched for SYP family genes in phylogenetic key species and identified a single syp-related gene in three invertebrate chordates, while four members, Syp, Sypl1, Sypl2 and synaptoporin (Synpr), were found in tetrapods, Comoran coelacanth and spotted gar. Teleost fish were shown to possess duplicated syp, sypl2 and synpr genes of which the sypl2b paralog is identical to Pan I. The ubiquitously expressed cod Pan I codes for a tetra-spanning membrane protein possessing five amino acid substitutions in the first intravesicular loop, but only minor structural differences were shown between the allelic variants. Despite sizable genomic distance (>2.5 Mb) between Pan I and rho, highly significant linkage disequilibrium was found by genotyping shallow and deep water juvenile settlers predominated by the Pan I(A)-rho(A) and Pan I(B)-rho(B) haplotypes, respectively. However, the predicted rhodopsin protein showed no amino acid changes, while multiple polymorphic sites in the upstream region might affect the gene expression and pigment levels in stationary and migratory cod

  11. Low impact of exposure to environmentally relevant doses of 226Ra in Atlantic cod (Gadus morhua) embryonic cells.

    PubMed

    Olsvik, Pål A; Berntssen, Marc H G; Hylland, Ketil; Eriksen, Dag Ø; Holen, Elisabeth

    2012-07-01

    The aim of this study was to investigate whether (226)Ra, a radionuclide present in produced water from oil platforms in the North Sea and other offshore drilling areas, could affect vulnerable early life stages of Atlantic cod (Gadus morhua). Blastula-stage embryonic cells (EC) from fertilized eggs of Atlantic cod were isolated and exposed to environmental relevant concentrations of (226)Ra and transcription of selected genes quantified. The results showed a weak, but significant up-regulation of GPx3 and HSP70 transcripts after 48 h of exposure to 2.11 Bq/L. In EC exposed to three (226)Ra concentrations (2.11, 23 and 117 Bq/L) for 12 h, metallothionein, HSP90AA, thioredoxin and caspase 8 were significantly up-regulated in cells exposed to 117 Bq/L, whereas thioredoxin was also significantly up-regulated in EC exposed to 23 Bq/L. When EC were exposed to the same (226)Ra concentrations for 48 h, only heme oxygenase was significantly up-regulated in the 23 Bq/L exposure group. The results suggest that environmentally relevant activities of (226)Ra may induce oxidative stress and apoptosis in fish ECs. Exposure of Atlantic cod EC to Cd, selected as a model toxicant, supported the ability of EC around blastula stage to respond to toxicants by altered transcription. Due to dilution, environmentally relevant concentrations of radionuclides present in produced water would be expected to pose a minor threat to early life stages of fish. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Thermal habitat constraints on zooplankton species associated with Atlantic cod (Gadus morhua) on the US Northeast Continental Shelf

    NASA Astrophysics Data System (ADS)

    Friedland, Kevin D.; Kane, Joe; Hare, Jonathan A.; Lough, R. Gregory; Fratantoni, Paula S.; Fogarty, Michael J.; Nye, Janet A.

    2013-09-01

    The US Northeast Continental Shelf is experiencing a period of increasing temperature levels and range, which impacts the quantity of thermal habitats within the ecosystem. With increasing temperatures, the amount of warmer, surface water thermal habitats (16-27 °C) has increased while there has been a reciprocal decline in cooler water habitats (5-15 °C). These cooler water habitats are the most abundant and comprise the core habitats of the ecosystem. The coldest thermal habitats (1-4 °C), however, have increased slightly in amount or have remained constant, reflecting a discontinuity in the progression of warming along a latitudinal gradient. This discontinuity may be the result of recent changes in the circulation of water masses in the northern Gulf of Maine, potentially associated with the Labrador Current. The contraction of core thermal habitats appears to have had biological consequences on multiple trophic levels. In particular, two zooplankton species associated with the larval feeding of Atlantic cod, Gadus morhua, have declined in abundance in the same areas where cod populations have exhibited continually poor recruitment. The zooplankton species group Pseudocalanus spp., which is associated with winter-spawning cod, has declined on Georges Bank and in the Eastern Gulf of Maine. The zooplankton Centropages typicus has declined in the Gulf of Maine during late summer into fall, potentially affecting spring-spawning cod in that area. These observations are consistent with the hypothesis that portions of the population complex of cod have lower reproductive output due to changes in zooplankton abundance, which we associate with the distribution of temperatures within the ecosystem.

  13. Skeletal muscle growth dynamics and the influence of first-feeding diet in Atlantic cod larvae (Gadus morhua L.)

    PubMed Central

    Vo, Tu A.; Galloway, Trina F.; Bardal, Tora; Halseth, Christine K.; Øie, Gunvor

    2016-01-01

    ABSTRACT Dynamics between hypertrophy (increase in cell size) and hyperplasia (increase in cell numbers) of white and red muscle in relation to body size [standard length (SL)], and the influence of the first-feeding diets on muscle growth were investigated in Atlantic cod larvae (Gadus morhua). Cod larvae were fed copepod nauplii or rotifers of different nutritional qualities from 4 to 29 days post hatching (dph), Artemia nauplii from 20 to 40 dph and a formulated diet from 36 to 60 dph. The short period of feeding with cultivated copepod nauplii had a positive effect on both muscle hyperplasia and hypertrophy after the copepod/rotifer phase (19 dph), and a positive long term effect on muscle hypertrophy (60 dph). The different nutritional qualities of rotifers did not significantly affect muscle growth. We suggest here a model of the dynamics between hyperplasia and hypertrophy of red and white muscle fibre cells in relation to cod SL (4 to 30 mm), where the different red and white muscle growth phases clearly coincided with different metamorphosis stages in cod larvae. These shifts could be included as biomarkers for the different stages of development during metamorphosis. The main dietary muscle effect was that hypertrophic growth of red muscle fibres was stronger in cod larvae that were fed copepods than in larvae that were fed rotifers, both in relation to larval age and size. Red muscle fibres are directly involved in larval locomotory performance, but may also play an important role in the larval myogenesis. This can have a long term effect on growth potential and fish performance. PMID:27612513

  14. Skeletal muscle growth dynamics and the influence of first-feeding diet in Atlantic cod larvae (Gadus morhua L.).

    PubMed

    Vo, Tu A; Galloway, Trina F; Bardal, Tora; Halseth, Christine K; Øie, Gunvor; Kjørsvik, Elin

    2016-11-15

    Dynamics between hypertrophy (increase in cell size) and hyperplasia (increase in cell numbers) of white and red muscle in relation to body size [standard length (SL)], and the influence of the first-feeding diets on muscle growth were investigated in Atlantic cod larvae (Gadus morhua). Cod larvae were fed copepod nauplii or rotifers of different nutritional qualities from 4 to 29 days post hatching (dph), Artemia nauplii from 20 to 40 dph and a formulated diet from 36 to 60 dph. The short period of feeding with cultivated copepod nauplii had a positive effect on both muscle hyperplasia and hypertrophy after the copepod/rotifer phase (19 dph), and a positive long term effect on muscle hypertrophy (60 dph). The different nutritional qualities of rotifers did not significantly affect muscle growth. We suggest here a model of the dynamics between hyperplasia and hypertrophy of red and white muscle fibre cells in relation to cod SL (4 to 30 mm), where the different red and white muscle growth phases clearly coincided with different metamorphosis stages in cod larvae. These shifts could be included as biomarkers for the different stages of development during metamorphosis. The main dietary muscle effect was that hypertrophic growth of red muscle fibres was stronger in cod larvae that were fed copepods than in larvae that were fed rotifers, both in relation to larval age and size. Red muscle fibres are directly involved in larval locomotory performance, but may also play an important role in the larval myogenesis. This can have a long term effect on growth potential and fish performance.

  15. Effects of amino acid supplementations on metabolic and physiological parameters in Atlantic cod (Gadus morhua) under stress.

    PubMed

    Herrera, Marcelino; Herves, María Antonia; Giráldez, Inmaculada; Skar, Kristin; Mogren, Hanne; Mortensen, Atle; Puvanendran, Velmurugu

    2017-04-01

    The effects of tryptophan (Trp) and phenylalanine (Phe) diet supplementation on the stress and metabolism of the Atlantic cod have been studied. Fish were fed diet supplemented with Trp or Phe or control diet for 1 week. At the end of the feeding trial, fish were subjected to air exposure or heat shock. Following samples of blood, liver and muscle were taken from the fish and were analyzed for stress and metabolic indicators. After an air exposure, plasma cortisol levels in fish fed with Trp and Phe diets were lower compared to the fish fed the control diet. Diets containing both amino acids increased significantly the liver transaminase activities in juvenile cod. During thermal stress, high Trp contents had significant effects on fructose biphosphatase activity though Phe did not. Overall, activities of glucose 6-phosphate dehydrogenase, pyruvate kinase, and phosphofructokinase increased significantly for both amino acid diets. For the thermal stress, fish had the highest values of those activities for the 3Trp diet. Trp content in the diet had significant effects on the transaminase activity in muscle during air stress compared to fish fed control and Phe diets. Muscle alanine transaminase activity for thermal stress in fish fed any diet was not significantly different from the control. Both Trp and Phe supplementations reduced the stress markers in the cod; hence, they could be used as additives for the stress attenuation. However, they also raised the activity of key enzymes in glycolysis and gluconeogenesis, mainly the Trp diets.

  16. Multiple linked β and α globin genes in Atlantic cod: A PCR based strategy of genomic exploration.

    PubMed

    Halldórsdóttir, Katrín; Arnason, Einar

    2009-01-01

    Allozyme variation in Atlantic cod hemoglobins shows various signs of natural selection. We report a genomic exploration of globin genes in this non-model organism. Applying a PCR based strategy with a strict criterion of phylogenetically informative sites we estimate the number of linked β and α globin genes. We estimate PCR error rate by PCR of cloned DNA and recloning and by analysis of singleton variable sites among clones. Based on the error rate we exclude variable sites so that the remaining variation meets successively stricter criteria of doubleton and triplet variable site. Applying these criteria we find ten clusters of linked β/α globin genes in the genome of Atlantic cod. Six variable amino acid changes in both genes were found in linkage disequilibrium with silent nucleotide substitutions. A phylogenetic tree, based on our strictly phylogenetically informative sites among 57 clones from 19 individuals, is split into two major branches by an amino acid change in a β gene. This change is supported by extensive linkage disequilibrium between the amino acid change and numerous other phylogenetically informative silent nucleotide sites. The different gene sets in the genome may represent different loci encoding different globins and/or allelic variation at some loci.

  17. Nucleotide variation and balancing selection at the Ckma gene in Atlantic cod: analysis with multiple merger coalescent models.

    PubMed

    Árnason, Einar; Halldórsdóttir, Katrín

    2015-01-01

    High-fecundity organisms, such as Atlantic cod, can withstand substantial natural selection and the entailing genetic load of replacing alleles at a number of loci due to their excess reproductive capacity. High-fecundity organisms may reproduce by sweepstakes leading to highly skewed heavy-tailed offspring distribution. Under such reproduction the Kingman coalescent of binary mergers breaks down and models of multiple merger coalescent are more appropriate. Here we study nucleotide variation at the Ckma (Creatine Kinase Muscle type A) gene in Atlantic cod. The gene shows extreme differentiation between the North (Canada, Greenland, Iceland, Norway, Barents Sea) and the South (Faroe Islands, North-, Baltic-, Celtic-, and Irish Seas) with FST > 0.8 between regions whereas neutral loci show no differentiation. This is evidence of natural selection. The protein sequence is conserved by purifying selection whereas silent and non-coding sites show extreme differentiation. The unfolded site-frequency spectrum has three modes, a mode at singleton sites and two high frequency modes at opposite frequencies representing divergent branches of the gene genealogy that is evidence for balancing selection. Analysis with multiple-merger coalescent models can account for the high frequency of singleton sites and indicate reproductive sweepstakes. Coalescent time scales vary with population size and with the inverse of variance in offspring number. Parameter estimates using multiple-merger coalescent models show that times scales are faster than under the Kingman coalescent.

  18. Nucleotide variation and balancing selection at the Ckma gene in Atlantic cod: analysis with multiple merger coalescent models

    PubMed Central

    Halldórsdóttir, Katrín

    2015-01-01

    High-fecundity organisms, such as Atlantic cod, can withstand substantial natural selection and the entailing genetic load of replacing alleles at a number of loci due to their excess reproductive capacity. High-fecundity organisms may reproduce by sweepstakes leading to highly skewed heavy-tailed offspring distribution. Under such reproduction the Kingman coalescent of binary mergers breaks down and models of multiple merger coalescent are more appropriate. Here we study nucleotide variation at the Ckma (Creatine Kinase Muscle type A) gene in Atlantic cod. The gene shows extreme differentiation between the North (Canada, Greenland, Iceland, Norway, Barents Sea) and the South (Faroe Islands, North-, Baltic-, Celtic-, and Irish Seas) with FST > 0.8 between regions whereas neutral loci show no differentiation. This is evidence of natural selection. The protein sequence is conserved by purifying selection whereas silent and non-coding sites show extreme differentiation. The unfolded site-frequency spectrum has three modes, a mode at singleton sites and two high frequency modes at opposite frequencies representing divergent branches of the gene genealogy that is evidence for balancing selection. Analysis with multiple-merger coalescent models can account for the high frequency of singleton sites and indicate reproductive sweepstakes. Coalescent time scales vary with population size and with the inverse of variance in offspring number. Parameter estimates using multiple-merger coalescent models show that times scales are faster than under the Kingman coalescent. PMID:25755922

  19. Prolonged SDA and reduced digestive efficiency under elevated CO2 may explain reduced growth in Atlantic cod (Gadus morhua).

    PubMed

    Tirsgaard, Bjørn; Moran, Damian; Steffensen, John F

    2015-01-01

    Land-based aquaculture systems expose fish to elevated dissolved CO2 levels, a factor that is correlated with reduced growth, feed conversion efficiency and body condition index. The physiological basis underlying the pathological effects of environmental hypercapnia is poorly understood, in particular for marine fish species. We investigated whether changes in energy expenditure and the specific dynamic action (SDA) of digestion and assimilation could account for the lower growth of adult Atlantic cod (Gadus morhua) under environmental hypercapnia. Fish acclimated to a partial pressure of 800 μatm CO2 (0.6 mmHg, 1.5 mg/L) and 9200 μatm CO2 (7 mmHg, 18.7 mg/L) exhibited no difference in maintenance metabolic rates, which concurs with previous research for this species and other fish species. At 9200 μatm CO2 Atlantic cod had a significantly diminished (14%) maximum aerobic capacity. While hypercapnia did not affect the amount of oxygen required for the SDA process, it did prolong the SDA duration by 23%. The longer SDA process time may offer an explanation for the observation of lower feed intake, growth and condition factor in long-term hypercapnia studies. Comparison of aerobic scope and cardiac performance during digestion suggested that reduced oxygen delivery capacity under hypercapnia could be one mechanism by which CO2 prolongs SDA, although our results could not definitively demonstrate this effect. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Polymorphism, selection and tandem duplication of transferrin genes in Atlantic cod (Gadus morhua) - Conserved synteny between fish monolobal and tetrapod bilobal transferrin loci

    PubMed Central

    2011-01-01

    Background The two homologous iron-binding lobes of transferrins are thought to have evolved by gene duplication of an ancestral monolobal form, but any conserved synteny between bilobal and monolobal transferrin loci remains unexplored. The important role played by transferrin in the resistance to invading pathogens makes this polymorphic gene a highly valuable candidate for studying adaptive divergence among local populations. Results The Atlantic cod genome was shown to harbour two tandem duplicated serum transferrin genes (Tf1, Tf2), a melanotransferrin gene (MTf), and a monolobal transferrin gene (Omp). Whereas Tf1 and Tf2 were differentially expressed in liver and brain, the Omp transcript was restricted to the otoliths. Fish, chicken and mammals showed highly conserved syntenic regions in which monolobal and bilobal transferrins reside, but contrasting with tetrapods, the fish transferrin genes are positioned on three different linkage groups. Sequence alignment of cod Tf1 cDNAs from Northeast (NE) and Northwest (NW) Atlantic populations revealed 22 single nucleotide polymorphisms (SNP) causing the replacement of 16 amino acids, including eight surface residues revealed by the modelled 3D-structures, that might influence the binding of pathogens for removal of iron. SNP analysis of a total of 375 individuals from 14 trans-Atlantic populations showed that the Tf1-NE variant was almost fixed in the Baltic cod and predominated in the other NE Atlantic populations, whereas the NW Atlantic populations were more heterozygous and showed high frequencies of the Tf-NW SNP alleles. Conclusions The highly conserved synteny between fish and tetrapod transferrin loci infers that the fusion of tandem duplicated Omp-like genes gave rise to the modern transferrins. The multiple nonsynonymous substitutions in cod Tf1 with putative structural effects, together with highly divergent allele frequencies among different cod populations, strongly suggest evidence for positive

  1. Transcriptional effects on glutathione S-transferases in first feeding Atlantic cod (Gadus morhua) larvae exposed to crude oil.

    PubMed

    Olsvik, P A; Nordtug, T; Altin, D; Lie, K K; Overrein, I; Hansen, B H

    2010-05-01

    Polycyclic aromatic hydrocarbons (PAHs) and other oil compounds are known to induce stress and impact health of marine organisms. Water-soluble fractions of oil contain components known to induce glutathione S-transferases (GSTs), one of the major classes of phase II detoxifying enzymes present in essentially all eukaryotic organisms. In this study, the transcriptional responses of six GSTs (GST pi, GST mu, GST omega, GST theta, GSY zeta and GST kappa) were examined in early larvae of Atlantic cod Gadus morhua exposed to five concentrations of dispersed oil (containing oil droplets and water-soluble fraction) and water-soluble fractions (WSF) of oil. When Atlantic cod larvae were exposed to WSF (containing 1.31+/-0.31microg summation PAH/L for 4 days), expression of GSTM3 and GSTO1 was significantly increased, whereas no differences in GST expression were observed in larvae exposed to a corresponding 50% lower amount of dispersed oil (containing 0.36+/-0.10 microg summation PAH/L for 4 days). The study suggest that although the oil clearly had severe negative effects on the larvae (i.e. concentration-dependent lethality and growth reduction), only minor effects on GST transcription could be observed using RNA obtained from pooled whole-larvae homogenates. This result indicates that the expression of these important detoxification enzymes is only moderately inducible at such an early developmental stage either reflecting low tolerance of cod larvae to dispersed oil or alternatively that using whole-larvae homogenates may have masked tissue-specific mRNA induction.

  2. Global transcriptome analysis identifies regulated transcripts and pathways activated during oogenesis and early embryogenesis in atlantic cod

    PubMed Central

    Kleppe, Lene; Edvardsen, Rolf Brudvik; Furmanek, Tomasz; Taranger, Geir Lasse; Wargelius, Anna

    2014-01-01

    The molecular mechanisms underlying oogenesis and maternally controlled embryogenesis in fish are not fully understood, especially in marine species. Our aim was to study the egg and embryo transcriptome during oogenesis and early embryogenesis in Atlantic cod. Follicles from oogenesis stages (pre-, early-, and late-vitellogenic), ovulated eggs, and two embryonic stages (blastula, gastrula) were collected from broodstock fish and fertilized eggs. Gene expression profiles were measured in a 44 K oligo microarray consisting of 23,000 cod genes. Hundreds of differentially expressed genes (DEGs) were identified in the follicle stages investigated, implicating a continuous accumulation and degradation of polyadenylated transcripts throughout oogenesis. Very few DEGs were identified from ovulated egg to blastula, showing a more stable maternal RNA pool in early embryonic stages. The highest induction of expression was observed between blastula and gastrula, signifying the onset of zygotic transcription. During early vitellogenesis, several of the most upregulated genes are linked to nervous system signaling, suggesting increasing requirements for ovarian synaptic signaling to stimulate the rapid growth of oocytes. Highly upregulated genes during late vitellogenesis are linked to protein processing, fat metabolism, osmoregulation, and arrested meiosis. One of the genes with the highest upregulation in the ovulated egg is involved in oxidative phosphorylation, reflecting increased energy requirements during fertilization and the first rapid cell divisions of early embryogenesis. In conclusion, this study provides a large-scale presentation of the Atlantic cod's maternally controlled transcriptome in ovarian follicles through oogenesis, ovulated eggs, and early embryos. Mol. Reprod. Dev. 81: 619–635, 2014. © 2014 Wiley Periodicals, Inc. PMID:24687555

  3. Will you swim into my parlour? In situ observations of Atlantic cod (Gadus morhua) interactions with baited pots, with implications for gear design

    PubMed Central

    Walsh, Philip; Favaro, Brett

    2017-01-01

    Pots (also known as traps) are baited fishing gears widely used in commercial fisheries, and are being considered as a tool for harvesting Atlantic cod (Gadus morhua) in Newfoundland and Labrador, Canada. Pots produce lower environmental impacts than many other fishing gears, but they will only be a viable fishing strategy if they are efficient and selective at catching their target species. To study the behaviour of cod in and around pots, and how those behaviours affect pot efficiency, we used long-duration underwater video cameras to assess two models of cod pot deployed in the nearshore waters of Fogo Island, NL. We examined the number of cod that approached the pot, the number and proportion that successfully completed entries into the pot openings, and the number that exited, and related these factors to the direction of water movement. We observed very few entry attempts relative to the number of approaches by cod, and only 22% of all entry attempts were successful. We observed that 50% of approaches, 70% of entry attempts, and 73% of successful entrances occurred against the current, and 25% of cod were able to exit the pot following capture. Based on our observations, we suggest that future cod pots should have a greater number of entrances, or a mechanism to ensure that entrances rotate in line with the current, in order to maximize their catch efficiency for cod. PMID:28194312

  4. Will you swim into my parlour? In situ observations of Atlantic cod (Gadus morhua) interactions with baited pots, with implications for gear design.

    PubMed

    Meintzer, Phillip; Walsh, Philip; Favaro, Brett

    2017-01-01

    Pots (also known as traps) are baited fishing gears widely used in commercial fisheries, and are being considered as a tool for harvesting Atlantic cod (Gadus morhua) in Newfoundland and Labrador, Canada. Pots produce lower environmental impacts than many other fishing gears, but they will only be a viable fishing strategy if they are efficient and selective at catching their target species. To study the behaviour of cod in and around pots, and how those behaviours affect pot efficiency, we used long-duration underwater video cameras to assess two models of cod pot deployed in the nearshore waters of Fogo Island, NL. We examined the number of cod that approached the pot, the number and proportion that successfully completed entries into the pot openings, and the number that exited, and related these factors to the direction of water movement. We observed very few entry attempts relative to the number of approaches by cod, and only 22% of all entry attempts were successful. We observed that 50% of approaches, 70% of entry attempts, and 73% of successful entrances occurred against the current, and 25% of cod were able to exit the pot following capture. Based on our observations, we suggest that future cod pots should have a greater number of entrances, or a mechanism to ensure that entrances rotate in line with the current, in order to maximize their catch efficiency for cod.

  5. Molecular Evidence that Only Two Opsin Subfamilies, the Blue Light- (SWS2) and Green Light-Sensitive (RH2), Drive Color Vision in Atlantic Cod (Gadus morhua)

    PubMed Central

    Søviknes, Anne Mette; Drivenes, Øyvind; Helvik, Jon Vidar

    2014-01-01

    Teleosts show a great variety in visual opsin complement, due to both gene duplication and gene loss. The repertoire ranges from one subfamily of visual opsins (scotopic vision) including rod opsin only retinas seen in many deep-sea species to multiple subfamilies of visual opsins in some pelagic species. We have investigated the opsin repertoire of Atlantic cod (Gadus morhua) using information in the recently sequenced cod genome and found that despite cod not being a deep sea species it lacks visual subfamilies sensitive towards the most extreme parts of the light spectra representing UV and red light. Furthermore, we find that Atlantic cod has duplicated paralogs of both blue-sensitive SWS2 and green-sensitive RH2 subfamilies, with members belonging to each subfamily linked in tandem within the genome (two SWS2-, and three RH2A genes, respectively). The presence of multiple cone opsin genes indicates that there have been duplication events in the cod ancestor SWS2 and RH2 opsins producing paralogs that have been retained in Atlantic. Our results are supported by expressional analysis of cone opsins, which further revealed an ontogenetic change in the array of cone opsins expressed. These findings suggest life stage specific programs for opsin regulation which could be linked to habitat changes and available light as the larvae is transformed into an early juvenile. Altogether we provide the first molecular evidence for color vision driven by only two families of cone opsins due to gene loss in a teleost. PMID:25551396

  6. Molecular evidence that only two opsin subfamilies, the blue light- (SWS2) and green light-sensitive (RH2), drive color vision in Atlantic cod (Gadus morhua).

    PubMed

    Valen, Ragnhild; Edvardsen, Rolf Brudvik; Søviknes, Anne Mette; Drivenes, Øyvind; Helvik, Jon Vidar

    2014-01-01

    Teleosts show a great variety in visual opsin complement, due to both gene duplication and gene loss. The repertoire ranges from one subfamily of visual opsins (scotopic vision) including rod opsin only retinas seen in many deep-sea species to multiple subfamilies of visual opsins in some pelagic species. We have investigated the opsin repertoire of Atlantic cod (Gadus morhua) using information in the recently sequenced cod genome and found that despite cod not being a deep sea species it lacks visual subfamilies sensitive towards the most extreme parts of the light spectra representing UV and red light. Furthermore, we find that Atlantic cod has duplicated paralogs of both blue-sensitive SWS2 and green-sensitive RH2 subfamilies, with members belonging to each subfamily linked in tandem within the genome (two SWS2-, and three RH2A genes, respectively). The presence of multiple cone opsin genes indicates that there have been duplication events in the cod ancestor SWS2 and RH2 opsins producing paralogs that have been retained in Atlantic. Our results are supported by expressional analysis of cone opsins, which further revealed an ontogenetic change in the array of cone opsins expressed. These findings suggest life stage specific programs for opsin regulation which could be linked to habitat changes and available light as the larvae is transformed into an early juvenile. Altogether we provide the first molecular evidence for color vision driven by only two families of cone opsins due to gene loss in a teleost.

  7. Functional genomic analysis of the response of Atlantic cod (Gadus morhua) spleen to the viral mimic polyriboinosinic polyribocytidylic acid (pIC).

    PubMed

    Rise, Matthew L; Hall, Jennifer; Rise, Marlies; Hori, Tiago; Gamperl, A Kurt; Kimball, Jennifer; Hubert, Sophie; Bowman, Sharen; Johnson, Stewart C

    2008-01-01

    In order to improve our understanding of how Atlantic cod (Gadus morhua) respond to viruses, we characterized immune-related gene expression in spleen tissues following stimulation with a synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid (pIC). We used reciprocal suppression subtractive hybridization (SSH) cDNA libraries and quantitative RTPCR (QPCR) to identify and quantify pIC-responsive transcripts. A total of 3874 expressed sequence tags (ESTs) were generated from SSH libraries enriched for genes responsive to pIC. Thirteen immune-relevant genes from the libraries were subjected to QPCR. Genes confirmed as up-regulated by pIC included interferon stimulated gene 15, a small inducible cytokine, interferon regulatory factors (1, 7, and 10), MHC class I, viperin, and ATP-dependent helicase LGP2. Alpha-1-microglobulin (bikunin) was down-regulated, suggesting that pIC may suppress the acute phase response. Since the SSH libraries built for this study identified genes involved in the antiviral response, they are important resources for studying the responses of Atlantic cod to viruses. Evidence is provided for the existence of a RIG-I-like RNA helicase viral recognition pathway in Atlantic cod. Taken together, our data show that Atlantic cod can recognize double-stranded RNA and mount a rapid and potent interferon pathway response that is similar to that observed in other fish species and higher vertebrates.

  8. Evidence from data storage tags for the presence of lunar and semilunar behavioral cycles in spawning Atlantic cod

    USGS Publications Warehouse

    Grabowski, Timothy B.; McAdam, Bruce J.; Thorsteinsson, Vilhjalmur; Marteinsdóttir, Gudrún

    2015-01-01

    Understanding the environmental processes determining the timing and success of reproduction is of critical importance to developing effective management strategies of marine fishes. Unfortunately it has proven difficult to comprehensively study the reproductive behavior of broadcast-spawning fishes. The use of electronic data storage tags (DSTs) has the potential to provide insights into the behavior of fishes. These tags allow for data collection over relatively large spatial and temporal scales that can be correlated to predicted environmental conditions and ultimately be used to refine predictions of year class strength. In this paper we present data retrieved from DSTs demonstrating that events putatively identified as Atlantic cod spawning behavior is tied to a lunar cycle with a pronounced semi-lunar cycle within it. Peak activity occurs around the full and new moon with no evidence of relationship with day/night cycles.

  9. Effects of pre-slaughter stress on proteolytic enzyme activities and muscle quality of farmed Atlantic cod (Gadus morhua).

    PubMed

    Hultmann, Lisbeth; Phu, Tran Minh; Tobiassen, Torbjørn; Aas-Hansen, Øyvind; Rustad, Turid

    2012-10-01

    Farmed Atlantic cod were subjected to a combination of stressors in a holding tank before being killed, pre rigor filleted and stored in ice. At slaughter, a higher level of stress was confirmed by blood physiology analyses. This was further associated with significantly reduced muscle pH and somewhat elevated muscle collagenase-like activity in the stressed fish, whereas no differences in cathepsin-like activities were found. After 5 days of iced storage, the stressed fish had significantly lower water holding capacity, reduced hardness and yellowish colour compared to the control group, and no differences in the other parameters investigated. Independent of pre-slaughter stress, the activities of cathepsin B- and B/L-like enzymes increased and activities of cathepsin D/E- and collagenase-like enzymes decreased with storage.

  10. An investigation of appetite-related peptide transcript expression in Atlantic cod (Gadus morhua) brain following a Camelina sativa meal-supplemented feeding trial.

    PubMed

    Tuziak, Sarah M; Rise, Matthew L; Volkoff, Hélène

    2014-10-25

    Camelina sativa is a hardy oilseed crop with seeds that contain high levels of ω3 polyunsaturated fatty acids and protein, which are critical components of fish feed. Camelina might thus be used as a cheaper and more sustainable supplement to fish-based products in aquaculture. Atlantic cod, Gadus morhua, is a species of interest in the aquaculture industry due to a decrease in wild populations and subsequent collapse of some cod fisheries. As cod are carnivorous fish, it is necessary to determine how this species physiologically tolerates plant-based diets. In this study, juvenile Atlantic cod were subjected to 13 weeks of either 15 or 30% camelina meal (CM)-supplemented diets or a control fish meal feed. Growth and food intake were evaluated and the mRNA expression of appetite-related hormones [pro-melanin-concentrating hormone (pmch), hypocretin (synonym: orexin, hcrt), neuropeptide Y (npy) and cocaine- and amphetamine-regulated transcript (cart)] was assessed using quantitative real-time PCR in brain regions related to food intake regulation (telencephalon/preoptic area, optic tectum/thalamus and hypothalamus). CM inclusion diets caused decreases in both growth and food intake in Atlantic cod. Optic tectum pmch transcript expression was significantly higher in fish fed the 30% CM diet compared to fish fed the 15% CM diet. In the hypothalamus, compared to fish fed the control diet, hcrt expression was significantly higher in fish fed the 30% CM diet, while npy transcript expression was significantly higher in fish fed the 15% CM diet. cart mRNA expression was not affected by diet in any brain region. Further studies are needed to determine which factors (e.g. anti-nutritional factors, palatability and nutritional deficits) contribute to reduced feed intake and growth, as well as the maximum CM inclusion level that does not negatively influence feed intake, growth rate and the transcript expression of appetite-related factors in Atlantic cod.

  11. Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae - can we identify the underlying factors?

    PubMed

    Karlsen, Ørjan; van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trina F; Kjørsvik, Elin; Hamre, Kristin

    2015-01-01

    The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were conducted in order to identify the underlying factors for this phenomenon. In the first experiment (Exp-1), groups of cod larvae were fed either (a) natural zooplankton, mainly copepods, increasing the size of prey as the larvae grew or (b) enriched rotifers followed by Artemia (the intensive group). In the second experiment (Exp-2), two groups of larvae were fed as in Exp-1, while a third group was fed copepod nauplii (approximately the size of rotifers) throughout the larval stage. In both experiments, growth was not significantly different between the groups during the first three weeks after hatching, but from the last part of the rotifer feeding period and onwards, the growth of the larvae fed copepods was higher than that of the intensive group. In Exp-2, the growth was similar between the two copepod groups during the expeimental period, indicating that nutrient composition, not prey size caused the better growth on copepods. Analyses of the prey showed that total fatty acid composition and the ratio of phospholipids to total lipids was slightly different in the prey organisms, and that protein, taurine, astaxanthin and zinc were lower on a dry weight basis in rotifers than in copepods. Other measured nutrients as DHA, all analysed vitamins, manganese, copper and selenium were similar or higher in the rotifers. When compared to the present knowledge on nutrient requirements, protein and taurine appeared to be the most likely limiting nutrients for growth in cod larvae fed rotifers and Artemia. Larvae fed rotifers/Artemia had a higher whole body lipid content than larvae fed copepods at the end of the experiment (stage 5) after the fish had been fed the same formulated diet for approximately 2 weeks.

  12. Is chemically dispersed oil more toxic to Atlantic cod (Gadus morhua) larvae than mechanically dispersed oil? A transcriptional evaluation

    PubMed Central

    2012-01-01

    Background The use of dispersants can be an effective way to deal with acute oil spills to limit environmental damage, however very little is known about whether chemically dispersed oil have the same toxic effect on marine organisms as mechanically dispersed oil. We exposed Atlantic cod larvae to chemically and mechanically dispersed oil for four days during the first-feeding stage of development, and collected larvae at 14 days post hatch for transcriptional analysis. A genome-wide microarray was used to screen for effects and to assess whether molecular responses to chemically and mechanically dispersed oil were similar, given the same exposure to oil (droplet distribution and concentration) with and without the addition of a chemical dispersant (Dasic NS). Results Mechanically dispersed oil induced expression changes in almost three times as many transcripts compared to chemically dispersed oil (fold change >+/−1.5). Functional analyses suggest that chemically dispersed oil affects partly different pathways than mechanically dispersed oil. By comparing the alteration in gene transcription in cod larvae exposed to the highest concentrations of either chemically or mechanically dispersed oil directly, the chemically dispersed oil affected transcription of genes involved nucleosome regulation, i.e. genes encoding proteins participating in DNA replication and chromatin formation and regulation of cell proliferation, whereas the mechanically dispersed oil most strongly affected genes encoding proteins involved in proteasome-mediated protein degradation. Cyp1a was the transcript that was most strongly affected in both exposure groups, with a 60-fold induction in the two high-exposure groups according to the RT-qPCR data, but no significant difference in transcriptional levels was observed between the two treatments. Conclusions In summary, dispersants do not appear to add to the magnitude of transcriptional responses of oil compounds but rather appear to lower or

  13. Oil droplet fouling and differential toxicokinetics of polycyclic aromatic hydrocarbons in embryos of Atlantic haddock and cod

    PubMed Central

    Sørhus, Elin; Nordtug, Trond; Incardona, John P.; Linbo, Tiffany L.; Giovanetti, Laura; Karlsen, Ørjan; Meier, Sonnich

    2017-01-01

    The impact of crude oil pollution on early life stages (ELS) of fish, including larvae and embryos, has received considerable attention in recent years. Of the organic components present in crude oil, polycyclic aromatic hydrocarbons (PAHs) are considered the main class of compounds responsible for toxic effects in marine organisms. Although evidence suggests that they are more toxic, alkylated PAHs remain much less studied than their unsubstituted congeners. Recently, it was established that embryos of Atlantic haddock (Melanogrammus aeglefinus) are particularly sensitive to dispersed crude oil, and it was hypothesized that this was caused by direct interaction with crude oil droplets, which adhered to the chorion of exposed embryos. Such a phenomenon would increase the potential for uptake of less water-soluble compounds, including alkylated PAHs. In the current study, we compared the uptake of parent and alkylated PAHs in Atlantic cod (Gadus morhua) and haddock embryos exposed to dispersed crude oil at a range of environmentally relevant concentrations (10–600 μg oil/liter seawater). Although the species are biologically very similar, the cod chorion does not become fouled with oil droplets, even when the two species are exposed to dispersions of crude oil droplets under similar conditions. A close correlation between the degree of fouling and toxicological response (heart defects, craniofacial malformation) was observed. Oil droplet fouling in haddock led to both quantitative and qualitative differences in PAH uptake. Finally, kinetic data on a large suite of PAHs showed differential elimination, suggesting differential metabolism of unsubstituted versus alkylated compounds. PMID:28678887

  14. Synergies between climate and management for Atlantic cod fisheries at high latitudes.

    PubMed

    Kjesbu, Olav Sigurd; Bogstad, Bjarte; Devine, Jennifer A; Gjøsæter, Harald; Howell, Daniel; Ingvaldsen, Randi B; Nash, Richard D M; Skjæraasen, Jon Egil

    2014-03-04

    The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and positive changes in population size, this invariably leads to questions about whether favorable climatic conditions or good management (or both) were responsible. The Barents Sea cod (Gadus morhua) stock has recently increased markedly and the spawning stock biomass is now at an unprecedented high. We identify the crucial social and environmental factors that made this unique growth possible. The relationship between vital rates of Barents Sea cod stock productivity (recruitment, growth, and mortality) and environment is investigated, followed by simulations of population size under different management scenarios. We show that the recent sustained reduction in fishing mortality, facilitated by the implementation of a "harvest control rule," was essential to the increase in population size. Simulations show that a drastic reduction in fishing mortality has resulted in a doubling of the total population biomass compared with that expected under the former management regime. However, management alone was not solely responsible. We document that prevailing climate, operating through several mechanistic links, positively reinforced management actions. Heightened temperature resulted in an increase in the extent of the suitable feeding area for Barents Sea cod, likely offering a release from density-dependent effects (for example, food competition and cannibalism) through prolonged overlap with prey and improved adult stock productivity. Management and climate may thus interact to give a positive outlook for exploited high-latitude marine resources.

  15. Melanin-concentrating hormone (MCH) and gonadotropin-releasing hormones (GnRH) in Atlantic cod, Gadus morhua: tissue distributions, early ontogeny and effects of fasting.

    PubMed

    Tuziak, Sarah M; Volkoff, Hélène

    2013-12-01

    Melanin-concentrating hormone (MCH) is classically known for its role in regulating teleost fish skin color change for environmental adaptation. Recent evidence suggests that MCH also has appetite-stimulating properties. The gonadotropin-releasing hormone (GnRH) peptide family has dual roles in endocrine control of reproduction and energy status in fish. Atlantic cod (Gadus morhua) are a commercially important aquaculture species inhabiting the shores of Atlantic Canada. In this study, we examine MCH and GnRH transcript expression profiles during early development as well as in central and peripheral tissues and quantify juvenile Atlantic cod MCH and GnRH hypothalamic mRNA expressions following food deprivation. MCH and GnRH3 cDNAs are maternally deposited into cod eggs, while MCH has variable expression throughout early development. GnRH2 and GnRH3 mRNAs "turn-on" during mid-segmentation once the brain is fully developed. For both MCH and GnRH, highest expression appears during the exogenous feeding stages, perhaps supporting their functions as appetite regulators during early development. MCH and GnRH transcripts are found in brain regions related to appetite regulation (telencephalon/preoptic area, optic tectum/thalamus, hypothalamus), as well as the pituitary gland and the stomach, suggesting a peripheral function in food intake regulation. Atlantic cod MCH mRNA is upregulated during fasting, while GnRH2 and GnRH3 transcripts do not appear to be influenced by food deprivation. In conclusion, MCH might be involved in stimulating food intake in juvenile Atlantic cod, while GnRHs may play a more significant role in appetite regulation during early development.

  16. Four gonadotropin releasing hormone receptor genes in Atlantic cod are differentially expressed in the brain and pituitary during puberty.

    PubMed

    Hildahl, Jon; Sandvik, Guro K; Edvardsen, Rolf B; Norberg, Birgitta; Haug, Trude M; Weltzien, Finn-Arne

    2011-09-01

    Gonadotropin releasing hormones (GnRH) are an important part of the brain-pituitary-gonad axis in vertebrates. GnRH binding to its receptors (GnRH-R) stimulates synthesis and release of gonadotropins in the pituitary. GnRH-Rs also mediate other processes in the central nervous system such as reproductive behavior and neuromodulation. As many as five GnRH-R genes have been identified in two teleost fish species, but the function and phylogenetic relationship of these receptors is not fully understood. To gain a better understanding of the functional relationship between multiple GnRH-Rs in an important aquaculture species, the Atlantic cod (Gadus morhua), we identified four GnRH-Rs (gmGnRH-R) by RT-PCR, followed by full-length cloning and sequencing. The deduced amino acid sequences were used for phylogenetic analysis to identify conserved functional motifs and to clarify the relationship of gmGnRH-Rs with other vertebrate GnRH-Rs. The function of GnRH-R variants was investigated by quantitative PCR gene expression analysis in the brain and pituitary of female cod during a full reproductive cycle and in various peripheral tissues in sexually mature fish. Phylogenetic analysis revealed two types of teleost GnRH-Rs: Type I including gmGnRH-R1b and Type II including gmGnRH-R2a, gmGnRH-R2b and gmGnRH-R2c. All four gmGnRH-Rs are expressed in the brain, and gmGnRH-R1b, gmGnRH-R2a and gmGnRH-R2c are expressed in the pituitary. The only GnRH-R differentially expressed in the pituitary during the reproductive cycle is gmGnRH-R2a such that its expression is significantly increased during spawning. These data suggest that gmGnRH-R2a is the most likely candidate to mediate the hypophysiotropic function of GnRH in Atlantic cod.

  17. Synergies between climate and management for Atlantic cod fisheries at high latitudes

    PubMed Central

    Kjesbu, Olav Sigurd; Bogstad, Bjarte; Devine, Jennifer A.; Gjøsæter, Harald; Howell, Daniel; Ingvaldsen, Randi B.; Nash, Richard D. M.; Skjæraasen, Jon Egil

    2014-01-01

    The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and positive changes in population size, this invariably leads to questions about whether favorable climatic conditions or good management (or both) were responsible. The Barents Sea cod (Gadus morhua) stock has recently increased markedly and the spawning stock biomass is now at an unprecedented high. We identify the crucial social and environmental factors that made this unique growth possible. The relationship between vital rates of Barents Sea cod stock productivity (recruitment, growth, and mortality) and environment is investigated, followed by simulations of population size under different management scenarios. We show that the recent sustained reduction in fishing mortality, facilitated by the implementation of a “harvest control rule,” was essential to the increase in population size. Simulations show that a drastic reduction in fishing mortality has resulted in a doubling of the total population biomass compared with that expected under the former management regime. However, management alone was not solely responsible. We document that prevailing climate, operating through several mechanistic links, positively reinforced management actions. Heightened temperature resulted in an increase in the extent of the suitable feeding area for Barents Sea cod, likely offering a release from density-dependent effects (for example, food competition and cannibalism) through prolonged overlap with prey and improved adult stock productivity. Management and climate may thus interact to give a positive outlook for exploited high-latitude marine resources. PMID:24550465

  18. Genetic and morphological variation in Echinorhynchus gadi Zoega in Müller, 1776 (Acanthocephala: Echinorhynchidae) from Atlantic cod Gadus morhua L.

    PubMed

    Sobecka, E; Szostakowska, B; MacKenzie, K; Hemmingsen, W; Prajsnar, S; Eydal, M

    2012-03-01

    Previous studies have shown considerable variability in morphological features and the existence of genetically distinct sibling species in the acanthocephalan Echinorhynchus gadi Zoega in Müller, 1776. The aim of the present study was to follow up and extend those earlier studies by using a combination of DNA analysis and morphometrics to investigate differences between samples of E. gadi from Atlantic cod Gadus morhua L. caught at five fishing grounds in the Baltic Sea and three in different parts of the North Atlantic. Twelve morphological features were measured in 431 specimens of E. gadi, 99 individuals were studied by polymerase chain reaction-restriction fragment length polymorphosm (PCR-RFLP), and selected PCR products were sequenced. The molecular analyses showed the nucleotide sequences of E. gadi rDNA from cod caught at all the sampling sites to be identical. The comparative morphological study, in contrast, revealed significant differences between samples of E. gadi from different sampling sites and showed the separation of E. gadi into two groups corresponding approximately to the systematic classification of cod into the two subspecies, Atlantic G. morhua morhua and Baltic G. morhua callarias. The E. gadi infrapopulation size had a significant effect on some of the morphological features. The results are discussed in relation to cod population biology, the hydrography of the study area and the history of the Baltic Sea formation.

  19. Nitrogen excretion and expression of urea cycle enzymes in the atlantic cod (Gadus morhua l.): a comparison of early life stages with adults

    PubMed

    Chadwick; Wright

    1999-10-01

    For many years, the urea cycle was considered to be relatively unimportant in the life history of most teleost fishes. In previous studies, we were surprised to find that newly hatched freshwater rainbow trout embryos had relatively high activities of the key urea cycle enzyme, carbamoyl phosphate synthetase III (CPSase III), and other enzymes in the pathway, whereas adult trout had much lower or non-detectable activities. The present study tested the hypothesis that urea cycle enzyme expression is unique to early stages of rainbow trout. In marine Atlantic cod (Gadus morhua) embryos, CPSase III, ornithine transcarbamoylase (OTCase), glutamine synthetase (GSase) and arginase activities were all expressed prior to hatching. Urea excretion was detected shortly after fertilization and rates were high relative to those of ammonia excretion (50-100 % of total nitrogen excreted as urea nitrogen; total=ammonia+urea). Urea concentration was relatively constant in embryos, but ammonia concentration increased by about fourfold during embryogenesis. Two populations of cod embryos were studied (from Newfoundland and New Brunswick), and significant differences in enzyme activities and excretion rates were detected between the two populations. In adult cod, CPSase III was not detectable in liver, white muscle, intestine and kidney tissues, but OTCase, GSase and arginase were present. Adult cod excreted about 17 % of nitrogenous waste as urea. Taken together, these data indicate that early urea cycle enzyme expression is not unique to rainbow trout but is also a feature of Atlantic cod development, and possibly other teleosts. The relatively high urea excretion rates underline the importance of urea as the primary nitrogen excretory product in Atlantic cod during early embryogenesis.

  20. Precision-cut liver slices of Atlantic cod (Gadus morhua): an in vitro system for studying the effects of environmental contaminants.

    PubMed

    Eide, M; Karlsen, O A; Kryvi, H; Olsvik, P A; Goksøyr, A

    2014-08-01

    The Atlantic cod (Gadus morhua) is an economically important species commonly consumed by humans. The widespread distribution of cod in the North Atlantic Ocean makes it vulnerable to effluents from human activities, such as coastal industries and offshore petroleum exploration. It has been demonstrated that many effluents have adverse effects on cod reproduction and health, e.g. by disrupting endocrine signaling pathways. The liver, expressing important components of the biotransformation and the endocrine system, is one of the main target organs. Thus, reliable and reproducible in vitro systems of the liver are important for studying effects of environmental contaminants. The aim of this study was to investigate precision-cut liver slices (PCLS) as an alternative in vitro system for toxicological studies of the Atlantic cod liver. Slices of 8 mm in diameter and 250 μm thickness were prepared and cultivated from immature cod. Several analyses to measure the liver slice viability were performed: enzyme assays, histology, and morphometric analysis, all confirming cell viability for up to 72 h in culture. The liver slices were also exposed to two well-known model environmental contaminants, β-naphthoflavone (BNF) and 17α-ethynylestradiol (EE2), representing established agonists for the aryl hydrocarbon receptor (AHR) and the estrogen receptor (ER), respectively. The results showed increased transcription of the target genes cytochrome P450 1A (CYP1A) and vitellogenin (VTG), both well-established biomarkers for exposure of fish to the selected compounds. In conclusion, PCLS is a promising in vitro system for toxicological studies of cod liver cells. The liver slices are viable in culture for several days and respond to environmental contaminants in a dose- and time-specific manner.

  1. Correlation between microbiota and growth in Mangrove Killifish (Kryptolebias marmoratus) and Atlantic cod (Gadus morhua)

    PubMed Central

    Forberg, Torunn; Sjulstad, Eli Bjørnø; Bakke, Ingrid; Olsen, Yngvar; Hagiwara, Atsushi; Sakakura, Yoshitaka; Vadstein, Olav

    2016-01-01

    The vertebrate gut is host to large communities of bacteria, and one of the beneficial contributions of this commensal gut microbiota is the increased nutritional gain from feed components that the host cannot degrade on its own. Fish larvae of similar age and under the same rearing conditions often diverge with regards to growth. The underlying reasons for this could be differences in genetic background, feeding behavior or digestive capacity. Both feeding behavior and digestion can be influenced by differences in the microbiota. To investigate possible correlations between the size of fish larvae and their gut microbiota, we analyzed the microbiota small and large genetically homogenous killifish and genetically heterogeneous cod larvae by Bray-Curtis Similarity measures of 16S DNA DGGE patterns. A significant difference in richness (p = 0.037) was observed in the gut microbiota of small and large killifish, but the overall gut microbiota was not found to be significantly different (p = 0.13), indicating strong genetic host selection on microbiota composition at the time of sampling. The microbiota of small and large cod larvae was significantly different with regards to evenness and diversity (p = 0.0001), and a strong correlation between microbiota and growth was observed. PMID:26875510

  2. Correlation between microbiota and growth in Mangrove Killifish (Kryptolebias marmoratus) and Atlantic cod (Gadus morhua).

    PubMed

    Forberg, Torunn; Sjulstad, Eli Bjørnø; Bakke, Ingrid; Olsen, Yngvar; Hagiwara, Atsushi; Sakakura, Yoshitaka; Vadstein, Olav

    2016-02-15

    The vertebrate gut is host to large communities of bacteria, and one of the beneficial contributions of this commensal gut microbiota is the increased nutritional gain from feed components that the host cannot degrade on its own. Fish larvae of similar age and under the same rearing conditions often diverge with regards to growth. The underlying reasons for this could be differences in genetic background, feeding behavior or digestive capacity. Both feeding behavior and digestion can be influenced by differences in the microbiota. To investigate possible correlations between the size of fish larvae and their gut microbiota, we analyzed the microbiota small and large genetically homogenous killifish and genetically heterogeneous cod larvae by Bray-Curtis Similarity measures of 16S DNA DGGE patterns. A significant difference in richness (p = 0.037) was observed in the gut microbiota of small and large killifish, but the overall gut microbiota was not found to be significantly different (p = 0.13), indicating strong genetic host selection on microbiota composition at the time of sampling. The microbiota of small and large cod larvae was significantly different with regards to evenness and diversity (p = 0.0001), and a strong correlation between microbiota and growth was observed.

  3. Large scale distribution of dioxins, PCBs, heavy metals, PAH-metabolites and radionuclides in cod (Gadus morhua) from the North Atlantic and its adjacent seas.

    PubMed

    Karl, Horst; Kammann, Ulrike; Aust, Marc-Oliver; Manthey-Karl, Monika; Lüth, Anja; Kanisch, Günter

    2016-04-01

    Regarding cod as sea food for human consumption and as bio indicator of the marine eco system, this study is the first approach to combine the analysis of organic and inorganic contaminants and radionuclides in cod muscle as well as PCDD/Fs and dl-PCBs in its livers from the same fishing areas. Concentrations of 1-hydroxypyrene, PCDD/Fs, PCBs, cesium-137 (Cs-137), cadmium and lead were determined in individual or pooled samples over a wide geographic area, including Greenland Seas, Barents Sea, North and Baltic Sea. Highest concentrations were found in samples from the Baltic Sea, lowest in the pristine areas of the Barents Sea and Greenland. Levels of contaminants in cod muscle were found to be far below the established EU maximum levels (ML), regardless of which fishing grounds. In contrast to this, most cod liver samples from the North and Baltic Sea showed PCDD/F and PCB contents exceeding the ML. In addition, new background assessment criteria (BAC) for 1-hydroxypyrene in cod of 4.6 ng mL(-1) bile and for Cs-137 a BAC of 0.16 Bq kg(-1) wet weight are proposed to be included in the European Marine Strategy Framework Directive for cod from the Northeast Atlantic.

  4. Changes in natural mortality of Atlantic cod ( Gadus morhua) on Eastern Georges Bank

    NASA Astrophysics Data System (ADS)

    Wang, Yanjun

    2016-10-01

    The assessment of Eastern Georges Bank cod with the assumption of a constant natural mortality of 0.2 has over-estimated stock productivity, resulting in a severe retrospective pattern since the late 2000s. Comparing relative exploitation rate (ratio of fishery catch at age to survey abundance indices at age) with total mortality calculated from the age distribution in surveys indicated a conflict when constant natural mortality was assumed. This inconsistency implies an increase in natural mortality since the mid-1990s. In this paper, natural mortality estimated by Virtual Population Analysis (VPA) indicated that natural mortality for this stock has increased to 0.8 since the mid-1990s for ages 6+. Potential factors contributing to this elevated natural mortality, including poor fish conditions and increased losses due to seal predation were discussed.

  5. Ocean warming and acidification modulate energy budget and gill ion regulatory mechanisms in Atlantic cod (Gadus morhua).

    PubMed

    Kreiss, C M; Michael, K; Lucassen, M; Jutfelt, F; Motyka, R; Dupont, S; Pörtner, H-O

    2015-10-01

    Ocean warming and acidification are threatening marine ecosystems. In marine animals, acidification is thought to enhance ion regulatory costs and thereby baseline energy demand, while elevated temperature also increases baseline metabolic rate. Here we investigated standard metabolic rates (SMR) and plasma parameters of Atlantic cod (Gadus morhua) after 3-4 weeks of exposure to ambient and future PCO2 levels (550, 1200 and 2200 µatm) and at two temperatures (10, 18 °C). In vivo branchial ion regulatory costs were studied in isolated, perfused gill preparations. Animals reared at 18 °C responded to increasing CO2 by elevating SMR, in contrast to specimens at 10 °C. Isolated gills at 10 °C and elevated PCO2 (≥1200 µatm) displayed increased soft tissue mass, in parallel to increased gill oxygen demand, indicating an increased fraction of gill in whole animal energy budget. Altered gill size was not found at 18 °C, where a shift in the use of ion regulation mechanisms occurred towards enhanced Na(+)/H(+)-exchange and HCO3 (-) transport at high PCO2 (2200 µatm), paralleled by higher Na(+)/K(+)-ATPase activities. This shift did not affect total gill energy consumption leaving whole animal energy budget unaffected. Higher Na(+)/K(+)-ATPase activities in the warmth might have compensated for enhanced branchial permeability and led to reduced plasma Na(+) and/or Cl(-) concentrations and slightly lowered osmolalities seen at 18 °C and 550 or 2200 µatm PCO2 in vivo. Overall, the gill as a key ion regulation organ seems to be highly effective in supporting the resilience of cod to effects of ocean warming and acidification.

  6. Characterisation and expression of secretory phospholipase A2 group IB during ontogeny of Atlantic cod ( Gadus morhua).

    PubMed

    Sæle, Øystein; Nordgreen, Andreas; Olsvik, Pål A; Hamre, Kristin

    2011-01-01

    The pancreatic enzyme secretory phospholipase A2 group IB (sPLA2 IB) hydrolyses phospholipids at the sn-2 position, resulting in a NEFA and a lyso-phospholipid, which are then absorbed by the enterocytes. The sPLA2 IB is a member of a family of nineteen enzymes sharing the same catalytic ability, of which nine are cytosolic and ten are secretory. Presently, there are no pharmacological tools to separate between the different secretory enzymes when measuring the enzymatic activity. Thus, it is important to support activity data with more precise techniques when isolation of intestinal content is not possible for analysis, as in the case of small teleost larvae, where the whole animal is sometimes analysed. In the present study, we characterise the sPLA2 IB gene in Atlantic cod (Gadus morhua) and describe its ontogeny at the genetic and protein level and compare this to the total sPLA2 activity level. A positive correlation was found between the expression of sPLA2 IB mRNA and protein. Both remained stable and low during the larval stage followed by an increase from day 62 posthatch, coinciding with the development of the pyloric ceaca. Meanwhile, total sPLA2 enzyme activity in cod was stable and relatively high during the early stages when larvae were fed live prey, followed by a decrease in activity when the fish were weaned to a formulated diet. Thus, the expression of sPLA2 IB mRNA and protein did not correlate with total sPLA2 activity.

  7. Life on the edge: O2 binding in Atlantic cod red blood cells near their southern distribution limit is not sensitive to temperature or haemoglobin genotype.

    PubMed

    Barlow, Samantha L; Metcalfe, Julian; Righton, David A; Berenbrink, Michael

    2017-02-01

    Atlantic cod are a commercially important species believed to be threatened by warming seas near their southern, equatorward upper thermal edge of distribution. Limitations to circulatory O2 transport, in particular cardiac output, and the geographic distribution of functionally different haemoglobin (Hb) genotypes have separately been suggested to play a role in setting thermal tolerance in this species. The present study assessed the thermal sensitivity of O2 binding in Atlantic cod red blood cells with different Hb genotypes near their upper thermal distribution limit and modelled its consequences for the arterio-venous O2 saturation difference, Sa-vO2 , another major determinant of circulatory O2 supply rate. The results showed statistically indistinguishable red blood cell O2 binding between the three HbI genotypes in wild-caught Atlantic cod from the Irish Sea (53° N). Red blood cells had an unusually low O2 affinity, with reduced or even reversed thermal sensitivity between pH 7.4 and 7.9, and 5.0 and 20.0°C. This was paired with strongly pH-dependent affinity and cooperativity of red blood cell O2 binding (Bohr and Root effects). Modelling of Sa-vO2  at physiological pH, temperature and O2 partial pressures revealed a substantial capacity for increases in Sa-vO2  to meet rising tissue O2 demands at 5.0 and 12.5°C, but not at 20°C. Furthermore, there was no evidence for an increase of maximal Sa-vO2  with temperature. It is suggested that Atlantic cod at such high temperatures may solely depend on increases in cardiac output and blood O2 capacity, or thermal acclimatisation of metabolic rate, for matching circulatory O2 supply to tissue demand.

  8. Life on the edge: O2 binding in Atlantic cod red blood cells near their southern distribution limit is not sensitive to temperature or haemoglobin genotype

    PubMed Central

    Barlow, Samantha L.; Metcalfe, Julian; Righton, David A.

    2017-01-01

    ABSTRACT Atlantic cod are a commercially important species believed to be threatened by warming seas near their southern, equatorward upper thermal edge of distribution. Limitations to circulatory O2 transport, in particular cardiac output, and the geographic distribution of functionally different haemoglobin (Hb) genotypes have separately been suggested to play a role in setting thermal tolerance in this species. The present study assessed the thermal sensitivity of O2 binding in Atlantic cod red blood cells with different Hb genotypes near their upper thermal distribution limit and modelled its consequences for the arterio-venous O2 saturation difference, Sa–vO2, another major determinant of circulatory O2 supply rate. The results showed statistically indistinguishable red blood cell O2 binding between the three HbI genotypes in wild-caught Atlantic cod from the Irish Sea (53° N). Red blood cells had an unusually low O2 affinity, with reduced or even reversed thermal sensitivity between pH 7.4 and 7.9, and 5.0 and 20.0°C. This was paired with strongly pH-dependent affinity and cooperativity of red blood cell O2 binding (Bohr and Root effects). Modelling of Sa–vO2 at physiological pH, temperature and O2 partial pressures revealed a substantial capacity for increases in Sa–vO2 to meet rising tissue O2 demands at 5.0 and 12.5°C, but not at 20°C. Furthermore, there was no evidence for an increase of maximal Sa–vO2 with temperature. It is suggested that Atlantic cod at such high temperatures may solely depend on increases in cardiac output and blood O2 capacity, or thermal acclimatisation of metabolic rate, for matching circulatory O2 supply to tissue demand. PMID:28148818

  9. Impacts of regular and random noise on the behaviour, growth and development of larval Atlantic cod (Gadus morhua)

    PubMed Central

    Nedelec, Sophie L.; Simpson, Stephen D.; Morley, Erica L.; Nedelec, Brendan; Radford, Andrew N.

    2015-01-01

    Anthropogenic noise impacts behaviour and physiology in many species, but responses could change with repeat exposures. As repeat exposures can vary in regularity, identifying regimes with less impact is important for regulation. We use a 16-day split-brood experiment to compare effects of regular and random acoustic noise (playbacks of recordings of ships), relative to ambient-noise controls, on behaviour, growth and development of larval Atlantic cod (Gadus morhua). Short-term noise caused startle responses in newly hatched fish, irrespective of rearing noise. Two days of both regular and random noise regimes reduced growth, while regular noise led to faster yolk sac use. After 16 days, growth in all three sound treatments converged, although fish exposed to regular noise had lower body width–length ratios. Larvae with lower body width–length ratios were easier to catch in a predator-avoidance experiment. Our results demonstrate that the timing of acoustic disturbances can impact survival-related measures during development. Much current work focuses on sound levels, but future studies should consider the role of noise regularity and its importance for noise management and mitigation measures. PMID:26468248

  10. Characterization of Francisella sp., GM2212, the first Francisella isolate from marine fish, Atlantic cod (Gadus morhua).

    PubMed

    Ottem, Karl F; Nylund, Are; Karlsbakk, Egil; Friis-Møller, Alice; Krossøy, Bjørn

    2007-05-01

    A Francisella sp., isolate GM2212(T), previously isolated from diseased farmed Atlantic cod Gadus morhua in Norway is characterized. The complete 16S rDNA, 16S-23S intergenic spacer, 23S rDNA, 23S-5S intergenic spacer, 5S rDNA, FopA, lipoprotein TUL4 (LpnA), malate dehydrogenase and a hypothetical lipoprotein (LpnB) is sequenced and compared with Francisella tularensis and Francisella philomiragia. All these sequences support a close relationship between GM2212(T) and F. philomiragia. The bacterium grows at 10-25 degrees C with an optimum at about 20 degrees C, a temperature range clearly different from F. tularensis and F. philomiragia. GM2212(T) is catalase-positive, indole positive, oxidase-negative, do not produce H(2)S in Triple Sugar Iron agar, and does not hydrolyze gelatin, is resistant to erythromycin and susceptible to ceftazidime, the latter five characteristics separating it from F. philomiragia. Cysteine enhances growth. Acid is produced from D: -glucose, maltose, sucrose (weak) but not from lactose or glycerol. GM2212(T) grows on both MacConkey agar and in nutrient broth (6% NaCl). The bacterium is resistant to trimethoprim-sulfamethoxazole, penicillines, cefuroxime and erythromycin; but is susceptible to ceftazidime, tetracycline, gentamicin, ciprofloxacin. Based on the molecular and phenotypical characteristics, we suggest that this GM2212 isolate, may represent a new species of Francisella. Isolate GM2212(T) (=CNCM I-3481(T) = CNCM I-3511(T) = DSM 18777(T)).

  11. Impacts of regular and random noise on the behaviour, growth and development of larval Atlantic cod (Gadus morhua).

    PubMed

    Nedelec, Sophie L; Simpson, Stephen D; Morley, Erica L; Nedelec, Brendan; Radford, Andrew N

    2015-10-22

    Anthropogenic noise impacts behaviour and physiology in many species, but responses could change with repeat exposures. As repeat exposures can vary in regularity, identifying regimes with less impact is important for regulation. We use a 16-day split-brood experiment to compare effects of regular and random acoustic noise (playbacks of recordings of ships), relative to ambient-noise controls, on behaviour, growth and development of larval Atlantic cod (Gadus morhua). Short-term noise caused startle responses in newly hatched fish, irrespective of rearing noise. Two days of both regular and random noise regimes reduced growth, while regular noise led to faster yolk sac use. After 16 days, growth in all three sound treatments converged, although fish exposed to regular noise had lower body width-length ratios. Larvae with lower body width-length ratios were easier to catch in a predator-avoidance experiment. Our results demonstrate that the timing of acoustic disturbances can impact survival-related measures during development. Much current work focuses on sound levels, but future studies should consider the role of noise regularity and its importance for noise management and mitigation measures. © 2015 The Authors.

  12. Statistical analysis of North Atlantic right whale (Eubalaena glacialis) signal trains in Cape Cod Bay, spring 2012.

    PubMed

    Urazghildiiev, Ildar R

    2014-11-01

    Statistical characteristics of signal trains produced by North Atlantic right whales (NARW) during the winter and early spring in Cape Cod Bay, MA are described. Data analysis was based on four days of acoustic recordings that were obtained with synchronized hydrophones. Based on temporal and geographical clustering of detected signals, 7264 NARW sounds were identified and associated with 559 signal trains. The detected signals were assigned to four classes of narrowband tonal calls--upcalls, downcalls, complex, and high frequency, and two classes of wideband sounds--gunshots and complex. Empirical distributions of the number of signals in trains, total duration of trains, the positions of NARW, and signal classes are presented. Results indicate that 68.9% of all signal trains consisted of 10 or fewer signals. Low and high frequency tonals that lacked wideband sounds formed 69.1% of trains; 5.0% of trains lacked tonals. Trains consisting of only upcalls comprised 44.2% of all detected trains. Because 18.3% of trains contained no upcalls, using detectors that identify all signal classes would improve right whale detection.

  13. Harvest Pressure on Coastal Atlantic Cod (Gadus morhua) from Recreational Fishing Relative to Commercial Fishing Assessed from Tag-Recovery Data

    PubMed Central

    Kleiven, Alf Ring; Fernandez-Chacon, Albert; Nordahl, Jan-Harald; Moland, Even; Espeland, Sigurd Heiberg; Knutsen, Halvor; Olsen, Esben Moland

    2016-01-01

    Marine recreational fishing is a popular outdoor activity. However, knowledge about the magnitude of recreational catches relative to commercial catches in coastal fisheries is generally sparse. Coastal Atlantic cod (Gadus morhua) is a target species for recreational fishers in the North Atlantic. In Norway, recreational fishers are allowed to use a variety of traps and nets as well as long-line and rod and line when fishing for cod. From 2005 to 2013, 9729 cod (mean size: 40 cm, range: 15–93 cm) were tagged and released in coastal Skagerrak, southeast Norway. Both high-reward (NOK 500) and low-reward tags (NOK 50) were used in this study. Because some harvested fish (even those posting high-reward tags) may go unreported by fishers, reporting rates were estimated from mark-recovery models that incorporate detection parameters in their structure, in addition to survival and mortality estimates. During 2005 to 2013, a total of 1707 tagged cod were recovered and reported by fishers. We estimate the overall annual survival to be 33% (SE 1.5). Recreational rod and line fishing were responsible for 33.7% (SE 2.4) of total mortality, followed by commercial fisheries (15.1% SE 0.8) and recreational fixed gear (6.8% SE 0.4). Natural mortality was 44.4% (SE 2.5) of total mortality. Our findings suggest that recreational fishing—rod and line fishing in particular—is responsible for a substantial part of fishing mortality exerted on coastal cod in southern Norway. PMID:26959371

  14. The mRNA expression of cortisol axis related genes differs in Atlantic cod (Gadus morhua) categorized as high or low responders.

    PubMed

    Hori, Tiago S; Rise, Matthew L; Johnson, Stewart C; Afonso, Luis O B; Gamperl, A Kurt

    2012-01-15

    Cortisol is a major stress hormone in fish and is known, under normal or stressful conditions, to affect several physiological processes including growth and immunity. Thus, efforts have been made for several cultured finfish species, including the Atlantic cod, to determine whether fish with a high or low cortisol response to stress can be identified and selected. However, we have a limited understanding of the mechanisms that determine these two phenotypes. Thus, we measured total and free plasma cortisol levels in high and low responding cod when subjected to a 30 s handling stress, and the mRNA expression of four key genes in the glucocorticoid (i.e. cortisol) stress axis both pre- and post-stress. The cortisol data is consistent with our previous findings for cod, with high responding (HR) fish having ∼3-fold higher total and free plasma cortisol levels when compared to low responding (LR) fish. Three of the transcripts studied encode key proteins involved in steroidogenesis (StAR, P450scc and 3βHSD), and the constitutive mRNA expression of all three genes was significantly higher (∼2-fold) in the head kidney of HR fish when compared to LR cod. The other gene of interest was the glucocorticoid receptor (GR). We partly cloned and characterized a cDNA from Atlantic cod likely to be this fish's ortholog of the teleost GR1, and showed that while there was no difference in hepatic constitutive GR mRNA expression between groups, HR fish had liver GR mRNA levels that were significantly (1.8-fold) higher at 3 h post-stress as compared to LR fish. Our results suggest that the different magnitude of cortisol response between LR and HR fish is at least partially determined by the capacity of the interrenal tissue to produce steroids.

  15. Harvest Pressure on Coastal Atlantic Cod (Gadus morhua) from Recreational Fishing Relative to Commercial Fishing Assessed from Tag-Recovery Data.

    PubMed

    Kleiven, Alf Ring; Fernandez-Chacon, Albert; Nordahl, Jan-Harald; Moland, Even; Espeland, Sigurd Heiberg; Knutsen, Halvor; Olsen, Esben Moland

    2016-01-01

    Marine recreational fishing is a popular outdoor activity. However, knowledge about the magnitude of recreational catches relative to commercial catches in coastal fisheries is generally sparse. Coastal Atlantic cod (Gadus morhua) is a target species for recreational fishers in the North Atlantic. In Norway, recreational fishers are allowed to use a variety of traps and nets as well as long-line and rod and line when fishing for cod. From 2005 to 2013, 9729 cod (mean size: 40 cm, range: 15-93 cm) were tagged and released in coastal Skagerrak, southeast Norway. Both high-reward (NOK 500) and low-reward tags (NOK 50) were used in this study. Because some harvested fish (even those posting high-reward tags) may go unreported by fishers, reporting rates were estimated from mark-recovery models that incorporate detection parameters in their structure, in addition to survival and mortality estimates. During 2005 to 2013, a total of 1707 tagged cod were recovered and reported by fishers. We estimate the overall annual survival to be 33% (SE 1.5). Recreational rod and line fishing were responsible for 33.7% (SE 2.4) of total mortality, followed by commercial fisheries (15.1% SE 0.8) and recreational fixed gear (6.8% SE 0.4). Natural mortality was 44.4% (SE 2.5) of total mortality. Our findings suggest that recreational fishing-rod and line fishing in particular-is responsible for a substantial part of fishing mortality exerted on coastal cod in southern Norway.

  16. Evidence of microsatellite hitch-hiking selection in Atlantic cod (Gadus morhua L.): implications for inferring population structure in nonmodel organisms.

    PubMed

    Nielsen, Einar E; Hansen, Michael M; Meldrup, Dorte

    2006-10-01

    Microsatellites have gained wide application for elucidating population structure in nonmodel organisms. Since they are generally noncoding, neutrality is assumed but rarely tested. In Atlantic cod (Gadus morhua L.), microsatellite studies have revealed highly heterogeneous estimates of genetic differentiation among loci. In particular one locus, Gmo 132, has demonstrated elevated genetic differentiation. We investigated possible hitch-hiking selection at this and other microsatellite loci in Atlantic cod. We employed 11 loci for analysing samples from the Baltic Sea, North Sea, Barents Sea and Newfoundland covering a large part of the species' distributional range. The 'classical' Lewontin-Krakauer test for selection based on variance in estimates of F(ST) and (standardized genetic differentiation) revealed only one significant pairwise test (North Sea-Barents Sea), and the source of the elevated variance could not be ascribed exclusively to Gmo 132. In contrast, different variants of the recently developed ln Rtheta test for selective sweeps at microsatellite loci revealed a high number of significant outcomes of pair-wise tests for Gmo 132. Further, the presence of selection was indicated in at least one other locus. The results suggest that many previous estimates of genetic differentiation in cod based on microsatellites are inflated, and in some cases relationships among populations are obscured by one or more loci being the subject to hitch-hiking selection. Likewise, temporal estimates of effective population sizes in Atlantic cod may be flawed. We recommend, generally, to use a higher number of microsatellite loci to elucidate population structure in marine fishes and other nonmodel species to allow for identification of outlier loci that are subject to selection.

  17. Discrimination between Weaned and Unweaned Atlantic Cod (Gadus morhua) in Capture-Based Aquaculture (CBA) by X-Ray Imaging and Radio-Frequency Metal Detector

    PubMed Central

    Misimi, Ekrem; Martinsen, Svein; Mathiassen, John Reidar; Erikson, Ulf

    2014-01-01

    The aim of this study was to investigate the feasibility of two detection methods for use in discrimination and sorting of adult Atlantic cod (about 2 kg) in the small scale capture-based aquaculture (CBA). Presently, there is no established method for discrimination of weaned and unweaned cod in CBA. Generally, 60–70% of the wild-caught cod in the CBA are weaned into commercial dry feed. To increase profitability for the fish farmers, unweaned cod must be separated from the stock, meaning the fish must be sorted into two groups – unweaned and weaned from moist feed. The challenges with handling of large numbers of fish in cages, defined the limits of the applied technology. As a result, a working model was established, focusing on implementing different marking materials added to the fish feed, and different technology for detecting the feed presence in the fish gut. X-ray imaging in two modes (planar and dual energy band) and sensitive radio-frequency metal detection were the detection methods that were chosen for the investigations. Both methods were tested in laboratory conditions using dead fish with marked feed inserted into the gut cavity. In particular, the sensitive radio-frequency metal detection method with carbonyl powder showed very promising results in detection of marked feed. Results show also that Dual energy band X-ray imaging may have potential for prediction of fat content in the feed. Based on the investigations it can be concluded that both X-ray imaging and sensitive radio-frequency metal detector technology have the potential for detecting cod having consumed marked feed. These are all technologies that may be adapted to large scale handling of fish from fish cages. Thus, it may be possible to discriminate between unweaned and weaned cod in a large scale grading situation. Based on the results of this study, a suggestion for evaluation of concept for in-situ sorting system is presented. PMID:24743448

  18. Discrimination between weaned and unweaned Atlantic cod (Gadus morhua) in capture-based aquaculture (CBA) by X-ray imaging and radio-frequency metal detector.

    PubMed

    Misimi, Ekrem; Martinsen, Svein; Mathiassen, John Reidar; Erikson, Ulf

    2014-01-01

    The aim of this study was to investigate the feasibility of two detection methods for use in discrimination and sorting of adult Atlantic cod (about 2 kg) in the small scale capture-based aquaculture (CBA). Presently, there is no established method for discrimination of weaned and unweaned cod in CBA. Generally, 60-70% of the wild-caught cod in the CBA are weaned into commercial dry feed. To increase profitability for the fish farmers, unweaned cod must be separated from the stock, meaning the fish must be sorted into two groups - unweaned and weaned from moist feed. The challenges with handling of large numbers of fish in cages, defined the limits of the applied technology. As a result, a working model was established, focusing on implementing different marking materials added to the fish feed, and different technology for detecting the feed presence in the fish gut. X-ray imaging in two modes (planar and dual energy band) and sensitive radio-frequency metal detection were the detection methods that were chosen for the investigations. Both methods were tested in laboratory conditions using dead fish with marked feed inserted into the gut cavity. In particular, the sensitive radio-frequency metal detection method with carbonyl powder showed very promising results in detection of marked feed. Results show also that Dual energy band X-ray imaging may have potential for prediction of fat content in the feed. Based on the investigations it can be concluded that both X-ray imaging and sensitive radio-frequency metal detector technology have the potential for detecting cod having consumed marked feed. These are all technologies that may be adapted to large scale handling of fish from fish cages. Thus, it may be possible to discriminate between unweaned and weaned cod in a large scale grading situation. Based on the results of this study, a suggestion for evaluation of concept for in-situ sorting system is presented.

  19. Optimization and comparison of miniaturized extraction techniques for PAHs from crude oil exposed Atlantic cod and haddock eggs.

    PubMed

    Sørensen, Lisbet; Silva, Marta S; Booth, Andy M; Meier, Sonnich

    2016-02-01

    Two miniaturized extraction methods for a wide range of 2-6 ring polycyclic aromatic hydrocarbons (PAHs) and their alkylated homologues in small lipid-rich biota samples (≤100 mg) have been developed. Both methods utilize liquid extraction (LE) prior to a clean-up step using either normal phase solid phase extraction (SPE) or mixed-phase dispersive SPE (dSPE). Optimization of the methods was achieved by comparing the type and amount of sorbents, drying agents, and solvents used. In order to improve the limits of detection (LOD) of target PAHs under high sensitivity gas chromatography-tandem mass spectrometry analysis, specific emphasis was given to minimizing lipid co-extraction. The optimized LE-SPE method comprised extraction with dichloromethane/n-hexane (1:1, v/v) and clean-up by silica SPE, whereas the optimized LE-dSPE method comprised extraction with acetonitrile and clean-up with PSA and C18 sorbents. The methods were validated and directly compared through the analysis of Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) eggs exposed to oil. The LE-SPE method resulted in lower levels of co-extracted lipids (14.1 ± 1.7 ng/μL) than the LE-dSPE method (60 ± 14 ng/μL). Achieved PAH LODs for the LE-SPE method were typically an order of magnitude lower (<5 ng/g) than for the LE-dSPE method (<125 ng/g). The LE-SPE method offers the possibility for PAH analysis of small samples of fish eggs (~100 mg) exposed to small quantities of crude oil (~1-10 μg/L total PAHs).

  20. Global transcriptome analysis of Atlantic cod (Gadus morhua) liver after in vivo methylmercury exposure suggests effects on energy metabolism pathways.

    PubMed

    Yadetie, Fekadu; Karlsen, Odd Andre; Lanzén, Anders; Berg, Karin; Olsvik, Pål; Hogstrand, Christer; Goksøyr, Anders

    2013-01-15

    Methylmercury (MeHg) is a widely distributed contaminant polluting many aquatic environments, with health risks to humans exposed mainly through consumption of seafood. The mechanisms of toxicity of MeHg are not completely understood. In order to map the range of molecular targets and gain better insights into the mechanisms of toxicity, we prepared Atlantic cod (Gadus morhua) 135k oligonucleotide arrays and performed global analysis of transcriptional changes in the liver of fish treated with MeHg (0.5 and 2 mg/kg of body weight) for 14 days. Inferring from the observed transcriptional changes, the main pathways significantly affected by the treatment were energy metabolism, oxidative stress response, immune response and cytoskeleton remodeling. Consistent with known effects of MeHg, many transcripts for genes in oxidative stress pathways such as glutathione metabolism and Nrf2 regulation of oxidative stress response were differentially regulated. Among the differentially regulated genes, there were disproportionate numbers of genes coding for enzymes involved in metabolism of amino acids, fatty acids and glucose. In particular, many genes coding for enzymes of fatty acid beta-oxidation were up-regulated. The coordinated effects observed on many transcripts coding for enzymes of energy pathways may suggest disruption of nutrient metabolism by MeHg. Many transcripts for genes coding for enzymes in the synthetic pathways of sulphur containing amino acids were also up-regulated, suggesting adaptive responses to MeHg toxicity. By this toxicogenomics approach, we were also able to identify many potential biomarker candidate genes for monitoring environmental MeHg pollution. These results based on changes on transcript levels, however, need to be confirmed by other methods such as proteomics.

  1. Biological effects of polycyclic aromatic hydrocarbons (PAH) and their first metabolic products in in vivo exposed Atlantic cod (Gadus morhua).

    PubMed

    Pampanin, Daniela M; Le Goff, Jeremie; Skogland, Karianne; Marcucci, Cristian R; Øysæd, Kjell Birger; Lorentzen, Marianne; Jørgensen, Kåre B; Sydnes, Magne O

    2016-01-01

    The monitoring of the presence of polycyclic aromatic hydrocarbons (PAH) in the aquatic environment is a worldwide activity since some of these compounds are well-established carcinogens and mutagens. Contaminants in this class are in fact regarded as priority hazardous substances for environmental pollution (Water Framework Directive 2000/60/EC). In this study, Atlantic cod (Gadus morhua) was selected to assess in vivo effects of two PAH and their first metabolic products, namely, the corresponding trans-dihydrodiols, using biological markers. Fish were exposed for 1 wk to a single PAH (naphthalene or chrysene) and its synthetic metabolites ((1R,2R)-1,2-dihydronaphthalene-1,2-diol and (1R,2R)-1,2-dihydrochrysene-1,2-diol) by intraperitoneal injection in a continuous seawater flow system. After exposure, PAH metabolism including PAH metabolites in bile and ethoxyresorufin O-deethylase (EROD) activity, oxidative stress glutathione S-transferases (GST) and catalase (CAT) activities, and genotoxicity such as DNA adducts were evaluated, as well as general health conditions including condition index (CI), hepatosomatic index (HSI), and gonadosomatic index (GSI). PAH metabolite values were low and not significantly different when measured with the fixed-wavelength fluorescence screening method, while the gas chromatography-mass spectroscopy (GC-MS) method showed an apparent dose response in fish exposed to naphthalene. DNA adduct levels ≥0.16 × 10(-8) relative adduct level (RAL) were detected. It should be noted that 0.16 × 10(-8) RAL is considered the maximal acceptable background level for this species. The other biomarkers activities of catalase, GST, and EROD did not display a particular compound- or dose-related response. The GSI values were significantly lower in some chrysene- and in both naphthalene- and naphthalene diol-exposed groups compared to control.

  2. Effects of long-term temperature acclimation on thyroid hormone deiodinase function, plasma thyroid hormone levels, growth, and reproductive status of male Atlantic cod, Gadus morhua.

    PubMed

    Cyr, D G; Idler, D R; Audet, C; McLeese, J M; Eales, J G

    1998-01-01

    The recent collapse of the Northwestern Atlantic cod fisheries has coincided with a cooling of water temperatures. During this time the condition factor of cod has been poor. The objective of the present study was to determine the effects of long-term temperature acclimation on growth reproduction and thyroid function in laboratory held Atlantic cod (Gadus morhua). One of the key parameters used to assess thyroid function is the peripheral metabolism of L-thyroxine (T4) by microsomal deiodinase enzymes. Deiodinase function has not been described for gadid fish. T4 outer-ring deiodinating activity (apparent K(m) 1-2 nM) was confined primarily to liver. Its properties resembled those for hepatic T4ORD activity of other teleosts and the mammalian type II deiodinase. The T4ORD activity of cod liver exceeded that of salmonids and could explain the high plasma T3 levels (10-18 ng/ml), which were 2-5 times greater than T4 levels. T4 and T3 inner-ring deiodination was confined mainly to brain. In order to determine the effects of long-term temperature acclimation on cod, somatic growth, reproduction, and thyroidal status were assessed monthly in 400-900-g satiation-fed male Atlantic cod captured in June from the St. Lawrence Estuary and then acclimated from August to the following June under a natural photoperiod at 2-4 degrees C (LT) or 6-10 degrees C (HT). Reproductive status was determined from the gonadosomatic index (GSI), plasma testosterone (T) and 11-ketotestosterone (11-KT) levels, and the appearance of milt; thyroidal status was determined from plasma T4 and 3,5,3'-triiodo-L-thyronine (T3) levels and hepatic T4ORD activity to produce biologically active T3. Testis maturation (high levels of 1 and 11-KT, and milt release) occurred in April and May and was uninfluenced by acclimation temperature. LT cod grew more slowly than HT cod. Differences in body weight were particularly evident from December to February. In conclusion, (i) cod possess outer- and inner

  3. Differential regulation of GnRH ligand and receptor genes in the brain and pituitary of Atlantic cod exposed to different photoperiod.

    PubMed

    Hildahl, Jon; Taranger, Geir Lasse; Norberg, Birgitta; Haug, Trude M; Weltzien, Finn-Arne

    2013-01-01

    The onset of puberty and reproduction are tightly controlled by extrinsic and intrinsic inputs combined with genetically determined biological blueprints. Environmental inputs are then mediated by the brain-pituitary-gonad endocrine axis resulting in a unified output. In fish, one of the primary factors controlling the timing of sexual maturation is light, although how these signals are mediated in the brain and pituitary is not well understood. We therefore aimed to elucidate the molecular basis of the control of reproduction during the first spawning season in two year old female Atlantic cod. To this end, we measured GnRH and GnRH-R variant gene expression in brains and pituitaries collected from cod kept under four different photoperiod regimes: natural light (NL), continuous light (LL) and combined treatment of NL-LL and LL-NL. LL inhibited sexual development and spawning and LL-NL delayed sexual development and spawning. LL inhibited the spawning-related increase in brain GnRH3 and pituitary GnRH-R2a gene expression found under NL conditions, and the expression of these genes were delayed in concert with spawning of LL-NL cod. This study indicates that regulation of brain GnRH3 and pituitary GnRH-R2a genes likely mediates photoperiod induced changes in cod gonadal maturation.

  4. A review of the contributions of fisheries and climate variability to contrasting dynamics in two Arcto-boreal Atlantic cod (Gadus morhua) stocks: Persistent high productivity in the Barents Sea and collapse on the Newfoundland and Labrador Shelf

    NASA Astrophysics Data System (ADS)

    Lilly, George R.; Nakken, Odd; Brattey, John

    2013-07-01

    Stocks of Atlantic cod (Gadus morhua) across the North Atlantic and adjacent seas have been fished intensively for years, and many are now severely depleted. In order to promote recovery and sustainable harvesting, it is essential to understand factors that have contributed to the declines and to variability in rates of recovery. Considerable insight may be gleaned by comparing and contrasting the histories of the Northeast Arctic (NEA) cod in the Barents Sea - Svalbard area of the northeast Atlantic and the “northern cod” on the Newfoundland and Labrador (NL) shelf in the northwest Atlantic. These two stocks, which were among the 3 largest cod stocks during the middle of the 20th century, are Arcto-boreal, and have many species of prey and predators in common. The biomass of NEA cod has varied considerably over time, and in 2009 was a little above 60% of its maximum observed level, which occurred in the late 1940s and early 1950s. In contrast, the biomass of NL cod decreased steadily from the early 1960s to the late 1970s, increased somewhat during the 1980s, and crashed during the early 1990s to an extremely low level, at which it remained for a decade before showing recent indications of improvement. Although both stocks were influenced by similar changes in harvesting strategies and environmental circumstances, both biotic and abiotic, there are two events which stand out as being particularly influential. First, crises developed in the management of both stocks in the late 1980s. For NEA cod, the crisis was environmental, caused by the collapse of capelin (Mallotus villosus), the main food for adult cod, whereas for NL cod the crisis was caused by a sudden large reduction in scientific perception of stock size. The difference in response to these crises strongly influenced subsequent stock dynamics. Catches of NEA cod were reduced considerably, preventing severe overharvesting of the cod that at that time experienced low productivity, whereas catches of NL

  5. Low-dose exposure to alkylphenols adversely affects the sexual development of Atlantic cod (Gadus morhua): acceleration of the onset of puberty and delayed seasonal gonad development in mature female cod.

    PubMed

    Meier, Sonnich; Morton, H Craig; Andersson, Eva; Geffen, Audrey J; Taranger, Geir Lasse; Larsen, Marita; Petersen, Marianne; Djurhuus, Rune; Klungsøyr, Jarle; Svardal, Asbjørn

    2011-09-01

    Produced water (PW), a by-product of the oil-production process, contains large amount of alkylphenols (APs) and other harmful oil compounds. In the last 20 years, there have been increasing concerns regarding the environmental impact of large increases in the amounts of PW released into the North Sea. We have previously shown that low levels of APs can induce disruption of the endocrine and reproductive systems of Atlantic cod (Gadus morhua). The aims of this follow-up study were to: (i) identify the lowest observable effect concentration of APs; (ii) study the effects of exposure to real PW, obtained from a North Sea oil-production platform; and (iii) study the biological mechanism of endocrine disruption in female cod. Fish were fed with feed paste containing several concentrations of four different APs (4-tert-butylphenol, 4-n-pentylphenol, 4-n-hexylphenol and 4-n-heptylphenol) or real PW for 20 weeks throughout the normal period of vitellogenesis in Atlantic cod from October to January. Male and female cod, exposed to AP and PW, were compared to unexposed fish and to fish fed paste containing 17β-oestradiol (E(2)). Approximately 60% of the females and 96% of the males in the unexposed groups were mature at the end of the experiment. Our results show that exposure to APs and E(2) have different effects depending on the developmental stage of the fish. We observed that juvenile females are advanced into puberty and maturation, while gonad development was delayed in both maturing females and males. The AP-exposed groups contained increased numbers of mature females, and significant differences between the untreated group and the AP-treated groups were seen down to a dose of 4 μg AP/kg body weight. In the high-dose AP and the E(2) exposed groups, all females matured and no juveniles were seen. These results suggest that AP-exposure can affect the timing of the onset of puberty in fish even at extremely low concentrations. Importantly, similar effects were not

  6. Effect of replacement of fish oil with camelina (Camelina sativa) oil on growth, lipid class and fatty acid composition of farmed juvenile Atlantic cod (Gadus morhua).

    PubMed

    Hixson, Stefanie M; Parrish, Christopher C; Anderson, Derek M

    2013-12-01

    Camelina (Camelina sativa) oil was tested as a replacement for fish oil in diets for farmed Atlantic cod (Gadus morhua). Camelina differs from other plant oilseeds previously used in aquaculture with high lipid (40 %), α-linolenic acid (40 %), antioxidants and low proportions of saturated fats. Dietary treatments were fed to cod (19 g fish⁻¹ initial weight) for 9 weeks and included a fish oil control (FO), 40 % (CO40) and 80 % (CO80) replacement of fish oil with camelina oil. There was no effect of replacing fish oil with camelina oil included at levels up to 80 % on the growth performance. Cod fed CO80 stored more lipid in the liver (p < 0.01), including more neutral lipid (p < 0.05) and triacylglycerol (p < 0.05). Cod fed CO80 decreased in total polyunsaturated fatty acids (PUFAs) in muscle compared to CO40 and FO (p < 0.05), increased in monounsaturated fatty acids (p < 0.01), decreased in total ω3 fatty acids (FO > CO40 > CO80; p < 0.01) and increased in total ω6 fatty acids (FO < CO40 < CO80; p < 0.01). In the liver, long-chain (LC) PUFA such as 20:4ω6, 20:5ω3, 22:5ω3 and 22:6ω3 decreased when fish oil was removed from the diet (p < 0.05), and increased in 18-carbon fatty acids (p < 0.01). Camelina oil can reduce the amount of fish oil needed to meet lipid requirements, although replacing 80 % of fish oil reduced LC PUFAs in both tissues. A comparison of BF₃ and H₂SO₄ as catalysts to transmethylate cod liver and muscle lipids revealed small but significant differences in some fatty acid proportions.

  7. Seasonal variation in biomarkers in blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua): implications for environmental monitoring in the Barents Sea.

    PubMed

    Nahrgang, J; Brooks, S J; Evenset, A; Camus, L; Jonsson, M; Smith, T J; Lukina, J; Frantzen, M; Giarratano, E; Renaud, P E

    2013-02-01

    In the Barents Sea, the limited data on biological relevant indicators and their responses to various anthropogenic stressors have hindered the development of a consistent scientific basis for selecting indicator species and developing practical procedures for environmental monitoring. Accordingly, the main aim of the present study was to develop a common set of baseline values for contaminants and biomarkers in three species, and to identify their strengths and limitations in monitoring of the Barents Sea. Blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua) were sampled from a north Norwegian fjord in March, June, September and December 2010. Digestive glands from the bivalve species and liver from Atlantic cod were analysed for biomarkers of oxidative stress (catalase [CAT], glutathione peroxidase [GPX], glutathione-S-transferase activities [GST], lipid peroxidation as thiobarbituric reactive substances [TBARS] and total oxyradical scavenging capacity [TOSC]), biotransformation (ethoxyresorufine-O-deethylase activity [EROD]) and general stress (lysosomal membrane stability [LMS]). Concentrations of polycyclic aromatic hydrocarbons (PAHs) and metals in the bivalves and PAH metabolites in fish bile were quantified. Finally, energy reserves (total lipids, proteins and carbohydrates) and electron transport system (ETS) activity in the digestive gland of the bivalves and liver of Atlantic cod provided background information for reproductive cycle and general physiological status of the organisms. Blue mussel and Icelandic scallop showed very similar trends in biological cycle, biomarker expression and seasonality. Biomarker baselines in Atlantic cod showed weaker seasonal variability. However, important biological events may have been undetected due to the large time intervals between sampling occasions. Physiological biomarkers such as energy reserves and ETS activity were recommended as complementary parameters to the

  8. Genetic analysis of vibriosis and viral nervous necrosis resistance in Atlantic cod (Gadus morhua L.) using a cure model.

    PubMed

    Bangera, R; Ødegård, J; Nielsen, H M; Gjøen, H M; Mortensen, A

    2013-08-01

    The aim of this study was to investigate whether observed time-until-death of Atlantic cod (Gadus morhua L.) juveniles in separate challenge tests with Vibrio anguillarum (causes vibriosis) and nodavirus [causes viral nervous necrosis (VNN)] are due to differences in susceptibility (whether at risk or not) or increased endurance (individual hazard, given that the animal is susceptible) using a cure mixture (CURE) model with Gibbs sampling. Observed time-until-death, prepared as sequential binary records, were analyzed with the CURE model and results were compared with cross-sectional threshold (SIMPLE) and an ordinary longitudinal survival score (NAÏVE) model (i.e., assuming that all animals are susceptible). Overall mortality at the end of the test was 86 and 71% for vibriosis and VNN, respectively. But the CURE model estimated 92 and 82% of the population to be susceptible to vibriosis and VNN, respectively. Hence, a substantial fraction among the survivors were considered to be susceptible but with high endurance. The underlying heritability of susceptibility was moderate for vibriosis (0.33) and extremely high for VNN (0.91), somewhat greater compared with classical SIMPLE model (0.19 and 0.76 for vibriosis and VNN, respectively), analyzing end survival as a cross-sectional binary trait. Estimates of the underlying heritability were low for single test-day scores of both endurance (0.02 and 0.15 for vibriosis and VNN, respectively) in the CURE model and for the NAÏVE model (0.02 and 0.18 for vibriosis and VNN, respectively). Based on the CURE model, the genetic correlation between susceptibility and endurance was low to moderately positive and significantly different from unity (P < 0.01) for both vibriosis (0.13) and VNN (0.47). Estimated breeding values from the SIMPLE and NAÏVE models showed moderate to high correlations (0.41 to 0.96) with EBV for susceptibility and endurance in the CURE model. The analyses indicate that susceptibility and endurance are

  9. A new method for the rapid detection of Atlantic cod (Gadus morhua), Pacific cod (Gadus macrocephalus), Alaska pollock (Gadus chalcogrammus) and ling (Molva molva) using a lateral flow dipstick assay.

    PubMed

    Taboada, Ledicia; Sánchez, Ana; Pérez-Martín, Ricardo I; Sotelo, Carmen G

    2017-10-15

    Species-specific lateral flow dipstick (LFD) assays for the identification of Atlantic cod (Gadus morhua), Pacific cod (Gadus macrocephalus), Alaska pollock (Gadus chalcogrammus) and ling (Molva molva) in food products were developed. The method comprises a PCR system with four sets of specific primers, for each target species. This step was also devised to dual-labeling of PCR products with biotin and 6-FAM, which are then easily read on a lateral flow dipstick, upon which these products are immobilized by a fixed biotin-ligand and visualized with anti-FAM antibody-coated gold nanoparticles. Sensitivity and selectivity were determined for each of the developed assays. Validation of the assays was performed with DNA extracted from commercial fish products, the identification of all samples by PCR-LFD was coherent with the results found with DNA sequencing. Target species were successfully detected in analyzed commercial samples, demonstrating the applicability of this method to the rapid analysis of food products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. An evaluation of the duration of efficacy of emamectin benzoate in the control of Caligus curtus Müller infestations in Atlantic cod, Gadus morhua L.

    PubMed

    Hamre, L A; Lunestad, B T; Hannisdal, R; Samuelsen, O B

    2011-06-01

    The duration of efficacy of emamectin benzoate in the control of Caligus curtus infestations in Atlantic cod, Gadus morhua L., was studied following an administration of 50 μg kg⁻¹ for seven consecutive days. No lice were found on medicated fish when challenged 1 week (challenge 1) or 5 weeks (challenge 2) following termination of medication, whereas the mean abundance of lice among the unmedicated fish was 17.9 and 19.3 lice per fish in challenge 1 and 2, respectively. Muscle concentrations of 19.5 ± 8.2 ng g⁻¹ and 3.4 ± 0.9 ng g⁻¹, respectively, and skin concentrations of 23.1 ± 10.8 and 4.2 ± 1.0 ng g⁻¹, respectively, were found 27 and 55 days following the termination of medication. Tissue concentrations and the duration of efficacy indicate a dosing regime for emamectin in cod, similar to the regime used for Atlantic salmon, Salmo salar L. © 2011 Blackwell Publishing Ltd.

  11. Effects of oil pollution and persistent organic pollutants (POPs) on glycerophospholipids in liver and brain of male Atlantic cod (Gadus morhua).

    PubMed

    Bratberg, Mari; Olsvik, Pål A; Edvardsen, Rolf B; Brekken, Hans Kristian; Vadla, Reidun; Meier, Sonnich

    2013-02-01

    Fish in the North Sea are exposed to relatively high levels of halogenated compounds in addition to the pollutants released by oil production activities. In this study male Atlantic cod (Gadus morhua) were orally exposed to environmental realistic levels (low and high) of weathered crude oil and/or a mixture of POPs for 4weeks. Lipid composition in brain and in liver extracts were analysed in order to assess the effects of the various pollutants on membrane lipid composition and fatty acid profiles. Transcriptional effects in the liver were studied by microarray and quantitative real-time RT-PCR. Chemical analyses confirmed uptake of polychlorinated biphenyls (PCBs) and chlorinated pesticides, polybrominated diphenyl ethers (PBDEs) and perfluorooctanesulfonate (PFOS) in the liver and excretion of metabolites of polyaromatic hydrocarbons (PAHs) in the bile. Treatment with POPs and/or crude oil did not induce significant changes in lipid composition in cod liver. Only a few minor changes were observed in the fatty acid profile of the brain and the lipid classes in the liver. The hypothesis that pollution from oil or POPs at environmental realistic levels alters the lipid composition in marine fish was therefore not confirmed in this study. However, the transcriptional data suggest that the fish were affected by the treatment at the mRNA level. This study suggests that a combination of oil and POPs induce the CYP1a detoxification system and gives an increase in the metabolism and clearing rate of PAHs and POPs, but with no effects on membrane lipids in male Atlantic cod. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Ontogenetic effects of diet during early development on growth performance, myosin mRNA expression and metabolic enzyme activity in Atlantic cod juveniles reared at different salinities.

    PubMed

    Koedijk, Roland M; Le François, Nathalie R; Blier, Pierre U; Foss, Atle; Folkvord, Arild; Ditlecadet, Delphine; Lamarre, Simon G; Stefansson, Sigurd O; Imsland, Albert K

    2010-05-01

    This study investigates the effect of diet during early development on growth and metabolic capacity in the juvenile stage of Atlantic cod. Growth in three groups of Atlantic cod juveniles (10-70 g) was measured at two salinities (15 per thousand or 32 per thousand) in combination with two temperatures (10 degrees C or 14 degrees C). Groups of cod from a single egg batch differed by having been fed with rotifers (R) or natural zooplankton (Z) during the first 36 days post hatch. A third group was fed zooplankton from 1 to 22 dph, after which diet changed to rotifers from 22 to 36 dph (ZRZ). All fish were weaned at 36 dph. Juveniles from the Z and ZRZ groups performed equally well under all experimental conditions, but fish that had received rotifers as a larval diet showed overall significantly lower growth rates. Growth was significantly enhanced by reduced salinity. Metabolic enzyme activity and relative myosin mRNA expression levels were not affected by larval diet. Muscle AAT and MDH were affected by salinity while these enzymes in liver tissue were affected by the interaction between salinity and temperature. Metabolic enzymes were stronger correlated with fish size than growth rates. Our results indicate that larval diet has a pronounced effect on juvenile growth rates under varying environmental conditions as optimal larval diet (zooplankton) increased juvenile growth rates significantly. Metabolic enzyme activity and relative myosin mRNA expression were not affected by larval history, which suggests that the persisting juvenile growth difference is not a result of differing metabolic capacity.

  13. Differential Survival among Batches of Atlantic Cod (Gadus morhua L.) from Fertilisation through to Post-Metamorphosis.

    PubMed

    Petersen, Petra E; Penman, David J; Dahle, Geir; Patursson, Øystein; Taggart, John B

    2016-01-01

    Aquaculture production of cod has decreased from over 20,000 tonnes in 2009 to less than 2,000 tonnes in 2014 and the industry faces many challenges, one of which is high and unpredictably variable mortality rates in the early life stages. Hence, full-cycle farming with hatchery produced juveniles is still considered unprofitable compared to fisheries and on-growing of wild cod. In the present study, potential batch differences in progeny survival of wild-caught, hatchery-spawned Faroe Bank cod (Gadus morhua L.) were investigated at two defined periods during early life history; i) the embryo stage (60 day degrees post fertilisation) and ii) the fry stage (110 days post hatch), post metamorphosis. The fry stage experiment was conducted in three replicates (N = 300 per replicate), and a panel of three polymorphic microsatellite markers was used for parental analysis. Mean survival rate at the embryo stage was 69% (± 20% SD). Survival was positively associated with egg diameter (P < 0.01), explaining 90% of the variation in egg survival rates. The data were too scarce to conclude either way concerning a possible correlation between survival rates between the two periods (P < 0.10). Offspring from three batches (from a total of eight) dominated in the fry stage, contributing over 90% of the progeny, and results were consistent over all three replicate tanks. The skewed batch representation observed may be of relevance to the effective management of selective breeding programmes for cod.

  14. Differential Survival among Batches of Atlantic Cod (Gadus morhua L.) from Fertilisation through to Post-Metamorphosis

    PubMed Central

    Petersen, Petra E.; Penman, David J.; Dahle, Geir; Patursson, Øystein; Taggart, John B.

    2016-01-01

    Aquaculture production of cod has decreased from over 20,000 tonnes in 2009 to less than 2,000 tonnes in 2014 and the industry faces many challenges, one of which is high and unpredictably variable mortality rates in the early life stages. Hence, full-cycle farming with hatchery produced juveniles is still considered unprofitable compared to fisheries and on-growing of wild cod. In the present study, potential batch differences in progeny survival of wild-caught, hatchery-spawned Faroe Bank cod (Gadus morhua L.) were investigated at two defined periods during early life history; i) the embryo stage (60 day degrees post fertilisation) and ii) the fry stage (110 days post hatch), post metamorphosis. The fry stage experiment was conducted in three replicates (N = 300 per replicate), and a panel of three polymorphic microsatellite markers was used for parental analysis. Mean survival rate at the embryo stage was 69% (± 20% SD). Survival was positively associated with egg diameter (P < 0.01), explaining 90% of the variation in egg survival rates. The data were too scarce to conclude either way concerning a possible correlation between survival rates between the two periods (P < 0.10). Offspring from three batches (from a total of eight) dominated in the fry stage, contributing over 90% of the progeny, and results were consistent over all three replicate tanks. The skewed batch representation observed may be of relevance to the effective management of selective breeding programmes for cod. PMID:27362346

  15. Identification of Atlantic cod (Gadus morhua), ling (Molva molva), and Alaska pollock (Gadus chalcogrammus) by PCR-ELISA using duplex PCR.

    PubMed

    Taboada, Ledicia; Sánchez, Ana; Velasco, Amaya; Santaclara, Francisco J; Pérez-Martín, Ricardo I; Sotelo, Carmen G

    2014-06-18

    Species-specific PCR-ELISA assays for the identification of Atlantic cod (Gadus morhua), Alaska pollock (Gadus chalcogrammus), and ling (Molva molva) in food products have been developed. The method, comprising a set of primers common to the first two species, a set of primers for M. molva, and a probe for each species, was designed using ND4 and cytochrome b genes as molecular markers. The sensitivity and selectivity were then determined for each assay. These assays were afterward used to analyze DNA extracted from commercial fish products. The presence of the target species was successfully detected in all analyzed samples, demonstrating the applicability of this method to the analysis of food products.

  16. Environmental harm assessment of a wastewater discharge from Hammerfest LNG: a study with biomarkers in mussels (Mytilus sp.) and Atlantic cod (Gadus morhua).

    PubMed

    Beyer, Jonny; Aarab, Nadia; Tandberg, Anne Helene; Ingvarsdottir, Anna; Bamber, Shaw; Børseth, Jan Fredrik; Camus, Lionel; Velvin, Roger

    2013-04-15

    Biologically treated wastewater (WW) from the Hammerfest LNG (liquefied natural gas) plant is discharged to the sea. A study using biomarkers in mussels and Atlantic cod was performed to examine whether this discharge meets a zero harmful emission requirement. Caging of mussels close to the outfall and exposure of mussels and fish to WW in the laboratory were conducted, and a suite of contaminant responsive markers was assessed in exposed animals. In mussels the markers included chemical contaminant levels, haemocyte lysosomal instability and nucleus integrity, cellular energy allocation, digestive gland and gonad histopathology and shell-opening behaviour. In fish, biliary PAH metabolites and gill histopathology biomarkers were measured. A consistent cause-effect relationship between WW treatments and markers measured in test animals was not found. The results therefore indicate that the WW emission is unlikely to represent a significant stress factor for the local marine environment under the conditions studied.

  17. Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae — can we identify the underlying factors?

    PubMed Central

    van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trina F.; Kjørsvik, Elin; Hamre, Kristin

    2015-01-01

    The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were conducted in order to identify the underlying factors for this phenomenon. In the first experiment (Exp-1), groups of cod larvae were fed either (a) natural zooplankton, mainly copepods, increasing the size of prey as the larvae grew or (b) enriched rotifers followed by Artemia (the intensive group). In the second experiment (Exp-2), two groups of larvae were fed as in Exp-1, while a third group was fed copepod nauplii (approximately the size of rotifers) throughout the larval stage. In both experiments, growth was not significantly different between the groups during the first three weeks after hatching, but from the last part of the rotifer feeding period and onwards, the growth of the larvae fed copepods was higher than that of the intensive group. In Exp-2, the growth was similar between the two copepod groups during the expeimental period, indicating that nutrient composition, not prey size caused the better growth on copepods. Analyses of the prey showed that total fatty acid composition and the ratio of phospholipids to total lipids was slightly different in the prey organisms, and that protein, taurine, astaxanthin and zinc were lower on a dry weight basis in rotifers than in copepods. Other measured nutrients as DHA, all analysed vitamins, manganese, copper and selenium were similar or higher in the rotifers. When compared to the present knowledge on nutrient requirements, protein and taurine appeared to be the most likely limiting nutrients for growth in cod larvae fed rotifers and Artemia. Larvae fed rotifers/Artemia had a higher whole body lipid content than larvae fed copepods at the end of the experiment (stage 5) after the fish had been fed the same formulated diet for approximately 2 weeks. PMID:26038712

  18. Molecular cloning and measurement of telomerase reverse transcriptase (TERT) transcription patterns in tissues of European hake (Merluccius merluccius) and Atlantic cod (Gadus morhua) during aging.

    PubMed

    López de Abechuco, E; Bilbao, E; Soto, M; Díez, G

    2014-05-10

    Telomerase is a reverse transcriptase ribonucleoprotein that maintains the ends of linear chromosomes. This enzyme plays a major role in cell processes like proliferation, differentiation and tumorigenesis, being associated with aging and survival of species. In this study, the gene coding for TERT (Telomerase Reverse Transcriptase) of two commercial fish species, European hake (Merluccius merluccius) and Atlantic cod (Gadus morhua), has been partially cloned. A fragment of 1581bp (hake) and 633bp (cod) showed high homology (identity 74%, query cover 99%, E-value=0) with known Perciformes TERT sequences. TERT transcription patterns were assessed by qRT-PCR in different tissues of hake (brain, ovary, testis, muscle, skin, gills, liver and kidney) and cod (brain, muscle and skin) of different sizes/ages in order to understand its role in the physiological aging of teleosts. TERT was found to be ubiquitously transcribed in all tissues and size/age groups studied in both species. Significantly higher relative transcription levels (p<0.05) were found with increasing size/age of M. merluccius in the kidney, muscle, skin and gonad, the latter exhibiting particularly high relative transcription levels. Male hakes showed higher TERT relative transcription levels in the brain, gonad and liver than females, although these differences were not statistically significant (p<0.05). In G. morhua, higher TERT relative transcription levels were recorded in the muscle and brain of fry and juvenile individuals. Therefore, TERT relative transcription pattern exhibited a higher telomerase demand in early developmental stages and also in mature stages, suggesting tissue renewal or regeneration processes as a conserved mechanism for maintaining long-term cell proliferation capacity and preventing senescence. Thus, it can be concluded that TERT relative transcription level was species and tissue specific and changed with the age of fishes.

  19. Pituitary gonadotropin and testicular gonadotropin receptor expression in Atlantic cod (Gadusmorhua L.) during the first reproductive season: Effects of photoperiod modulation.

    PubMed

    de Almeida, Fernanda Ferreira Loureiro; Andersson, Eva; Mittelholzer, Christian; Karlsen, Orjan; Taranger, Geir Lasse; Schulz, Rüdiger W

    2011-08-01

    Pituitary mRNA levels of gonadotropin β-subunits and of their cognate receptors in the testis were studied during puberty in Atlantic cod under normal and experimental photoperiod conditions that suppressed, delayed or accelerated testis maturation. Results are discussed in context with changes in testicular histology and plasma androgen levels, considered as end points of gonadotropic regulation. Up-regulation of fshb was closely associated with the onset of puberty, decreased when spermatogenesis was completed and reached minimum levels after spawning. These results demonstrate, for the first time using an experimental approach, that activation of Fsh-dependent signaling is associated with spermatogonial proliferation and formation of spermatogenic cysts. Changes in fshr expression were less prominent and could be explained by changes in the cellular composition and RNA content of cod testis tissue. At more advanced stages of development (spermiogenesis, spermiation and spawning), lhb and, one month later, lhcgr transcript levels increased and reached peak values in spawning fish, in a positive feedback loop involving plasma androgens and Lh/Lhcgr-dependent signaling. This loop was broken by a loss of lhb expression at the end of the spawning season. Continuous light (LL) from summer solstice, ~8 months prior to spawning, suppressed the start of testis maturation and the changes in gonadotropin and receptor mRNA levels, while LL from winter solstice initially up-regulated lhb and lhcgr expression, before resulting in a precocious termination of the spawning season and low expression of all four genes. Our studies provide experimental evidence for a clear functional discrimination of cod gonadotropins. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Pre-digestion of dietary lipids has only minor effects on absorption, retention and metabolism in larval stages of Atlantic cod (Gadus morhua).

    PubMed

    Hamre, K; Lukram, I M; Rønnestad, I; Nordgreen, A; Saele, O

    2011-03-01

    The hypothesis of the present study was that cod larvae have a limitation in lipid digestion, and that absorption of lipids would increase by pre-hydrolysation. The diets used were designed to contain 15% lipid, of which 40% was phosphatidylcholine (PC) and 60 % was TAG. Cod larvae (40d post hatch (dph)) were fed a single meal where either PC or TAG was radioactively labelled, and the labelled PC or TAG was either intact or hydrolysed (pre-digested). The larvae were then incubated individually in chambers with collection of CO2 for 10 h. The following fractions were analysed for radioactivity: the incubation water (evacuated feed); the intestine; the body; the CO2 trap. The larvae ate a 16-29 μg diet, equivalent to 3·4-5·2 % of dry body weight. In the whole population, 0-16% of the lipid was evacuated. The larvae that had eaten less than 1·9-2·7 μg lipid absorbed close to 100% of the lipid, absorption being defined conservatively as the amount contained in the carcass and CO2, excluding the intestinal tissue. In these larvae, approximately 100 % of the absorbed lipid was also catabolised. In the larvae that ingested more than 1·9-2·7 μg lipid, there was a linear reduction in lipid absorption to a minimum of 55% at the highest lipid intakes parallel to an increasing retention of lipids in the carcass. There were only minor differences in digestion, absorption, retention and metabolism of lipids between the larvae fed the different diets, and the larvae tended to retain lipid classes as they were present in the feed. The study shows that 40-dph Atlantic cod larvae have an efficient utilisation of dietary lipids supplied as intact PC and TAG.

  1. The blood volumes of the primary and secondary circulatory system in the Atlantic cod Gadus morhua L, using plasma bound Evans Blue and compartmental analysis.

    PubMed

    Skov, P V; Steffensen, J F

    2003-02-01

    The volume of the primary (PCS) and secondary (SCS) circulatory system in the Atlantic cod Gadus morhua was determined using a modified dye dilution technique. Cod (N=10) were chronically cannulated in the second afferent branchial artery with PE-50 tubing. Evans Blue dye was bound to harvested fish plasma at a concentration of 1 mg dye ml(-1) plasma, and injected at a concentration of 1 mg kg(-1) body mass. Serial sampling from the cannula produced a dye dilution curve, which could be described by a double exponential decay equation. Curve analysis enabled the calculation of the primary circulatory and total distribution volume. The difference between these volumes is assumed to be the volume of the SCS. From the dilution curve, it was also possible to calculate flow rates between and within the systems. The results of these experiments suggest a plasma volume in the PCS of 3.42+/-0.89 ml 100 g(-1) body mass, and in the SCS of 1.68+/-0.35 ml 100 g(-1) body mass (mean +/- S.D.) or approximately 50% that of the PCS. Flow rates to the SCS were calculated as 2.7% of the resting cardiac output. There was an allometric relationship between body mass and blood volumes. Increasing condition factor showed a tendency towards smaller blood volumes of the PCS, expressed as percentage body mass, but this was not evident for the volume of the SCS.

  2. Screening and characterisation of potentially pathogenic bacteria associated with Atlantic cod Gadus morhua larvae: bath challenge trials using a multidish system.

    PubMed

    Sandlund, Nina; Bergh, Øivind

    2008-09-24

    In intensive aquaculture systems, high concentrations of nutrients and high densities of fish larvae provide favorable conditions for opportunistic pathogenic bacteria to flourish. We screened potentially pathogenic bacterial strains isolated from moribund Atlantic cod Gadus morhua larvae, pollack Pollachius pollachius, coalfish Pollachius virens, Atlantic halibut Hippoglossus hippoglossus, rotifers, algae and water samples from different hatcheries. Three identical challenge experiments tested a total of 53 strains. A multidish system was used: cod eggs were placed in single wells, together with 2 ml of sterile seawater, and exposed to the bacterial cultures. Final bacterial concentrations in the wells were 10(6) and 10(4) CFU ml(-1). Eggs and larvae not exposed to bacteria were used as unchallenged controls. Challenged controls were exposed to Vibrio anguillarum strain 610. Eggs were challenged approximately 48 h prior to hatching and mortality was recorded daily throughout the yolk-sac period. In spite of the high challenge dose of 106 CFU ml(-1), only 5 bacterial strains tested caused higher mortality than the unchallenged controls. Four of these strains were identified by 16S rDNA and gyrase B gene (GyrB) sequencing as resembling V. anguillarum and 1 strain resembled Carnobacterium sp. Most of the larvae exposed to these strains died within 10 d of challenge. Serotyping of the strains resembling V. anguillarum gave inconclusive results. This indicates differences in serology compared to the serotypes O1, O2 and O3, associated with disease. Three bacterial strains seemed to have a slower infection rate, indicating a longer incubation period. The remaining 45 strains did not seem to have a negative effect on larval survival, suggesting that these are not primary pathogens.

  3. Quantitative proteomics analysis reveals perturbation of lipid metabolic pathways in the liver of Atlantic cod (Gadus morhua) treated with PCB 153.

    PubMed

    Yadetie, Fekadu; Oveland, Eystein; Døskeland, Anne; Berven, Frode; Goksøyr, Anders; Karlsen, Odd André

    2017-04-01

    PCB 153 is one of the most abundant PCB congeners detected in biological samples. It is a persistent compound that is still present in the environment despite the ban on production and use of PCBs in the late 1970s. It has strong tendencies to bioaccumulate and biomagnify in biota, and studies have suggested that it is an endocrine and metabolic disruptor. In order to study mechanisms of toxicity, we exposed Atlantic cod (Gadus morhua) to various doses of PCB 153 (0, 0.5, 2 and 8mg/kg body weight) for two weeks and examined the effects on expression of liver proteins using label-free quantitative proteomics. Label-free liquid chromatography-mass spectrometry analysis of the liver proteome resulted in the quantification of 1272 proteins, of which 78 proteins were differentially regulated in the PCB 153-treated dose groups compared to the control group. Functional enrichment analysis showed that pathways significantly affected are related to lipid metabolism, cytoskeletal remodeling, cell cycle and cell adhesion. Importantly, the main effects appear to be on lipid metabolism, with up-regulation of enzymes in the de novo fatty acid synthesis pathway, consistent with previous transcriptomics results. Increased plasma triglyceride levels were also observed in the PCB 153 treated fish, in agreement with the induction of the lipogenic genes and proteins. The results suggest that PCB 153 perturbs lipid metabolism in the Atlantic cod liver. Elevated levels of lipogenic enzymes and plasma triglycerides further suggest increased synthesis of fatty acids and triglycerides. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Francisella noatunensis subsp. noatunensis replicates within Atlantic cod (Gadus morhua L.) leucocytes and inhibits respiratory burst activity.

    PubMed

    Vestvik, Nils; Rønneseth, Anita; Kalgraff, Cathrine A K; Winther-Larsen, Hanne C; Wergeland, Heidrun I; Haugland, Gyri T

    2013-09-01

    Francisella noatunensis subsp. noatunensis, causing granulomatosis in cod, has been shown to reside within cod immune cells, mainly within monocytes and macrophages. In the present study, we analysed the ability of the bacterium to replicate within adherent cells isolated from head kidney by in vitro infection of leucocytes. Two different technical approaches for flow cytometry analyses were performed for detection of intracellular bacteria. The presence of the wild type was assessed after identification by intracellular binding of specific antibodies to the pathogen. The other way was to use green fluorescent protein (GFP) transformed bacterium for infection studies allowing direct measurements of fluorescence from infected cells. By both methods we found an increase in fluorescence in infected cells, verifying bacterial replication, both after 4 and 28 h post infection in leucocytes isolated from head kidney (HKL). The GFP transformed bacterium was similar to the wild type in growth and infectivity pattern, showing that it can be a valuable tool for further studies of infection routes and pathology. Further, F. noatunensis subsp. noatunensis was found to inhibit respiratory burst activity, a potent pathogen killing mechanism, in cod leucocytes, but not in such cells from salmon. Our findings may indicate that inhibition of respiratory burst during Francisella infection is a key to its intracellular existence. This strategy seems to be conserved through evolution as it is also observed during infections in higher vertebrates caused by bacteria within the Francisella genus. The results presented here, showing the intracellular existence of Francisella, its replication within leucocytes and the inhibitory effect on respiratory burst, strongly support that these factors contribute to disease and pathology in infected cod. The intracellular replication shown in the present study might contribute to explain the problems of obtaining protective vaccines against

  5. The Ontogeny and Brain Distribution Dynamics of the Appetite Regulators NPY, CART and pOX in Larval Atlantic Cod (Gadus morhua L.).

    PubMed

    Le, Hoang T M D; Angotzi, Anna Rita; Ebbesson, Lars O E; Karlsen, Ørjan; Rønnestad, Ivar

    2016-01-01

    Similar to many marine teleost species, Atlantic cod undergo remarkable physiological changes during the early life stages with concurrent and profound changes in feeding biology and ecology. In contrast to the digestive system, very little is known about the ontogeny and the localization of the centers that control appetite and feed ingestion in the developing brain of fish. We examined the expression patterns of three appetite regulating factors (orexigenic: neuropeptide Y, NPY; prepro-orexin, pOX and anorexigenic: cocaine- and amphetamine-regulated transcript, CART) in discrete brain regions of developing Atlantic cod using chromogenic and double fluorescent in situ hybridization. Differential temporal and spatial expression patterns for each appetite regulator were found from first feeding (4 days post hatch; dph) to juvenile stage (76 dph). Neurons expressing NPY mRNA were detected in the telencephalon (highest expression), diencephalon, and optic tectum from 4 dph onward. CART mRNA expression had a wider distribution along the anterior-posterior brain axis, including both telencephalon and diencephalon from 4 dph. From 46 dph, CART transcripts were also detected in the olfactory bulb, region of the nucleus of medial longitudinal fascicle, optic tectum and midbrain tegmentum. At 4 and 20 dph, pOX mRNA expression was exclusively found in the preoptic region, but extended to the hypothalamus at 46 and 76 dph. Co-expression of both CART and pOX genes were also observed in several hypothalamic neurons throughout larval development. Our results show that both orexigenic and anorexigenic factors are present in the telencephalon, diencephalon and mesencephalon in cod larvae. The telencephalon mostly contains key factors of hunger control (NPY), while the diencephalon, and particularly the hypothalamus may have a more complex role in modulating the multifunctional control of appetite in this species. As the larvae develop, the overall progression in temporal and

  6. The Ontogeny and Brain Distribution Dynamics of the Appetite Regulators NPY, CART and pOX in Larval Atlantic Cod (Gadus morhua L.)

    PubMed Central

    Le, Hoang T. M. D.; Angotzi, Anna Rita; Ebbesson, Lars O. E.; Karlsen, Ørjan

    2016-01-01

    Similar to many marine teleost species, Atlantic cod undergo remarkable physiological changes during the early life stages with concurrent and profound changes in feeding biology and ecology. In contrast to the digestive system, very little is known about the ontogeny and the localization of the centers that control appetite and feed ingestion in the developing brain of fish. We examined the expression patterns of three appetite regulating factors (orexigenic: neuropeptide Y, NPY; prepro-orexin, pOX and anorexigenic: cocaine- and amphetamine-regulated transcript, CART) in discrete brain regions of developing Atlantic cod using chromogenic and double fluorescent in situ hybridization. Differential temporal and spatial expression patterns for each appetite regulator were found from first feeding (4 days post hatch; dph) to juvenile stage (76 dph). Neurons expressing NPY mRNA were detected in the telencephalon (highest expression), diencephalon, and optic tectum from 4 dph onward. CART mRNA expression had a wider distribution along the anterior-posterior brain axis, including both telencephalon and diencephalon from 4 dph. From 46 dph, CART transcripts were also detected in the olfactory bulb, region of the nucleus of medial longitudinal fascicle, optic tectum and midbrain tegmentum. At 4 and 20 dph, pOX mRNA expression was exclusively found in the preoptic region, but extended to the hypothalamus at 46 and 76 dph. Co-expression of both CART and pOX genes were also observed in several hypothalamic neurons throughout larval development. Our results show that both orexigenic and anorexigenic factors are present in the telencephalon, diencephalon and mesencephalon in cod larvae. The telencephalon mostly contains key factors of hunger control (NPY), while the diencephalon, and particularly the hypothalamus may have a more complex role in modulating the multifunctional control of appetite in this species. As the larvae develop, the overall progression in temporal and

  7. Cape Cod

    Atmospheric Science Data Center

    2014-05-15

    article title:  Cape Cod, Massachusetts     View Larger ... Pilgrims landed, is located on the west side of Cape Cod Bay, shown in this Multi-angle Imaging SpectroRadiometer (MISR) ... Terra orbit 1708. South of the distinctively-shaped Cape Cod are Nantucket Island and Martha's Vineyard. Further west is Block Island, ...

  8. Effect of sub-lethal exposure to ultraviolet radiation on the escape performance of Atlantic cod larvae (Gadus morhua).

    PubMed

    Fukunishi, Yuichi; Browman, Howard I; Durif, Caroline M F; Bjelland, Reidun M; Skiftesvik, Anne Berit

    2012-01-01

    The amount of ultraviolet (UV) radiation reaching the earth's surface has increased due to depletion of the ozone layer. Several studies have reported that UV radiation reduces survival of fish larvae. However, indirect and sub-lethal impacts of UV radiation on fish behavior have been given little consideration. We observed the escape performance of larval cod (24 dph, SL: 7.6±0.2 mm; 29 dph, SL: 8.2±0.3 mm) that had been exposed to sub-lethal levels of UV radiation vs. unexposed controls. Two predators were used (in separate experiments): two-spotted goby (Gobiusculus flavescens; a suction predator) and lion's mane jellyfish (Cyanea capillata; a "passive" ambush predator). Ten cod larvae were observed in the presence of a predator for 20 minutes using a digital video camera. Trials were replicated 4 times for goby and 5 times for jellyfish. Escape rate (total number of escapes/total number of attacks ×100), escape distance and the number of larvae remaining at the end of the experiment were measured. In the experiment with gobies, in the UV-treated larvae, both escape rate and escape distance (36%, 38±7.5 mm respectively) were significantly lower than those of control larvae (75%, 69±4.7 mm respectively). There was a significant difference in survival as well (UV: 35%, 63%). No apparent escape response was observed, and survival rate was not significantly different, between treatments (UV: 66%, 74%) in the experiment with jellyfish. We conclude that the effect and impact of exposure to sub-lethal levels of UV radiation on the escape performance of cod larvae depends on the type of predator. Our results also suggest that prediction of UV impacts on fish larvae based only on direct effects are underestimations.

  9. Effect of Sub-Lethal Exposure to Ultraviolet Radiation on the Escape Performance of Atlantic Cod Larvae (Gadus morhua)

    PubMed Central

    Fukunishi, Yuichi; Browman, Howard I.; Durif, Caroline M. F.; Bjelland, Reidun M.; Skiftesvik, Anne Berit

    2012-01-01

    The amount of ultraviolet (UV) radiation reaching the earth's surface has increased due to depletion of the ozone layer. Several studies have reported that UV radiation reduces survival of fish larvae. However, indirect and sub-lethal impacts of UV radiation on fish behavior have been given little consideration. We observed the escape performance of larval cod (24 dph, SL: 7.6±0.2 mm; 29 dph, SL: 8.2±0.3 mm) that had been exposed to sub-lethal levels of UV radiation vs. unexposed controls. Two predators were used (in separate experiments): two-spotted goby (Gobiusculus flavescens; a suction predator) and lion's mane jellyfish (Cyanea capillata; a “passive" ambush predator). Ten cod larvae were observed in the presence of a predator for 20 minutes using a digital video camera. Trials were replicated 4 times for goby and 5 times for jellyfish. Escape rate (total number of escapes/total number of attacks ×100), escape distance and the number of larvae remaining at the end of the experiment were measured. In the experiment with gobies, in the UV-treated larvae, both escape rate and escape distance (36%, 38±7.5 mm respectively) were significantly lower than those of control larvae (75%, 69±4.7 mm respectively). There was a significant difference in survival as well (UV: 35%, Control: 63%). No apparent escape response was observed, and survival rate was not significantly different, between treatments (UV: 66%, Control: 74%) in the experiment with jellyfish. We conclude that the effect and impact of exposure to sub-lethal levels of UV radiation on the escape performance of cod larvae depends on the type of predator. Our results also suggest that prediction of UV impacts on fish larvae based only on direct effects are underestimations. PMID:22536406

  10. Suspended matter in surface waters of the Atlantic continental margin from Cape Cod to the Florida Keys.

    PubMed

    Manheim, F T; Meade, R H; Bond, G C

    1970-01-23

    Appreciable Amounts Of suspended matter (> 1.0 milligram per liter) in surface waters are restricted to within a few kilometers of the Atlantic coast. Particles that escape estuaries or are discharged by rivers into the shelf region tend to travel longshoreward rather than seaward. Suspended matter farther offshore, chiefly amorphous organic particles, totals 0.1 milligram per liter or less. Soot, fly ash, processed cellulose, and other pollutants are widespread.

  11. Suspended matter in surface waters of the Atlantic continental margin from Cape Cod to the Florida keys

    USGS Publications Warehouse

    Manheim, F. T.; Meade, R.H.; Bond, G.C.

    1970-01-01

    Appreciable amounts of suspended matter (> 1.0 milligram per liter) in surface waters are restricted to within a few kilometers of the Atlantic coast. Particles that escape estuaries or are discharged by rivers into the shelf region tend to travel longshoreward rather than seaward. Suspended matter farther offshore, chiefly amorphous organic particles, totals 0.1 milligram per liter or less. Soot, fly ash, processed cellulose, and other pollutants are widespread.

  12. Atlantic cod (Gadus morhua) larvae can biosynthesis phospholipid de novo from 2-oleoyl-glycerol and glycerol precursors.

    PubMed

    Li, Keshuai; Olsen, Rolf Erik; Østensen, Mari-Ann; Altin, Dag; Kjørsvik, Elin; Olsen, Yngvar

    2016-02-01

    The dietary requirement of phospholipid (PL) of fish larvae has been suggested to originate in an inefficient ability for de novo biosynthesis of PL based on dietary triacylglycerol (TAG). The main objective of the present study was to investigate whether cod larvae could synthesis PL from sn-2-monoacylglycerol (2-MAG) and glycerol precursors. A tube feeding method was used to deliver equal molar aliquots of 2-oleoyl-[1,2,3-(3)H]glycerol and [U-(14)C] glycerol together with bovine serum albumin (BSA) bound 16:0 (palmitic acid) and 22:6n-3 (docosahexaenoic acid, DHA), with or without choline chloride to the foregut of anesthetized cod larvae and thereafter monitoring the metabolism of these components in the larvae through 4 h following injection. Our results showed that both 2-MAG and glycerol precursors contributed to the de novo synthesis of phosphatidylcholine (PC) and the 2-MAG pathway predominated over the G-3-P (glycerol-3-phosphate) pathway in the synthesis of TAG and PC. The molecular ratio of PC/TAG obtained from the 2-MAG and the G-3-P pathways was 0.44-0.74 and 1.02-2.06 within the first hour of tube feeding, suggesting they might have comparable biosynthesis ability of PC and TAG under the conditions of the present study. Furthermore, supplementation of choline chloride significantly increased PC/TAG ratio (p < 0.05) for both pathways. However, further studies are needed to quantify the enzyme activity involved in the CDP-choline (cytidine diphosphate choline) pathway, and the function of choline either in simulating PC synthesis or TAG catabolism or both needs further investigation.

  13. Progress of co-infections of Trichodina cooperi and T. murmanica parasitising farmed Atlantic cod Gadus morhua juveniles in Iceland.

    PubMed

    Kristmundsson, A; Eydal, M; Helgason, S

    2006-08-30

    Two year classes of wild cod juveniles, caught for on-rearing in shore-based tanks, were examined for Trichodina spp. infections at regular intervals for 9 mo. The prevalence, density and proportion of each species found was determined. Additionally, biomass, seawater temperature and salinity in the tanks was recorded regularly. Two species were identified: T. cooperi and T. murmanica. Their prevalence, density and proportion varied between sampling times, T. cooperi being the dominant species, more prevalent and in higher density in the beginning. In the following months, T. murmanica gradually increased its prevalence, density and proportion, reaching an almost total dominance in both year classes after 7 mo of rearing. The results indicate that the rearing environment on this farm favoured T. murmanica. Changes in salinity could explain this to some extent; a drop in salinity, due to an inflow of geothermal freshwater to control the temperature during the coldest months, coincided fairly well with an increasing proportion of T. murmanica. Transfer of wild fish into the rearing environment, with a subsequent increase in biomass, resulted in a proliferation of trichodinids. This may have altered the interaction between species and the competition for resources. It is conceivable that a higher host density favours one Trichodina species over the other. Temperature could also play a role. During the first 3 to 4 mo of rearing, the temperature in the tanks followed the temperature of the open sea, which dropped by 3 to 5 degrees C. This study is a part of a larger project on monitoring the progress of various infectious diseases in farmed cod of wild origin.

  14. Adjustments of molecular key components of branchial ion and pH regulation in Atlantic cod (Gadus morhua) in response to ocean acidification and warming.

    PubMed

    Michael, Katharina; Kreiss, Cornelia M; Hu, Marian Y; Koschnick, Nils; Bickmeyer, Ulf; Dupont, Sam; Pörtner, Hans-O; Lucassen, Magnus

    2016-03-01

    Marine teleost fish sustain compensation of extracellular pH after exposure to hypercapnia by means of efficient ion and acid-base regulation. Elevated rates of ion and acid-base regulation under hypercapnia may be stimulated further by elevated temperature. Here, we characterized the regulation of transepithelial ion transporters (NKCC1, NBC1, SLC26A6, NHE1 and 2) and ATPases (Na(+)/K(+) ATPase and V-type H(+) ATPase) in gills of Atlantic cod (Gadus morhua) after 4 weeks of exposure to ambient and future PCO2 levels (550 μatm, 1200 μatm, 2200 μatm) at optimum (10 °C) and summer maximum temperature (18 °C), respectively. Gene expression of most branchial ion transporters revealed temperature- and dose-dependent responses to elevated PCO2. Transcriptional regulation resulted in stable protein expression at 10 °C, whereas expression of most transport proteins increased at medium PCO2 and 18 °C. mRNA and protein expression of distinct ion transport proteins were closely co-regulated, substantiating cellular functional relationships. Na(+)/K(+) ATPase capacities were PCO2 independent, but increased with acclimation temperature, whereas H(+) ATPase capacities were thermally compensated but decreased at medium PCO2 and 10 °C. When functional capacities of branchial ATPases were compared with mitochondrial F1Fo ATP-synthase strong correlations of F1Fo ATP-synthase and ATPase capacities generally indicate close coordination of branchial aerobic ATP demand and supply. Our data indicate physiological plasticity in the gills of cod to adjust to a warming, acidifying ocean within limits. In light of the interacting and non-linear, dose-dependent effects of both climate factors the role of these mechanisms in shaping resilience under climate change remains to be explored.

  15. Quantitative analyses of the hepatic proteome of methylmercury-exposed Atlantic cod (Gadus morhua) suggest oxidative stress-mediated effects on cellular energy metabolism.

    PubMed

    Yadetie, Fekadu; Bjørneklett, Silje; Garberg, Hilde Kristin; Oveland, Eystein; Berven, Frode; Goksøyr, Anders; Karlsen, Odd André

    2016-08-05

    Methylmecury (MeHg) is a widely distributed environmental pollutant with considerable risk to both human health and wildlife. To gain better insight into the underlying mechanisms of MeHg-mediated toxicity, we have used label-free quantitative mass spectrometry to analyze the liver proteome of Atlantic cod (Gadus morhua) exposed in vivo to MeHg (0, 0.5, 2 mg/kg body weight) for 2 weeks. Out of a toltal of 1143 proteins quantified, 125 proteins were differentially regulated between MeHg-treated samples and controls. Using various bioinformatics tools, we performed gene ontology, pathway and network enrichment analysis, which indicated that proteins and pathways mainly related to energy metabolism, antioxidant defense, cytoskeleton remodeling, and protein synthesis were regulated in the hepatic proteome after MeHg exposure. Comparison with previous gene expression data strengthened these results, and further supported that MeHg predominantly affects many energy metabolism pathways, presumably through its strong induction of oxidative stress. Some enzymes known to have functionally important oxidation-sensitive cysteine residues in other animals are among the differentially regulated proteins, suggesting their modulations by MeHg-induced oxidative stress. Integrated analysis of the proteomics dataset combined with previous gene expression dataset showed a more pronounced effect of MeHg on amino acid, glucose and fatty acid metabolic pathways, and suggested possible interactions of the cellular energy metabolism and antioxidant defense pathways. MeHg disrupts mainly redox homeostasis and energy generating metabolic pathways in cod liver. The energy pathways appear to be modulated through MeHg-induced oxidative stress, possibly mediated by oxidation sensitive enzymes.

  16. Molecular identification and transmission studies of X-cell parasites from Atlantic cod Gadus morhua (Gadiformes: Gadidae) and the northern black flounder Pseudopleuronectes obscurus (Pleuronectiformes: Pleuronectidae)

    PubMed Central

    2011-01-01

    Background Epidermal pseudotumours from Hippoglossoides dubius and Acanthogobius flavimanus in Japan and gill lesions in Limanda limanda from the UK have been shown to be caused by phylogenetically related protozoan parasites, known collectively as X-cells. However, the phylogenetic position of the X-cell group is not well supported within any of the existing protozoan phyla and they are currently thought to be members of the Alveolata. Ultrastructural features of X-cells in fish pseudotumours are somewhat limited and no typical environmental stages, such as spores or flagellated cells, have been observed. The life cycles for these parasites have not been demonstrated and it remains unknown how transmission to a new host occurs. In the present study, pseudobranchial pseudotumours from Atlantic cod, Gadus morhua, in Iceland and epidermal pseudotumours from the northern black flounder, Pseudopleuronectes obscurus, in Japan were used in experimental transmission studies to establish whether direct transmission of the parasite is achievable. In addition, X-cells from Atlantic cod were sequenced to confirm whether they are phylogenetically related to other X-cells and epidermal pseudotumours from the northern black flounder were analysed to establish whether the same parasite is responsible for infecting different flatfish species in Japan. Results Phylogenetic analyses of small subunit ribosomal DNA (SSU rDNA) sequence data from Atlantic cod X-cells show that they are a related parasite that occupies a basal position to the clade containing other X-cell parasites. The X-cell parasite causing epidermal pseudotumours in P. obscurus is the same parasite that causes pseudotumours in H. dubius. Direct, fish to fish, transmission of the X-cell parasites used in this study, via oral feeding or injection, was not achieved. Non-amoeboid X-cells are contained within discrete sac-like structures that are loosely attached to epidermal pseudotumours in flatfish; these X-cells are

  17. Computer vision-based evaluation of pre- and postrigor changes in size and shape of Atlantic cod (Gadus morhua) and Atlantic salmon (Salmo salar) fillets during rigor mortis and ice storage: effects of perimortem handling stress.

    PubMed

    Misimi, E; Erikson, U; Digre, H; Skavhaug, A; Mathiassen, J R

    2008-03-01

    The present study describes the possibilities for using computer vision-based methods for the detection and monitoring of transient 2D and 3D changes in the geometry of a given product. The rigor contractions of unstressed and stressed fillets of Atlantic salmon (Salmo salar) and Atlantic cod (Gadus morhua) were used as a model system. Gradual changes in fillet shape and size (area, length, width, and roundness) were recorded for 7 and 3 d, respectively. Also, changes in fillet area and height (cross-section profiles) were tracked using a laser beam and a 3D digital camera. Another goal was to compare rigor developments of the 2 species of farmed fish, and whether perimortem stress affected the appearance of the fillets. Some significant changes in fillet size and shape were found (length, width, area, roundness, height) between unstressed and stressed fish during the course of rigor mortis as well as after ice storage (postrigor). However, the observed irreversible stress-related changes were small and would hardly mean anything for postrigor fish processors or consumers. The cod were less stressed (as defined by muscle biochemistry) than the salmon after the 2 species had been subjected to similar stress bouts. Consequently, the difference between the rigor courses of unstressed and stressed fish was more extreme in the case of salmon. However, the maximal whole fish rigor strength was judged to be about the same for both species. Moreover, the reductions in fillet area and length, as well as the increases in width, were basically of similar magnitude for both species. In fact, the increases in fillet roundness and cross-section height were larger for the cod. We conclude that the computer vision method can be used effectively for automated monitoring of changes in 2D and 3D shape and size of fish fillets during rigor mortis and ice storage. In addition, it can be used for grading of fillets according to uniformity in size and shape, as well as measurement of

  18. Characterization of the fatty acyl elongase (elovl) gene family, and hepatic elovl and delta-6 fatty acyl desaturase transcript expression and fatty acid responses to diets containing camelina oil in Atlantic cod (Gadus morhua).

    PubMed

    Xue, Xi; Feng, Charles Y; Hixson, Stefanie M; Johnstone, Kim; Anderson, Derek M; Parrish, Christopher C; Rise, Matthew L

    2014-09-01

    For aquaculture to become sustainable, there is a need to substitute fish oil [FO, rich in ω3 long chain polyunsaturated fatty acids (LC-PUFA) such as 20:5ω3 (EPA) and 22:6ω3 (DHA)] in aquafeed with plant oils such as camelina oil [CO, rich in C18 PUFA such as 18:3ω3 (ALA) and 18:2ω6 (LNA)]. The LC-PUFA are essential components in fish diets for maintaining optimal health, physiology and growth. However, most marine fish including Atlantic cod are inefficient at producing LC-PUFA from shorter chain precursors. Since elovl genes encode enzymes that play key roles in fatty acid biosynthesis, we hypothesized that they may be involved in Atlantic cod responses to diets rich in 18:3ω3 and 18:2ω6. Ten members of the cod elovl gene family were characterized at the mRNA level. RT-PCR was used to study constitutive expression of elovl transcripts in fifteen tissues. Some transcripts (e.g. elovl5) were ubiquitously expressed, while others had tissue-specific expression (e.g. elovl4a in brain and eye). Cod fed a CO-containing diet (100% CO replacement of FO and including solvent-extracted fish meal) had significantly lower weight gain, with significant up-regulation of elovl5 and fadsd6 transcripts in the liver as shown by QPCR analysis, compared with cod on a FO control diet after a 13-week trial. Multivariate statistical analyses (SIMPER and PCA) indicated that high 18:3ω3 and/or low ω3 LC-PUFA levels in the liver were associated with the up-regulation of elovl5 and fadsd6, which are involved in LC-PUFA biosynthesis in cod.

  19. Discovery of miRNAs and Their Corresponding miRNA Genes in Atlantic Cod (Gadus morhua): Use of Stable miRNAs as Reference Genes Reveals Subgroups of miRNAs That Are Highly Expressed in Particular Organs.

    PubMed

    Andreassen, Rune; Rangnes, Fredrik; Sivertsen, Maria; Chiang, Michelle; Tran, Michelle; Worren, Merete Molton

    2016-01-01

    Atlantic cod (Gadus morhua) is among the economically most important species in the northern Atlantic Ocean and a model species for studying development of the immune system in vertebrates. MicroRNAs (miRNAs) are an abundant class of small RNA molecules that regulate fundamental biological processes at the post-transcriptional level. Detailed knowledge about a species miRNA repertoire is necessary to study how the miRNA transcriptome modulate gene expression. We have therefore discovered and characterized mature miRNAs and their corresponding miRNA genes in Atlantic cod. We have also performed a validation study to identify suitable reference genes for RT-qPCR analysis of miRNA expression in Atlantic cod. Finally, we utilized the newly characterized miRNA repertoire and the dedicated RT-qPCR method to reveal miRNAs that are highly expressed in certain organs. The discovery analysis revealed 490 mature miRNAs (401 unique sequences) along with precursor sequences and genomic location of the miRNA genes. Twenty six of these were novel miRNA genes. Validation studies ranked gmo-miR-17-1-5p or the two-gene combination gmo-miR25-3p and gmo-miR210-5p as most suitable qPCR reference genes. Analysis by RT-qPCR revealed 45 miRNAs with significantly higher expression in tissues from one or a few organs. Comparisons to other vertebrates indicate that some of these miRNAs may regulate processes like growth, lipid metabolism, immune response to microbial infections and scar damage repair. Three teleost-specific and three novel Atlantic cod miRNAs were among the differentially expressed miRNAs. The number of known mature miRNAs was considerably increased by our identification of miRNAs and miRNA genes in Atlantic cod. This will benefit further functional studies of miRNA expression using deep sequencing methods. The validation study showed that stable miRNAs are suitable reference genes for RT-qPCR analysis of miRNA expression. Applying RT-qPCR we have identified several mi

  20. Discovery of miRNAs and Their Corresponding miRNA Genes in Atlantic Cod (Gadus morhua): Use of Stable miRNAs as Reference Genes Reveals Subgroups of miRNAs That Are Highly Expressed in Particular Organs

    PubMed Central

    Andreassen, Rune; Rangnes, Fredrik; Sivertsen, Maria; Chiang, Michelle; Tran, Michelle; Worren, Merete Molton

    2016-01-01

    Background Atlantic cod (Gadus morhua) is among the economically most important species in the northern Atlantic Ocean and a model species for studying development of the immune system in vertebrates. MicroRNAs (miRNAs) are an abundant class of small RNA molecules that regulate fundamental biological processes at the post-transcriptional level. Detailed knowledge about a species miRNA repertoire is necessary to study how the miRNA transcriptome modulate gene expression. We have therefore discovered and characterized mature miRNAs and their corresponding miRNA genes in Atlantic cod. We have also performed a validation study to identify suitable reference genes for RT-qPCR analysis of miRNA expression in Atlantic cod. Finally, we utilized the newly characterized miRNA repertoire and the dedicated RT-qPCR method to reveal miRNAs that are highly expressed in certain organs. Results The discovery analysis revealed 490 mature miRNAs (401 unique sequences) along with precursor sequences and genomic location of the miRNA genes. Twenty six of these were novel miRNA genes. Validation studies ranked gmo-miR-17-1—5p or the two-gene combination gmo-miR25-3p and gmo-miR210-5p as most suitable qPCR reference genes. Analysis by RT-qPCR revealed 45 miRNAs with significantly higher expression in tissues from one or a few organs. Comparisons to other vertebrates indicate that some of these miRNAs may regulate processes like growth, lipid metabolism, immune response to microbial infections and scar damage repair. Three teleost-specific and three novel Atlantic cod miRNAs were among the differentially expressed miRNAs. Conclusions The number of known mature miRNAs was considerably increased by our identification of miRNAs and miRNA genes in Atlantic cod. This will benefit further functional studies of miRNA expression using deep sequencing methods. The validation study showed that stable miRNAs are suitable reference genes for RT-qPCR analysis of miRNA expression. Applying RT-qPCR we

  1. Effects of 17alpha-methyltestosterone exposure on steroidogenesis and cyclin-B mRNA expression in previtellogenic oocytes of Atlantic cod (Gadus morhua).

    PubMed

    Kortner, Trond M; Arukwe, Augustine

    2007-11-01

    Steroid hormone (estrogens and androgens) synthesis and regulation involve a large number of enzymes and potential biochemical pathways. In the context of these biochemical pathways, it is believed that the true rate-limiting step in acute steroid production is the movement of cholesterol across the mitochondrial membrane by the steroidogenic acute regulatory (StAR) protein and the subsequent conversion to pregnenolone by cytochrome P450-mediated side-chain cleavage (P450scc) enzyme. Oocyte development is a complex process that is triggered by the maturation-promoting factor (MPF) involving cyclin-B as a regulatory factor. In the present study, we evaluated the endocrine effects of 17alpha-methyltestosterone (MT) on steroidogenic pathways of Atlantic cod (Gadus morhua), using an in vitro previtellogenic oocyte culture technique that is based on an agarose floating method. Tissue was cultured in a humidified incubator at 10 degrees C for 1, 5, 10 and 20 days with different concentrations of the synthetic androgen MT (0 (control), 1, 10, 100 and 1000 microM) dissolved in ethanol (0.3%). Gene expressions for StAR, P450scc, aromatase-alpha (P450aromA) and cyclin-B were detected using validated real-time PCR with specific primer pairs. Cellular localization of the StAR protein and P450scc were performed using the immunohistochemical technique with antisera prepared against synthetic peptide for both proteins. Steroid hormones (estradiol-17beta: E2 and testosterone: T) levels were estimated using enzyme immunoassay. Our data showed significant concentration-specific increase (at day 1 and 5) and decrease (at day 10 and 20) of the StAR mRNA expression after exposure to MT. P450scc expression showed a MT concentration-specific decrease during the exposure periods and cyclin-B mRNA expression was decreased in MT concentration-dependent manner at days 10 and 20 (reaching almost total inhibition after exposure to 1000 microM MT). MT exposure produced variable effects on the P

  2. Substitution of fish oil with camelina oil and inclusion of camelina meal in diets fed to Atlantic cod (Gadus morhua) and their effects on growth, tissue lipid classes, and fatty acids.

    PubMed

    Hixson, S M; Parrish, C C

    2014-03-01

    Developing a commercially relevant Atlantic cod aquaculture industry will require improvements in feed sustainability. Camelina oil and meal are potential replacements of fish oil and fish meal in aquaculture feeds. Camelina oil is high in 18:3ω3 (30%), with an ω3/ω6 ratio > 1. Camelina meal has a considerable crude protein level (38%), which includes significant amounts of methionine and phenylalanine. Four diets were tested; each diet was fed to triplicate tanks (3 tanks per diet) of Atlantic cod (14.4 g/fish; 70 fish per tank) for 13 wk. The diets included a fish oil/fish meal control (FO) and three diets which replaced 100% of fish oil with camelina oil: one diet contained fish meal (100CO), another solvent extracted fish meal (100COSEFM), and another had fish meal partially reduced by 15% inclusion of camelina meal (100CO15CM). Growth was measured (length and weight) and tissue samples were collected for lipid analysis (muscle, liver, brain, gut, spleen, skin, and carcass) at wk 0 (before feeding the experimental diet) and at wk 13. Cod fed camelina oil had a lower (P < 0.001) final weight than cod fed the FO diet (50.8 ± 10.3 g/fish). Cod fed 100CO15CM had a lower (P < 0.001) final weight (35.0 ± 8.0 g) than those fed 100CO (43.6 ± 8.9 g) and 100COSEFM (46.7 ± 10.7 g). Cod tissues in the 100COSEFM treatment were most impacted by dietary fatty acid profile. Multivariate statistics revealed that FO and 100COSEFM tissue fatty acid profiles were 21 to 31% different, depending on tissue type. The full replacement of fish oil with camelina oil, plus solvent extracted fish meal had an overarching effect on the entire fatty acid profile of the whole animal. Fatty acid mass balance calculations indicated that cod fed 100COSEFM elongated 13% of 18:3ω3 to 20:3ω3 and oxidized the remaining 87%, whereas cod fed fish oil showed a much lower (P < 0.001) elongation of 18:3ω3 of 1.6%. These results suggest that excess 18:3ω3 from camelina oil caused some fatty acid

  3. Process control of lightly salted wild and farmed Atlantic cod (Gadus morhua) by brine injection, brining, and freezing--a low field NMR study.

    PubMed

    Gudjonsdottir, Maria; Gunnlaugsson, Valur N; Finnbogadottir, Gudrun A; Sveinsdottir, Kolbrun; Magnusson, Hannes; Arason, Sigurjon; Rustad, Turid

    2010-10-01

    The aim of this study was to use low-field nuclear magnetic resonance (NMR) and traditional chemical methods to investigate the physical and chemical differences in wild and farmed cod processed pre- and postrigor, and how these properties were affected by brine injection, brining, and freezing. In prerigor processed farmed or wild cod, brine injections followed by brining for 2 d, with brine concentrations up to 5.5% and 4%, respectively, were not sufficient to reach a muscle salt concentration of 2% as aimed for, while wild cod processed postrigor had sufficient salt uptake after the same processing. Low-field NMR gave valuable information about the differences in the muscle structure between wild and farmed cod as well as the state of the water in the muscle during brine injection, brining, and during rigor tension. Low-field NMR is, therefore, a valuable tool that can be used to optimize the salting and storing processes of lightly salted cod products from both wild and farmed cod. For farmed cod to be used in the production of lightly salted products further research is needed. Practical Application: Optimal processing of lightly salted cod products is important to the fish industry, due to an increasing market for this product in southern Europe. Farmed cod, which is seen as a potential steady raw material source for this production, differs considerably from its wild counterparts by having other chemical and physical muscle properties, such as lower water content and lower pH. With the processing procedures used today the farmed cod can, therefore, only be used in some of the products, where wild cod is currently used as raw material. It is, therefore, important that the processing of these products is optimized with regard to these differences in the raw material. This study gives a valuable contribution to further studies about optimal combinations of brine injections, brining, and freezing of pre- and postrigor processed farmed compared to wild cod.

  4. Impact of long-term moderate hypercapnia and elevated temperature on the energy budget of isolated gills of Atlantic cod (Gadus morhua).

    PubMed

    Kreiss, Cornelia M; Michael, Katharina; Bock, Christian; Lucassen, Magnus; Pörtner, Hans-O

    2015-04-01

    Effects of severe hypercapnia have been extensively studied in marine fishes, while knowledge on the impacts of moderately elevated CO2 levels and their combination with warming is scarce. Here we investigate ion regulation mechanisms and energy budget in gills from Atlantic cod acclimated long-term to elevated PCO2 levels (2500 μatm) and temperature (18°C). Isolated perfused gill preparations were established to determine gill thermal plasticity during acute exposures (10-22°C) and in vivo costs of Na(+)/K(+)-ATPase activity, protein and RNA synthesis. Maximum enzyme capacities of F1Fo-ATPase, H(+)-ATPase and Na(+)/K(+)-ATPase were measured in vitro in crude gill homogenates. After whole animal acclimation to elevated PCO2 and/or warming, branchial oxygen consumption responded more strongly to acute temperature change. The fractions of gill respiration allocated to protein and RNA synthesis remained unchanged. In gills of fish CO2-exposed at both temperatures, energy turnover associated with Na(+)/K(+)-ATPase activity was reduced by 30% below rates of control fish. This contrasted in vitro capacities of Na(+)/K(+)-ATPase, which remained unchanged under elevated CO2 at 10°C, and earlier studies which had found a strong upregulation under severe hypercapnia. F1Fo-ATPase capacities increased in hypercapnic gills at both temperatures, whereas Na(+)/K(+)ATPase and H(+)-ATPase capacities only increased in response to elevated CO2 and warming indicating the absence of thermal compensation under CO2. We conclude that in vivo ion regulatory energy demand is lowered under moderately elevated CO2 levels despite the stronger thermal response of total gill respiration and the upregulation of F1Fo-ATPase. This effect is maintained at elevated temperature. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. High rates of glucose utilization in the gas gland of Atlantic cod (Gadus morhua) are supported by GLUT1 and HK1b.

    PubMed

    Clow, Kathy A; Short, Connie E; Hall, Jennifer R; Gendron, Robert L; Paradis, Hélène; Ralhan, Ankur; Driedzic, William R

    2016-09-01

    The gas gland of physoclistous fish utilizes glucose to generate lactic acid that leads to the off-loading of oxygen from haemoglobin. This study addresses characteristics of the first two steps in glucose utilization in the gas gland of Atlantic cod (Gadus morhua). Glucose metabolism by isolated gas gland cells was 12- and 170-fold higher, respectively, than that in heart and red blood cells (RBCs) as determined by the production of (3)H2O from [2-(3)H]glucose. In the gas gland, essentially all of the glucose consumed was converted to lactate. Glucose uptake in the gas gland shows a very high dependence upon facilitated transport as evidenced by saturation of uptake of 2-deoxyglucose at a low extracellular concentration and a requirement for high levels of cytochalasin B for uptake inhibition despite the high efficacy of this treatment in heart and RBCs. Glucose transport is via glucose transporter 1 (GLUT1), which is localized to the glandular cells. GLUT1 western blot analysis from whole-tissue lysates displayed a band with a relative molecular mass of 52 kDa, consistent with the deduced amino acid sequence. Levels of 52 kDa GLUT1 in the gas gland were 2.3- and 33-fold higher, respectively, than those in heart and RBCs, respectively. Glucose phosphorylation is catalysed by hexokinase Ib (HKIb), a paralogue that cannot bind to the outer mitochondrial membrane. Transcript levels of HKIb in the gas gland were 52- and 57-fold more abundant, respectively, than those in heart and RBCs. It appears that high levels of GLUT1 protein and an unusual isoform of HKI are both critical for the high rates of glycolysis in gas gland cells. © 2016. Published by The Company of Biologists Ltd.

  6. Effects of elevated dissolved carbon dioxide and perfluorooctane sulfonic acid, given singly and in combination, on steroidogenic and biotransformation pathways of Atlantic cod.

    PubMed

    Preus-Olsen, Gunnhild; Olufsen, Marianne O; Pedersen, Sindre Andre; Letcher, Robert J; Arukwe, Augustine

    2014-10-01

    In the aquatic environments, the predicted changes in water temperature, pO2 and pCO2 could result in hypercapnic and hypoxic conditions for aquatic animals. These conditions are thought to affect several basic cellular and physiological mechanisms. Yet, possible adverse effects of elevated CO2 (hypercapnia) on teleost fish, as well as combined effects with emerging and legacy environmental contaminants are poorly investigated. In this study, juvenile Atlantic cod (Gadus morhua) were divided into groups and exposed to three different water bath PFOS exposure regimes (0 (control), 100 and 200 μg L(-1)) for 5 days at 1h/day, followed by three different CO2-levels (normocapnia, moderate (0.3%) and high (0.9%)). The moderate CO2 level is the predicted near future (within year 2300) level, while 0.9% represent severe hypercapnia. Tissue samples were collected at 3, 6 and 9 days after initiated CO2 exposure. Effects on the endocrine and biotransformation systems were examined by analyzing levels of sex steroid hormones (E2, T, 11-KT) and transcript expression of estrogen responsive genes (ERα, Vtg-α, Vtg-β, ZP2 and ZP3). In addition, transcripts for genes encoding xenobiotic metabolizing enzymes (cyp1a and cyp3a) and hypoxia-inducible factor (HIF-1α) were analyzed. Hypercapnia alone produced increased levels of sex steroid hormones (E2, T, 11-KT) with concomitant mRNA level increase of estrogen responsive genes, while PFOS produced weak and time-dependent effects on E2-inducible gene transcription. Combined PFOS and hypercapnia exposure produced increased effects on sex steroid levels as compared to hypercapnia alone, with transcript expression patterns that are indicative of time-dependent interactive effects. Exposure to hypercapnia singly or in combination with PFOS produced modulations of the biotransformation and hypoxic responses that were apparently concentration- and time-dependent. Loading plots of principal component analysis (PCA) produced a significant

  7. Seasonal and annual variation in the diet of Atlantic cod (Gadus morhua) in relation to the abundance of capelin (Mallotus villosus) off eastern Newfoundland, Canada

    USGS Publications Warehouse

    Methven, David A.; Piatt, John F.

    1989-01-01

    The importance of capelin as prey for cod has long been known (Thompson, 1943; and see Lilly (1987) for a review); however, no studies have been conducted on how the highly dynamic seasonal and yearly variations in capelin abundance affect cod diet. We studied the occurrence of capelin in cod stomachs in relation to the relative abundance of capelin at Witless Bay, Newfoundland (47°15’N 52°46’W), during June, July and August, 1982-1984. The mean number of capelin per stomach and the per cent occurrence of stomachs containing capelin were determined for each collection of stomachs. A total of 680 stomachs were examined. Cod were sampled from those caught in gillnets by fishermen and averaged 66 cm ± 8 (s.d.) in 1983 and 62 cm ± 8 (s.d.) in 1984. Relative abundance of capelin in the local habitat was determined by conducting hydroacoustic surveys around Gull Island in Witless Bay, the same area where cod were collected for stomach content analysis. Only hydroacoustic surveys conducted within three days of cod stomach collections were analyzed. Further details of hydroacoustic surveys including quantifications of acoustic echograms are described in Piatt (1989).

  8. Evaluation of the impact of camelina oil-containing diets on the expression of genes involved in the innate anti-viral immune response in Atlantic cod (Gadus morhua).

    PubMed

    Booman, Marije; Xu, Qingheng; Rise, Matthew L

    2014-11-01

    To improve sustainability of aquaculture, especially for carnivorous species like Atlantic cod, replacement of fish oil-based diets with vegetable oil-based diets has been studied. The use of vegetable oil in fish feeds can significantly change the fatty acid composition of fish tissues, and given the importance of fatty acids in inflammation and immunity, this change could potentially impact the immune response and health of the fish. The oilseed Camelina sativa is a promising source for this vegetable oil, because of the high oil content of its seeds (40%), a higher n-3 fatty acid content than most other oilseeds, and a high amount of γ-tocopherol. This study aims to investigate the effect of the replacement of dietary fish oil with oil from Camelina sativa on the immune response of Atlantic cod, as measured by the gene expression in spleen. Juvenile cod were fed on a fish oil-based diet (FO) or one of two diets in which camelina oil replaced 40% or 80% of fish oil (40CO and 80CO respectively) for 67 days, after which they were injected with either the viral mimic polyriboinosinic polyribocytidylic acid (pIC), or phosphate-buffered saline (PBS) as a control. Microarray analysis was used to determine the effect of the diet on the basal spleen transcriptome (pre-injection), and on the response to pIC (24 h post-injection). No marked differences in the spleen transcriptome were found between the three diets, either before or after injection with pIC. All fish, regardless of diet, showed a strong anti-viral response 24 h after pIC injection, with more than 500 genes having a significant difference of expression of 2-fold or higher compared to the PBS-injected fish for the FO, 40CO and 80CO diets. Gene Ontology annotation analysis of the three pIC-responsive gene lists indicated they were highly similar, and that the term 'immune system process' was significantly enriched in the pIC-responsive gene lists for all three diets. QPCR analysis for 5 genes with a known

  9. β-naphthoflavone interferes with cyp1c1, cox2 and IL-8 gene transcription and leukotriene B4 secretion in Atlantic cod (Gadus morhua) head kidney cells during inflammation.

    PubMed

    Holen, Elisabeth; Olsvik, Pål A

    2016-07-01

    The objective of this study was to evaluate how β-naphthoflavone interacts with lipopolysaccharide (LPS) and polyinosinic acid: polycytidylic acid (poly I: C) induced innate immune parameters as well as phase I and phase II detoxification enzymes in head kidney cells isolated from Atlantic cod. β-naphthoflavone is a pure agonist of aryl hydrocarbon receptor (AhR) while LPS and poly I: C are not. β-naphthoflavone was added to head kidney leukocytes alone or together with LPS or poly I: C and the responses were evaluated in terms of protein and gene expression. The results showed that β-naphthoflavone (25 nM), with and without LPS, significantly induced cytochrome P450 (cyp1c) transcription in cod head kidney cells. β-naphthoflavone (100 nM) in the presence of the virus mimic, poly I: C, also increased cyp1c1transcription. LPS induced cyp1c1, cyclooxygenase 2 (cox2), interleukin 1β (IL-1β), interleukin 6 (IL-6) and interleukin 8 (IL-8) transcription, genes that were not affected by the tested β-naphthoflavone concentrations alone. However, β-naphthoflavone (25 and 50 nM) strengthened LPS induced cox2 and IL-8 transcription. Cod head kidney cells exposed to β-naphthoflavone concentrations ranging from 25 to 100 nM, with and without LPS or poly I: C, expressed AhR protein. LPS or β-naphthoflavone (5-50 nM) significantly induced leukotriene B4 (LTB4) secretion compared to control. In conclusion, this study suggests that β-naphthoflavone could interfere with LPS induced immune cell signaling in cod head kidney cells.

  10. Heat-shock responsive genes identified and validated in Atlantic cod (Gadus morhua) liver, head kidney and skeletal muscle using genomic techniques

    PubMed Central

    2010-01-01

    Background Daily and seasonal changes in temperature are challenges that fish within aquaculture settings cannot completely avoid, and are known to elicit complex organismal and cellular stress responses. We conducted a large-scale gene discovery and transcript expression study in order to better understand the genes that are potentially involved in the physiological and cellular aspects of stress caused by heat-shock. We used suppression subtractive hybridization (SSH) cDNA library construction and characterization to identify transcripts that were dysregulated by heat-shock in liver, skeletal muscle and head kidney of Atlantic cod. These tissues were selected due to their roles in metabolic regulation, locomotion and growth, and immune function, respectively. Fish were exposed for 3 hours to an 8°C elevation in temperature, and then allowed to recover for 24 hours at the original temperature (i.e. 10°C). Tissue samples obtained before heat-shock (BHS), at the cessation of heat-shock (CS), and 3, 12, and 24 hours after the cessation of heat-shock (ACS), were used for reciprocal SSH library construction and quantitative reverse transcription - polymerase chain reaction (QPCR) analysis of gene expression using samples from a group that was transferred but not heat-shocked (CT) as controls. Results We sequenced and characterized 4394 ESTs (1524 from liver, 1451 from head kidney and 1419 from skeletal muscle) from three "forward subtracted" libraries (enriched for genes up-regulated by heat-shock) and 1586 from the liver "reverse subtracted" library (enriched for genes down-regulated by heat-shock), for a total of 5980 ESTs. Several cDNAs encoding putative chaperones belonging to the heat-shock protein (HSP) family were found in these libraries, and "protein folding" was among the gene ontology (GO) terms with the highest proportion in the libraries. QPCR analysis of HSP90α and HSP70-1 (synonym: HSPA1A) mRNA expression showed significant up-regulation in all three

  11. The role of extracellular matrix components in pin bone attachments during storage-a comparison between farmed Atlantic salmon (Salmo salar) and cod (Gadus morhua L.).

    PubMed

    Rønning, Sissel B; Østbye, Tone-Kari; Krasnov, Aleksei; Vuong, Tram T; Veiseth-Kent, Eva; Kolset, Svein O; Pedersen, Mona E

    2017-04-01

    Pin bones represent a major problem for processing and quality of fish products. Development of methods of removal requires better knowledge of the pin bones' attachment to the muscle and structures involved in the breakdown during loosening. In this study, pin bones from cod and salmon were dissected from fish fillets after slaughter or storage on ice for 5 days, and thereafter analysed with molecular methods, which revealed major differences between these species before and after storage. The connective tissue (CT) attaches the pin bone to the muscle in cod, while the pin bones in salmon are embedded in adipose tissue. Collagens, elastin, lectin-binding proteins and glycosaminoglycans (GAGs) are all components of the attachment site, and this differ between salmon and cod, resulting in a CT in cod that is more resistant to enzymatic degradation compared to the CT in salmon. Structural differences are reflected in the composition of transcriptome. Microarray analysis comparing the attachment sites of the pin bones with a reference muscle sample showed limited differences in salmon. In cod, on the other hand, the variances were substantial, and the gene expression profiles suggested difference in myofibre structure, metabolism and cell processes between the pin bone attachment site and the reference muscle. Degradation of the connective tissue occurs closest to the pin bones and not in the neighbouring tissue, which was shown using light microscopy. This study shows that the attachment of the pin bones in cod and salmon is different; therefore, the development of methods for removal should be tailored to each individual species.

  12. ¹H, ¹³C and ¹⁵N resonance assignments and second structure information of Gad m 1: a β-parvalbumin allergen from Atlantic cod (Gadus morhua).

    PubMed

    Moraes, A H; Ackerbauer, D; Kostadinova, M; Bublin, M; Ferreira, F; Almeida, F C L; Breiteneder, H; Valente, A P

    2013-10-01

    Gad m 1 is the major allergen from Atlantic cod. It belongs to β-parvalbumin protein family and is characterized by the presence of two calcium-binding sites so called EF-hand motifs. β-Parvalbumins such as Gad m 1 are the most important fish allergens and their high cross-reactivity is the cause of the observed polysensitization to various fish species in allergic patients. Despite extensive efforts, the complete elucidation of β-parvalbumin-IgE complexes has not been achieved yet. Allergen structural studies are essential for the development of novel immunotherapy strategies, including vaccination with hypoallergenic derivatives and chimeric molecules. Here, we report for the first time the NMR study of a β-parvalbumin: Gad m 1. This report includes: (1)H, (13)C and (15)N resonance assignments of Gad m 1 as well as the second structure information based on the (13)C chemical shifts.

  13. Environmental genotoxicity and cytotoxicity in flounder (Platichthys flesus), herring (Clupea harengus) and Atlantic cod (Gadus morhua) from chemical munitions dumping zones in the southern Baltic Sea.

    PubMed

    Baršienė, Janina; Butrimavičienė, Laura; Grygiel, Wlodzimierz; Lang, Thomas; Michailovas, Aleksandras; Jackūnas, Tomas

    2014-05-01

    The data on environmental genotoxicity and cytotoxicity levels as well as on genotoxicity risk in flounder (Platichthys flesus), herring (Clupea harengus) and cod (Gadus morhua) collected in 2010-2012 at 42 stations located in chemical munitions dumping areas of the southern Baltic Sea are presented. The frequency of micronuclei, nuclear buds and nucleoplasmic bridges in erythrocytes was used as genotoxicity endpoint and the induction of fragmented-apoptotic, bi-nucleated and 8-shaped erythrocytes as cytotoxicity endpoint. The most significantly increased geno-cytotoxicity levels were determined in fish collected near known chemical munitions dumpsites. Extremely high genotoxicity risk for flounder were identified at 21 out of 24 stations, for herring at 29 out of 31 and for cod at 5 out of 10 stations studied. The reference level of genotoxicity was not recorded at any of the stations revealing that in the sampling area fish were affected generally.

  14. Response of branchial Na(+)/K(+) ATPase to changes in ambient temperature in Atlantic cod (Gadus morhua) and whiting (Merlangius merlangus).

    PubMed

    Michael, Katharina; Koschnick, Nils; Pörtner, Hans-O; Lucassen, Magnus

    2016-05-01

    The maintenance of ion and pH homeostasis despite changes in ambient temperature is crucial for ectothermic organisms. Thermal sensitivity of Na(+)/K(+) ATPase mRNA expression, protein expression and activity was determined in gills of North Sea cod (NC) and Northeastern Arctic cod (NEAC), acclimated for 6 weeks at 4 and 10 °C and compared to field samples of North Sea cod (sNC), acclimatized to early spring (4 °C) and summer (18 °C) conditions. The same analyses were conducted in gills of the confamiliar whiting, acclimated at 4 and 10 °C. Branchial Na(+)/K(+) ATPase capacities remained uncompensated at functional and protein levels in NC and NEAC at both acclimation temperatures. Na(+)/K(+) ATPase mRNA expression in NEAC acclimated at 10 °C was about twofold higher compared to NC, indicating some population-specific differentiation at this level. Lower Na(+)/K(+) ATPase capacities in gills of warm-acclimatized sNC at common assay temperatures indicate thermal compensation between seasonal extremes, and post-translational modifications contributed to this mitigation at high assay temperature. Together, cod compensates Na(+)/K(+) ATPase capacities on the warm edge of the thermal window and below 4 °C, respectively. In contrast, whiting Na(+)/K(+) ATPase capacities were cold compensated at 4 °C, supported by 1.5-fold higher mRNA and protein expression. Besides, capacities were lower in whiting compared to NC and NEAC at optimum temperature, which may be advantageous in terms of reduced maintenance cost, but at temperatures ≤4 °C, compensation may represent an energy trade-off to maintain homeostasis. The species-specific response of gadid Na(+)/K(+) ATPase indicates certain threshold temperatures beyond which compensation of the pump is elicited, possibly related to the different biogeography of these species.

  15. Sex dimorphic expression of five dmrt genes identified in the Atlantic cod genome. The fish-specific dmrt2b diverged from dmrt2a before the fish whole-genome duplication.

    PubMed

    Johnsen, Hanne; Andersen, Øivind

    2012-09-01

    The Doublesex and Mab-3 related transcription factors (Dmrt) are characterised by the zinc finger-like DM domain binding similar DNA sequences, but show different spatio-temporal expression patterns and functions throughout ontogenesis. Dmrt1 is the master regulator of sex determination in very distant metazoans, while Dmrt2 and Dmrt4 are of crucial importance in vertebrate somitogenesis and neurogenesis, respectively. To elucidate the evolutionary divergence of the fish dmrt genes, we examined the expression patterns and the chromosomal synteny of the five dmrt genes identified in the Atlantic cod genome. Quantitative PCR analyses of cod dmrt1, dmrt2a, dmrt3, dmrt4 and dmrt5 revealed distinct expression patterns in the embryo and larvae, and indicated conserved extragonadal functions during early development. Several dmrt genes seem to be involved in the sexual differentiation of gonads and brain, but the sex-dimorphic expression patterns differed substantially between teleosts, suggesting functional switch between Dmrt members. The dmrt2a-dmrt3-dmrt1 cluster was found to be located in a conserved syntenic region, and the flanking genes have become duplicated in teleosts and are closely linked in a paralogous region lacking the dmrt cluster. Similarly, the region containing the fish-specific dmrt2b gene was found to have a paralogous region without a dmrt2b duplicate in a separate linkage group in the teleost genomes. We propose that the teleost segments paralogous to the dmrt2a- and dmrt2b regions, respectively, were formed through the fish-specific whole genome duplication (3R), while dmrt2a and dmrt2b originated from the second round (2R) of whole genome duplication of the ancestral dmrt2. The dmrt2b paralog seems to have been lost in Atlantic cod as in tetrapods and may be a pseudogene in pufferfish, while dmrt2a and dmrt2b have acquired different functions in zebrafish. Contrasting with the retained duplicates of dmrt flanking genes, the massive losses of

  16. Climate induced temperature effects on growth performance, fecundity and recruitment in marine fish: developing a hypothesis for cause and effect relationships in Atlantic cod ( Gadus morhua) and common eelpout ( Zoarces viviparus)

    NASA Astrophysics Data System (ADS)

    Pörtner, H. O.; Berdal, B.; Blust, R.; Brix, O.; Colosimo, A.; De Wachter, B.; Giuliani, A.; Johansen, T.; Fischer, T.; Knust, R.; Lannig, G.; Naevdal, G.; Nedenes, A.; Nyhammer, G.; Sartoris, F. J.; Serendero, I.; Sirabella, P.; Thorkildsen, S.; Zakhartsev, M.

    2001-12-01

    Effects of global warming on animal distribution and performance become visible in many marine ecosystems. The present study was designed to develop a concept for a cause and effect understanding with respect to temperature changes and to explain ecological findings based on physiological processes. The concept is based on a wide comparison of invertebrate and fish species with a special focus on recent data obtained in two model species of fish. These fish species are both characterized by northern and southern distribution limits in the North Atlantic: eelpout ( Zoarces viviparus), as a typical non-migrating inhabitant of the coastal zone and the cod ( Gadus morhua), as a typical inhabitant of the continental shelf with a high importance for fisheries. Mathematical modelling demonstrates a clear significant correlation between climate induced temperature fluctuations and the recruitment of cod stocks. Growth performance in cod is optimal at temperatures close to 10°C, regardless of the population investigated in a latitudinal cline. However, temperature specific growth rates decrease at higher latitudes. Also, fecundity is less in White Sea than in North and Baltic Sea cod or eelpout populations. These findings suggest that a cold-induced shift in energy budget occurs which is unfavorable for growth performance and fecundity. Thermal tolerance limits shift depending on latitude and are characterized by oxygen limitation at both low or high temperatures. Oxygen supply to tissues is optimized at low temperature by a shift in hemoglobin isoforms and oxygen binding properties to lower affinities and higher unloading potential. Protective stimulation of heat shock protein synthesis was not observed. According to a recent model of thermal tolerance the downward shift of tolerance limits during cold adaptation is associated with rising mitochondrial densities and, thus, aerobic capacity and performance in the cold, especially in eurythermal species. At the same time

  17. Modeling growth of Atlantic cod larvae on the southern flank of Georges Bank in the tidal-front circulation during May 1999

    NASA Astrophysics Data System (ADS)

    Lough, R. G.; Broughton, E. A.; Buckley, L. J.; Incze, L. S.; Pehrson Edwards, K.; Converse, R.; Aretxabaleta, A.; Werner, F. E.

    2006-11-01

    Cruises were conducted in spring 1999 to describe the interaction between tidal-front processes and the transport, retention, and growth of cod larvae and their prey during the seasonal transition to a stratified water-column along the southern flank of Georges Bank. All the physical and biological observations were integrated in coupled circulation-trophodynamic simulations. The three-dimensional circulation fields were modeled using data assimilation methods described in Aretxabaleta et al. [2005. Data assimilative hindcast on the Southern Flank of Georges Bank during May 1999: frontal circulation and implications. Continental Shelf Research 25, 849-874]. The individual-based model (IBM) of Lough et al. [2005. A general biophysical model of larval cod growth applied to populations on Georges Bank. Fisheries Oceanography 14, 241-262] was used to consider trophodynamic effects on the growth and survival of larval cod. Prey fields were specified for mixed and stratified water columns from field surveys and allowed to adjust in the circulation model. Encounter and ingestion rates of larvae were functions of prey concentration, larval search patterns, light, swimming speeds of predator and prey, and turbulence. Model outputs provide hourly depth-dependent estimates of growth rates, prey biomass ingested, and larval length and weight. Simulations were conducted along a 2-D transect across the tidal front, from mixed to stratified water columns, before and after a wind event. Pre-storm, observed larval cod growth rates, based on RNA-DNA analysis, were highest in the surface 20 m at the stratified and front stations. Post-storm, larval growth rates decreased 1-2% d -1 at the stratified and front stations, corresponding with a <1 °C decrease in temperature. At the mixed station, there was no apparent difference in growth rates with depth, either before or after the storm. Simulations indicate that maximum larval growth rates can occur at the tidal-mixing front due to the

  18. Transcriptome profiling reveals that feeding wild zooplankton to larval Atlantic cod (Gadus morhua) influences suites of genes involved in oxidation-reduction, mitosis, and selenium homeostasis.

    PubMed

    Rise, Matthew L; Hall, Jennifer R; Nash, Gordon W; Xue, Xi; Booman, Marije; Katan, Tomer; Gamperl, A Kurt

    2015-11-26

    Larval nutrition and growth are key issues for wild and cultured cod. While it was shown previously that larval cod fed wild zooplankton grow faster than those fed only rotifers, the mechanisms involved in this enhanced growth are not completely understood. We used microarrays to identify larval cod transcripts that respond to feeding with small amounts of wild zooplankton (5-10 % of live prey items). The larval transcriptome was compared between 3 treatment groups [fed rotifers (RA), rotifers with protein hydrolysate (RA-PH), or rotifers with zooplankton (RA-Zoo)] at 9-10 mm length [26-30 days post-hatch (dph)] to identify a robust suite of zooplankton-responsive genes (i.e. differentially expressed between RA-Zoo and both other groups). The microarray experiment identified 147 significantly up-regulated and 156 significantly down-regulated features in RA-Zoo compared with both RA and RA-PH. Gene ontology terms overrepresented in the RA-Zoo responsive gene set included "response to selenium ion" and several related to cell division and oxidation-reduction. Ten selenoprotein-encoding genes, and 2 genes involved in thyroid hormone generation, were up-regulated in RA-Zoo compared with both other groups. Hierarchical clustering of RA-Zoo responsive genes involved in oxidation-reduction and selenium homeostasis demonstrated that only the zooplankton treatment had a considerable and consistent impact on the expression of these genes. Fourteen microarray-identified genes were selected for QPCR involving 9-13 mm larvae, and 13 of these were validated as differentially expressed between RA-Zoo and both other groups at ~9 mm. In contrast, in age-matched (34-35 dph; ~11 mm RA and RA-PH, ~13 mm RA-Zoo) and size-matched (~13 mm) older larvae, only 2 and 3 genes, respectively, showed the same direction of RA-Zoo-responsive change as in ~9 mm larvae. The modulation of genes involved in selenium binding, redox homeostasis, and thyroid hormone generation in ~9 mm RA-Zoo larvae in

  19. Aryl hydrocarbon receptor protein and Cyp1A1 gene induction by LPS and phenanthrene in Atlantic cod (Gadus morhua) head kidney cells.

    PubMed

    Holen, Elisabeth; Olsvik, Pål Asgeir

    2014-10-01

    The objective of this study was to evaluate interactions between environmental toxicants and cod immune cells during inflammation. Phenanthrene is abundant in plant oils (rapeseed, palm, and soya oil) as compared to fish oils, and consequently constitute an undesirable element in plant replacement diets in aquaculture. Phenanthrene was added to head kidney cell cultures, alone or together with LPS (lipopolysaccharide) or poly I: C (polyinosinic acid: polycytidylic acid), and the responses were evaluated in terms of protein and gene expression. The results showed that LPS, poly I: C or phenanthrene, added to the cultures separately, induced aryl hydrocarbon receptor (AhR) protein expression. Phenanthrene treatment in combination with LPS induced AhR protein expression and Cyp1A1 gene transcription, which not was observed combining poly I: C and phenanthrene. Phenanthrene exposure up regulated the transcription of common stress and detoxification enzymes like catalase, caspase 3 and glutathione S-transferase alfa 3 subunit B (GSTAB3), while LPS exposure alone or combined with phenanthrene down regulated GSTAB3 and catalase in cod leukocytes. It seems clear that immune regulation and phenanthrene induced signaling pathways interact; transcriptional down regulation of detoxification and antioxidant enzymes by LPS could indicate that combating bacterial infections is the number one priority in these cells, and that AhR and Cyp1A1 is somehow involved in this signaling cascade. LPS seems to affect the mitogen activated protein kinases (MAPKs) pathways (P-p38 and ERK1/2) thus modulating the AhR protein and Cyp1A1 gene transcription, while phenanthrene possibly activates AhR by ligand binding.

  20. Transcriptional responses in juvenile Atlantic cod (Gadus morhua) after exposure to mercury-contaminated sediments obtained near the wreck of the German WW2 submarine U-864, and from Bergen Harbor, Western Norway.

    PubMed

    Olsvik, Pål A; Brattås, Marianne; Lie, Kai K; Goksøyr, Anders

    2011-04-01

    The main aim of the present work was to investigate the effects of mercury (Hg)-enriched sediments on fish. Sediments near the sunken German WW2 submarine U-864, which according to historical documents included 67 tons of metallic Hg in its cargo, are enriched of Hg leaking from the wreckage. Juvenile Atlantic cod (Gadus morhua) were exposed to two field-collected polluted sediments (U-864: inorganic Hg and Bergen Harbor (Vågen): inorganic Hg, PCB and PAH) or two comparable reference sediments for 5 weeks in the laboratory, and transcriptional responses evaluated in gills and liver. Gills of fish exposed to the Hg-enriched sunken WW2 submarine U-864 sediment contained four fold higher Hg levels compared to the control fish. An increase in Hg content in liver in the U-864 fish was also observed. The transcriptional results showed that calreticulin, HSP70 and heme oxygenase mRNA were significantly up-regulated in gills in fish exposed to the Hg-enriched sediments, whereas calreticulin, heme oxygenase, transferrin and WAP65 were significantly up-regulated and glutathione peroxidase 4B and zona pellucida 3 were significantly down-regulated in liver tissue. In gills and liver of cod exposed to the mixed-contaminated Vågen sediment, CYP1A showed the highest induction. In conclusion, the experiment shows that sediment-bound Hg is available to the fish and affects the transcription of oxidative stress responsive enzymes, suggesting that the Hg-enriched sediments may negatively affect the local wildlife. Furthermore, the mixed contaminated sediments of Vågen affected similar responses in addition to Ah-receptor mediated responses reflecting exposure to PAHs and PCBs.

  1. Estimating effluent COD

    SciTech Connect

    Eckenfelder, W.W.; Landine, R.

    1995-06-01

    In many parts of the world, chemical oxygen demand (COD) is a primary effluent parameter. Unlike BOD, which considers only biodegradable organics, COD also includes non-degradable organics and non-degradable biological oxidation by-products, generally referred to as soluble microbial products (SMP). The SMP can vary from 2% to 10% of the influent degradable COD. If the technology is limited to biological treatment only, the degradable COD will be removed. Further reductions in COD will require physical chemical treatments such as activated carbon. Effluent COD values for several industrial wastewaters are presented. Effluent characteristics from the anaerobic treatment of industrial wastewaters are also discussed.

  2. Understanding climate impacts on recruitment and spatial dynamics of Atlantic cod in the Gulf of Maine: Integration of observations and modeling

    NASA Astrophysics Data System (ADS)

    Runge, Jeffrey A.; Kovach, Adrienne I.; Churchill, James H.; Kerr, Lisa A.; Morrison, John R.; Beardsley, Robert C.; Berlinsky, David L.; Chen, Changsheng; Cadrin, Steven X.; Davis, Cabell S.; Ford, Kathryn H.; Grabowski, Jonathan H.; Howell, W. Huntting; Ji, Rubao; Jones, Rebecca J.; Pershing, Andrew J.; Record, Nicholas R.; Thomas, Andrew C.; Sherwood, Graham D.; Tallack, Shelly M. L.; Townsend, David W.

    2010-10-01

    We put forward a combined observing and modeling strategy for evaluating effects of environmental forcing on the dynamics of spatially structured cod populations spawning in the western Gulf of Maine. Recent work indicates at least two genetically differentiated complexes in this region: a late spring spawning, coastal population centered in Ipswich Bay, and a population that spawns in winter inshore and on nearshore banks in the Gulf of Maine and off southern New England. The two populations likely differ in trophic interactions and in physiological and behavioral responses to different winter and spring environments. Coupled physical-biological modeling has advanced to the point where within-decade forecasting of environmental conditions for recruitment to each of the two populations is feasible. However, the modeling needs to be supported by hydrographic, primary production and zooplankton data collected by buoys, and by data from remote sensing and fixed station sampling. Forecasts of environmentally driven dispersal and growth of planktonic early life stages, combined with an understanding of possible population-specific predator fields, usage of coastal habitat by juveniles and adult resident and migratory patterns, can be used to develop scenarios for spatially explicit population responses to multiple forcings, including climate change, anthropogenic impacts on nearshore juvenile habitat, connectivity among populations and management interventions such as regional fisheries closures.

  3. Type of carbohydrate in feed affects the expression of small leucine-rich proteoglycans (SLRPs), glycosaminoglycans (GAGs) and interleukins in skeletal muscle of Atlantic cod (Gadus morhua L.).

    PubMed

    Tingbø, M G; Pedersen, M E; Grøndahl, F; Kolset, S O; Veiseth-Kent, E; Enersen, G; Hannesson, K O

    2012-09-01

    Aquaculture requires feed that ensures rapid growth and healthy fish. Higher inclusion of plant ingredients is desirable, as marine resources are limited. In this study we investigated the effects of higher starch inclusion in feed on muscular extracellular matrix and interleukin expression in farmed cod. Starch was replaced by complex fibers in the low-starch diet to keep total carbohydrate inclusion similar. Blood glucose and fructosamine levels were elevated in the high-starch group. The group fed a high-starch diet showed up-regulation on mRNA level of proteoglycans biglycan and decorin. ELISA confirmed the real-time PCR results on protein level for biglycan and also showed increase of lumican. For decorin the protein levels were decreased in the high-starch group, in contrast to real-time PCR results. Disaccharide analyses using HPLC showed reduction of glycosaminoglycans. Further, there was up-regulation of interleukin-1β and -10 on mRNA level in muscle. This study shows that the muscular extracellular matrix composition is affected by diet, and that a high-starch diet results in increased expression of pro-inflammatory genes similar to diabetes in humans. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Cod Liver Oil

    MedlinePlus

    ... cod liver oil on their skin to speed wound healing. When taken in appropriate doses by mouth, cod ... young children. Heart disease. Systemic lupus erythematosus (SLE). Wound healing. Glaucoma. Other conditions. More evidence is needed to ...

  5. The xenoestrogen, 4-nonylphenol, impaired steroidogenesis in previtellogenic oocyte culture of Atlantic cod (Gadus morhua) by targeting the StAR protein and P450scc expressions.

    PubMed

    Kortner, Trond M; Arukwe, Augustine

    2007-02-01

    The steroidogenic acute regulatory (StAR) protein and cytochrome P450-mediated cholesterol side-chain cleavage (P450scc) have been localized in most steroidogenic organs and are rapidly synthesized in response to acute tropic hormone stimulation. In this study, we present the development of cod previtellogenic oocyte in vitro culture system, histological and molecular methods for evaluating the effects of endocrine disruptors such as nonylphenol (NP) on steroid hormone levels, the StAR protein and P450scc. In addition, expression pattern of cyclin-B was studied, because of cyclin B's role as an indicator of oocyte growth in fish. The in vitro previtellogenic oocyte culture technique was based on an agarose floating method. Tissue was cultured in a humidified incubator at 10 degrees C for 4, 7, 14 and 21 d with different concentrations of nonylphenol (0 (control), 1, 10, 50 and 100 microM) dissolved in ethanol (0.3%). Gene expressions were detected using validated real-time polymerase chain reaction (PCR) with specific primers. Immunohistochemistry of the StAR protein and P450scc were performed using antisera prepared against synthetic peptide for both proteins. Estradiol-17beta (E2) and 11-ketotestosterone (11-KT) tissue levels were estimated using enzyme immunoassay. Our data show that nonylphenol produced a unique and consistent concentration-specific pattern of modulation for the StAR protein, P450scc and cyclin-B gene expression at day 14 after exposure. This pattern is generally described as increasing from 0 (control) to 1 and 10 microM, and decreased at 50 and 100 microM. The observed changes in the StAR protein, P450scc and cyclin-B levels showed a direct relationship with changes in 11-KT levels at day 14 after exposure. Cellular localization of StAR and P450scc were specific to the follicular cells of previtellogenic oocytes, but with no differences in staining intensities. No significant change in oocyte diameter was observed between the exposure groups

  6. Cape Cod, Buzzard's Bay, Massachusetts, USA

    NASA Image and Video Library

    1990-03-04

    STS036-151-225 (2 March 1990) --- Surrounded by waters of the Atlantic Ocean, Cape Cod Bay and Nantucket Sound, the jutting Cape Cod feature caught the attention of the astronaut crewmembers aboard the Earth-orbiting Space Shuttle Atlantis, 126 nautical miles above Earth. Parts of Martha's Vineyard and Nantucket are in bottom left corner. Plymouth Bay is in upper left corner. Center point coordinates are 42 degrees north latitude and 70 degrees west longitude. A large format Linhof camera (4" x 5" film) was used to expose the frame.

  7. Plankton effect on cod recruitment in the North Sea

    NASA Astrophysics Data System (ADS)

    Beaugrand, Grégory; Brander, Keith M.; Alistair Lindley, J.; Souissi, Sami; Reid, Philip C.

    2003-12-01

    The Atlantic cod (Gadus morhua L.) has been overexploited in the North Sea since the late 1960s and great concern has been expressed about the decline in cod biomass and recruitment. Here we show that, in addition to the effects of overfishing, fluctuations in plankton have resulted in long-term changes in cod recruitment in the North Sea (bottom-up control). Survival of larval cod is shown to depend on three key biological parameters of their prey: the mean size of prey, seasonal timing and abundance. We suggest a mechanism, involving the match/mismatch hypothesis, by which variability in temperature affects larval cod survival and conclude that rising temperature since the mid-1980s has modified the plankton ecosystem in a way that reduces the survival of young cod.

  8. Plankton effect on cod recruitment in the North Sea.

    PubMed

    Beaugrand, Grégory; Brander, Keith M; Alistair Lindley, J; Souissi, Sami; Reid, Philip C

    2003-12-11

    The Atlantic cod (Gadus morhua L.) has been overexploited in the North Sea since the late 1960s and great concern has been expressed about the decline in cod biomass and recruitment. Here we show that, in addition to the effects of overfishing, fluctuations in plankton have resulted in long-term changes in cod recruitment in the North Sea (bottom-up control). Survival of larval cod is shown to depend on three key biological parameters of their prey: the mean size of prey, seasonal timing and abundance. We suggest a mechanism, involving the match/mismatch hypothesis, by which variability in temperature affects larval cod survival and conclude that rising temperature since the mid-1980s has modified the plankton ecosystem in a way that reduces the survival of young cod.

  9. New England Cod Collapse and the Climate

    PubMed Central

    Meng, Kyle C.; Oremus, Kimberly L.; Gaines, Steven D.

    2016-01-01

    To improve fishery management, there is an increasing need to understand the long-term consequences of natural and anthropogenic climate variability for ecological systems. New England’s iconic cod populations have been in decline for several decades and have recently reached unprecedented lows. We find that 17% of the overall decline in Gulf of Maine cod biomass since 1980 can be attributed to positive phases of the North Atlantic Oscillation (NAO). This is a consequence of three results: i) a 1-unit increase in the NAO winter index is associated with a 17% decrease in the spring biomass of age-1 cod the following year; ii) this NAO-driven decrease persists as the affected cohort matures; iii) fishing practices appear to exacerbate NAO’s direct biological effect such that, since 1913, a 1-unit increase in the NAO index lowers subsequent cod catch for up to 19 years. The Georges Bank cod stock displays similar patterns. Because we statistically detect a delay between the NAO and subsequent declines in adult biomass, our findings imply that observed current NAO conditions can be used in stock forecasts, providing lead time for adaptive policy. More broadly, our approach can inform forecasting efforts for other fish populations strongly affected by natural and anthropogenic climatic variation. PMID:27463967

  10. The Relationship Between Acoustic Target Strength and Body Length for Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus)

    DTIC Science & Technology

    2010-10-01

    salar), striped bass (Morone saxatilis), orange roughy (Hoplostethus atlanticus), Atlantic cod (Gadus morhua), Atlantic mackerel (Scomber scombrus...55: 2492-2502. Clay, A., and M. Castonguay. 1996. In situ target strengths of Atlantic cod (Gadus morhua) and Atlantic mackerel (Scomber scombrus

  11. DNA barcoding for detecting market substitution in salted cod fillets and battered cod chunks.

    PubMed

    Di Pinto, Angela; Di Pinto, Pietro; Terio, Valentina; Bozzo, Giancarlo; Bonerba, Elisabetta; Ceci, Edmondo; Tantillo, Giuseppina

    2013-12-01

    The Italian Ministry of Agricultural, Food and Forestry Policies (MiPAAF) Decree dated 31 January 2008, which reports the Italian name for fish species of commercial interest, establishes that baccalà can be obtained exclusively from G. macrocephalus (Pacific cod) and G. morhua (Atlantic cod). This paper describes the COI-based DNA identification system to verify the substitution or misbranding of gadoid fish species and, consequently, its concordance with the labels on salted cod fillets shown as baccalà and on battered cod chunks labelled as bocconcini di baccalà. The analysis of interpretable sequences revealed that 55/65 dried salted cod fillet samples were detected as belonging to the family Gadidae, while 10/65 samples appeared to belong to the Lotidae family, while among battered cod chunks labelled as bocconcini di baccalà, the post-sequencing data analysis shows that the labels were completely wrong, with 28/40 samples from Pollachius virens and 12/40 samples from Brosme brosme. The substitution rate for products labelled on the market as baccalà in this study raises significant issues relating to food safety and consumer protection.

  12. Geologic history of Cape Cod, Massachusetts

    USGS Publications Warehouse

    ,

    1976-01-01

    Cape Cod, a sandy peninsula built mostly during the Ice Age, juts into the Atlantic Ocean like a crooked arm. Because of its exposed location, Cape Cod was visited by many early explorers. Although clear-cut evidence is lacking, the Vikings may have sighted this land about 1,000 years ago. It was visited by Samuel de Champlain in 1605, and his detailed descriptions and charts have helped present-day scientists to determine the rate of growth of Nauset Beach marsh and Nauset spit. Bartholomew Gosnold, a lesser known explorer, settled for a short time on the Elizabeth Islands to the southwest and gave Cape Cod its name in 1602. The Pilgrims first landed in America on the tip of Lower Cape Cod after they were turned back from their more southerly destination by shoals between Cape Cod and Nantucket Island. On Cape Cod they found potable water and food and had their first fight with the natives. The Pilgrims, however, decided that this land was too isolated, too exposed, and too sandy to support them, and they sailed across Cape Cod Bay to establish Plymouth. These features remain today. Small villages are separated by large areas of forest, dune, beach, and marsh. This unspoiled natural beauty makes Cape Cod one of the most favored vacation areas for the people living in the thickly settled Northeastern States. Cape Cod is of particular interest to geologists because it was formed by glaciers very recently in terms of geologic time. During the Great Ice Age, (the Pleistocene Epoch which began 2 to 3 million years ago), glaciers advanced from the north into the temperate regions of the Earth. Glacial ice covered the land at least four times. Each advance was accompanied by a worldwide lowering of sea level because the source of the ice was water from the seas. When the glaciers melted, the climate and sea level were probably much like they are today. In fact, some scientists believe that the Earth is presently between glacial episodes and that ice once again will

  13. Effects of climate change on the survival of larval cod

    NASA Astrophysics Data System (ADS)

    Kristiansen, T.; Stock, C. A.; Drinkwater, K. F.; Curchitser, E. N.

    2011-12-01

    Understanding how climate change may impact important commercial fisheries is critical for developing sustainable fisheries management strategies. In this study, we used simulations from an Earth System Model (NOAA GFDL ESM2.1) coupled with an individual-based model (IBM) for larval fish to provide a first assessment of the potential importance of climate-change driven changes in primary productivity and temperature on cod recruitment in the North Atlantic to the year 2100. ESM model output was averaged for 5 regions, each with an area of 5x5 on a latitude-longitude grid, and representing the geographic boundaries of the current cod range. The physical and environmental data were incorporated into a mechanistic IBM used to simulate the critical early phases in the life of larval fish (e.g. cod) in a changing environment. Large phytoplankton production was predicted to decrease in most regions, thereby lowering the number of meso-zooplankton in the water column. Meso-zooplankton is the most important prey item for larval cod and a reduction in their numbers have strong impacts on larval cod survival. The combination of lowered prey abundance with increased energy requirement for growth and metabolism through increased temperature had a negative impact on cod recruitment in all modeled regions of the North Atlantic. The probability of survival past the larval stages was reduced with 20-30% at all five spawning grounds by the year 2100. Together, these results suggest climate change could have significant impacts on the survival of larval cod in the North Atlantic.

  14. Transport of North Sea cod larvae into the Skagerrak coastal populations.

    PubMed Central

    Knutsen, Halvor; André, Carl; Jorde, Per Erik; Skogen, Morten D.; Thuróczy, Emma; Stenseth, Nils Chr

    2004-01-01

    The Atlantic cod (Gadus morhua) is economically one of the world's most important marine species--a species presently suffering from heavy overexploitation throughout its range of distribution. Although not fully understood, the Atlantic cod is believed to be structured into populations in a rather complex manner, whereby both highly migratory and more confined ocean-spawning stocks coexist with stationary coastal populations. Owing to the complex population structure, little is presently known about how overexploitation of offshore stocks may affect other segments of the species. Here, we use microsatellite DNA analyses of coastal and offshore cod in combination with oceanographic modelling to investigate the population structure of Atlantic cod in the North Sea-Skagerrak area and evaluate the potential for larval transport into coastal populations. Our results suggest an extensive but temporally variable drift of offshore cod larvae into coastal populations. In a year (2001) with high inflow of North Sea waters into the Skagerrak we find that juvenile cod caught along the Skagerrak coast are predominantly of North Sea origin, whereas in a year (2000) with low inflow juveniles appear to be of local origin. These findings indicate that offshore cod may influence coastal cod populations over large distances. PMID:15306331

  15. Submarine Hydrogeological Data from Cape Cod National Seashore

    USGS Publications Warehouse

    Cross, VeeAnn A.; Bratton, John F.; Crusius, John; Colman, John A.; McCobb, Timothy D.

    2008-01-01

    In order to test hypotheses about ground water flow under and into estuaries and the Atlantic Ocean, geophysical surveys, geophysical probing, submarine ground-water sampling, and sediment coring were conducted by U.S. Geological Survey (USGS) scientists at Cape Cod National Seashore (CCNS) in Massachusetts from 2004 through 2006. This USGS Open-File Report presents the data collected as a result of these field efforts.

  16. Aspects of the hormonal regulation of appetite in fish with emphasis on goldfish, Atlantic cod and winter flounder: notes on actions and responses to nutritional, environmental and reproductive changes.

    PubMed

    Volkoff, Hélène; Xu, Meiyu; MacDonald, Erin; Hoskins, Leah

    2009-05-01

    In vertebrates including fish, food intake regulation involves intricate networks of hormones produced by both brain and peripheral tissues. Under optimum conditions, nutritional intake is adequate for basal metabolic needs, growth, development, reproduction, and deposition of energy stores. As fish represent a very diverse group, different fish species live in very different environments and are exposed to variations in a wide range of factors, including not only internal factors, such as nutritional/metabolic status and reproductive events but also environmental factors, such as temperature and photoperiod. These physiological responses often include changes in appetite that might occur through modulations of the gene expression and action of feeding-regulating hormones. Despite recent advances, our current understanding of the regulation of feeding in fish is still limited and based primarily on studies involving a few fish species. This review will give a brief overview of our current knowledge of the regulation of feeding by three central (NPY, OX and CART) and two peripheral (ghrelin and GRP) appetite-related factors in a freshwater species, the goldfish (Carassius auratus) and two marine species, cod (Gadus morhua) and winter flounder (Pleuronectes americanus).

  17. Space Radar Image of Cape Cod, Massachusetts

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This spaceborne radar image shows the famous 'hook' of Cape Cod, Massachusetts. The Cape, which juts out into the Atlantic Ocean about 100 kilometers (62 miles) southeast of Boston, actually consists of sandy debris left behind by the great continental ice sheets when they last retreated from southern New England about 20,000 years ago. Today's landscape consists of sandy forests, fields of scrub oak and other bushes and grasses, salt marshes, freshwater ponds, as well as the famous beaches and sand dunes. In this image, thickly forested areas appear green, marshes are dark blue, ponds and sandy areas are black, and developed areas are mostly pink. The dark L-shape in the lower center is the airport runways in Hyannis, the Cape's largest town. The dark X-shape left of the center is Otis Air Force Base. The Cape Cod Canal, above and left of center, connects Buzzards Bay on the left with Cape Cod Bay on the right. The northern tip of the island of Martha's Vineyard is seen in the lower left. The tip of the Cape, in the upper right, includes the community of Provincetown, which appears pink, and the protected National Seashore areas of sand dunes that parallel the Atlantic coast east of Provincetown. Scientists are using radar images like this one to study delicate coastal environments and the effects of human activities on the ecosystem and landscape. This image was acquired by Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour on April 15, 1994. The image is 81.7 kilometers by 43.1 kilometers (50.7 miles by 26.7 miles) and is centered at 41.8 degrees north latitude, 70.3 degrees west longitude. North is toward the upper right. The colors are assigned to different radar frequencies and polarizations of the radar as follows: red is L-band, horizontally transmitted and received; green is C-band, horizontally transmitted, vertically received; and blue is C-band, horizontally transmitted and received. SIR

  18. A comparison between egg trancriptomes of cod and salmon reveals species-specific traits in eggs for each species.

    PubMed

    Wargelius, Anna; Furmanek, Tomasz; Montfort, Jérôme; Le Cam, Aurélie; Kleppe, Lene; Juanchich, Amelie; Edvardsen, Rolf B; Taranger, Geir Lasse; Bobe, Julien

    2015-05-01

    Fish in use in aquaculture display large variation in gamete biology. To reach better understanding around this issue, this study aims at identifying if species specific "egg life history traits" can be hidden in the unfertilized egg. This was done by investigating egg transcriptome differences between Atlantic salmon and Atlantic cod. Salmon and cod eggs were selected due to their largely differencing phenotypes. An oligo microarray analysis was performed on ovulated eggs from cod (n = 8) and salmon (n = 7). The arrays were normalized to a similar spectrum for both arrays. Both arrays were re-annotated with SWISS-Prot and KEGG genes to retrieve an official gene symbol and an orthologous KEGG annotation, in salmon and cod arrays this represented 14,009 and 7,437 genes respectively. The probe linked to the highest gene expression for that particular KEGG annotation was used to compare expression between species. Differential expression was calculated for genes that had an annotation with score >300, resulting in a total of 2,457 KEGG annotations (genes) being differently expressed between the species (FD > 2). This analysis revealed that immune, signal transduction and excretory related pathways were overrepresented in salmon compared to cod. The most overrepresented pathways in cod were related to regulation of genetic information processing and metabolism. To conclude this analysis clearly point at some distinct transcriptome repertoires for cod and salmon and that these differences may explain some of the species-specific biological features for salmon and cod eggs.

  19. Acoustically Induced Streaming Flows near a Model Cod Otolith and their Potential Implications for Fish Hearing

    SciTech Connect

    Kotas, Charlotte W; Rogers, Peter; Yoda, Minami

    2011-01-01

    The ears of fishes are remarkable sensors for the small acoustic disturbances associated with underwater sound. For example, each ear of the Atlantic cod (Gadus morhua) has three dense bony bodies (otoliths) surrounded by fluid and tissue, and detects sounds at frequencies from 30 to 500 Hz. Atlantic cod have also been shown to localize sounds. However, how their ears perform these functions is not fully understood. Steady streaming, or time-independent, flows near a 350% scale model Atlantic cod otolith immersed in a viscous fluid were studied to determine if these fluid flows contain acoustically relevant information that could be detected by the ear s sensory hair cells. The otolith was oscillated sinusoidally at various orientations at frequencies of 8 24 Hz, corresponding to an actual frequency range of 280 830 Hz. Phaselocked particle pathline visualizations of the resulting flows give velocity, vorticity, and rate of strain fields over a single plane of this mainly two-dimensional flow. Although the streaming flows contain acoustically relevant information, the displacements due to these flows are likely too small to explain Atlantic cod hearing abilities near threshold. The results, however, may suggest a possible mechanism for detection of ultrasound in some fish species.

  20. Mercury concentration trend as a possible result of changes in cod population demography.

    PubMed

    Ruus, Anders; Hjermann, Dag Ø; Beylich, Bjørnar; Schøyen, Merete; Øxnevad, Sigurd; Green, Norman W

    2017-07-20

    Mercury (Hg) in Atlantic cod (Gadus morhua) is one of many parameters that are monitored through OSPAR's Joint Assessment and Monitoring Programme. Time series for cod in the Inner Oslofjord (Norway) go back to 1984. Until 2014, annual median Hg-concentrations in cod from the Inner Oslofjord showed both significant upward long-term (whole time series) and short-term (recent 10 years) trends (when 2015 was included, the short-term trend was not significant). However, the median length of the cod sampled also showed upward trends. This may have been caused by low cod recruitment in the area since the start of the 2000s, as indicated by beach seine surveys. To investigate how length would impact the trend analysis, the Hg-concentrations in the cod were normalised to 50 cm. No significant short-term trend in Hg-concentrations could be detected for length-normalised concentrations. The results indicated that most of the upward trend in Hg-concentrations could be attributed to the sampling of larger fish. The reasons for the apparent change in the cod population demography are not conclusive, however, sampling bias must also be considered. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. 77 FR 9699 - Cape Cod National Seashore Advisory Commission; Cape Cod National Seashore, South Wellfleet, MA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-17

    ... National Park Service Cape Cod National Seashore Advisory Commission; Cape Cod National Seashore, South... Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on March...

  2. 76 FR 8768 - Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... National Park Service Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory... Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on March...

  3. 76 FR 44606 - Cape Cod National Seashore; South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-26

    ... National Park Service Cape Cod National Seashore; South Wellfleet, MA; Cape Cod National Seashore Advisory.... 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on September...

  4. 76 FR 66082 - Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-25

    ... National Park Service Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory... Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on...

  5. 76 FR 81965 - Cape Cod National Seashore Advisory Commission; Cape Cod National Seashore, South Wellfleet, MA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-29

    ... National Park Service Cape Cod National Seashore Advisory Commission; Cape Cod National Seashore, South... Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on...

  6. 75 FR 34479 - Cape Cod National Seashore; South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-17

    ... National Park Service Cape Cod National Seashore; South Wellfleet, MA; Cape Cod National Seashore Advisory... Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on July...

  7. 75 FR 5622 - Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory Commission AGENCY.... App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on March 22, 2010 at 1...

  8. 75 FR 77900 - Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ... National Park Service Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory... Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on...

  9. 75 FR 63854 - Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ... National Park Service Cape Cod National Seashore, South Wellfleet, MA; Cape Cod National Seashore Advisory... Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission will be held on...

  10. 75 FR 20380 - Cape Cod National Seashore; South Wellfleet, Massachusetts; Cape Cod National Seashore Advisory...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ... National Park Service Cape Cod National Seashore; South Wellfleet, Massachusetts; Cape Cod National... (Pub. L. 92-463, 86 Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The meeting of the Cape Cod National Seashore Advisory Commission...

  11. 75 FR 5541 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Inshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod for... Pacific cod apportioned to vessels catching Pacific cod for processing by the inshore component of...

  12. 75 FR 10441 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-08

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Offshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod for... Pacific cod apportioned to vessels catching Pacific cod for processing by the offshore component of...

  13. 75 FR 8839 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Offshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod for... Pacific cod apportioned to vessels catching Pacific cod for processing by the offshore component of...

  14. 75 FR 7976 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Inshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod for... Pacific cod apportioned to vessels catching Pacific cod for processing by the inshore component of...

  15. Organochlorines including polychlorinated biphenyls in muscle, liver, and ovaries of cod, Gadus morhua

    SciTech Connect

    Hellou, J.; Warren, W.G.; Payne, J.F. )

    1993-11-01

    Twenty-three specific organochlorine contaminants and polychlorinated biphenyls (PCBs), measured as three Aroclor standards were analyzed in muscle, liver, and ovaries of cod, Gadus morhua, collected in the Northwest Atlantic. In general, contaminants were undetectable in muscle tissue, while concentrations were 10 times lower in ovaries than liver (wet weight). Comparison of results to other locations indicated a similarity between the ratio of the concentrations of p,p'-DDE, p,p'-DDD and p,p'-DDT, in liver of cod from the northern North Sea and from the Northwest Atlantic, although with lower levels in the present study. The ratio of alpha-HCH and gamma-HCH was between that of the central and northern North Sea. Similar ratios tend to indicate similar residence times in the atmosphere, from source to sampling area. Comparison of sigma PCB and sigma DDT in the liver of cod from various geographical locations showed the following general trend in concentrations: Arctic, Northwest Atlantic, West Atlantic, Norway < North Baltic, Nova Scotia, North Sea < South Baltic. It was observed that if the liver concentration of one compound was low (high), there was a tendency for all compounds to be low (high). Cluster analysis of organochlorines in liver pointed to the presence of four basic clusters, which could reflect similar physical chemical properties within a group. Concentrations of organochlorines in ovaries were below levels expected to affect egg and larval viability.

  16. MISR Looks at Cape Cod

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Each year in late November the United States observes the Thanksgiving holiday, commemorating the harvest festival celebrated by the Plymouth colonists and the Native Americans who helped them survive the devastating winter of 1620. Plymouth, Massachusetts, where the Mayflower Pilgrims landed, is located on the west side of Cape Cod Bay, shown in this MISR vertical-viewing (nadir) camera image. This nearly cloud-free picture was acquired on April 13, 2000 during Terra orbit 1708.

    South of the distinctively-shaped Cape Cod are Nantucket Island and Martha's Vineyard. Further west is Block Island, south of Narragansett Bay, Rhode Island. Montauk Point on the eastern tip of Long Island, New York, is visible at the lower left. On the mainland, Providence and Boston appear as gray patches. Jutting out from the Massachusetts coastline, northeast of Boston, is Cape Ann, location of the city of Gloucester, which was settled soon after the Pilgrim's arrival in Plymouth. Gloucester is the oldest fishing port in the eastern United States.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  17. Calcium from salmon and cod bone is well absorbed in young healthy men: a double-blinded randomised crossover design

    PubMed Central

    2010-01-01

    Background Calcium (Ca) - fortified foods are likely to play an important role in helping the consumer achieve an adequate Ca intake, especially for persons with a low intake of dairy products. Fish bones have a high Ca content, and huge quantities of this raw material are available as a by-product from the fish industry. Previously, emphasis has been on producing high quality products from fish by-products by use of bacterial proteases. However, documentation of the nutritional value of the enzymatically rinsed Ca-rich bone fraction remains unexplored. The objective of the present study was to assess the bioavailability of calcium in bones of Atlantic salmon (oily fish) and Atlantic cod (lean fish) in a double-blinded randomised crossover design. Methods Ca absorption was measured in 10 healthy young men using 47Ca whole body counting after ingestion of a test meal extrinsically labelled with the 47Ca isotope. The three test meals contained 800 mg of Ca from three different calcium sources: cod bones, salmon bones and control (CaCO3). Results Mean Ca absorption (± SEE) from the three different Ca sources were 21.9 ± 1.7%, 22.5 ± 1.7% and 27.4 ± 1.8% for cod bones, salmon bones, and control (CaCO3), respectively. Conclusion We conclude that bones from Atlantic salmon and Atlantic cod are suitable as natural Ca sources in e.g. functional foods or as supplements. PMID:20646299

  18. Calcium from salmon and cod bone is well absorbed in young healthy men: a double-blinded randomised crossover design.

    PubMed

    Malde, Marian K; Bügel, Susanne; Kristensen, Mette; Malde, Ketil; Graff, Ingvild E; Pedersen, Jan I

    2010-07-20

    Calcium (Ca) - fortified foods are likely to play an important role in helping the consumer achieve an adequate Ca intake, especially for persons with a low intake of dairy products. Fish bones have a high Ca content, and huge quantities of this raw material are available as a by-product from the fish industry. Previously, emphasis has been on producing high quality products from fish by-products by use of bacterial proteases. However, documentation of the nutritional value of the enzymatically rinsed Ca-rich bone fraction remains unexplored. The objective of the present study was to assess the bioavailability of calcium in bones of Atlantic salmon (oily fish) and Atlantic cod (lean fish) in a double-blinded randomised crossover design. Ca absorption was measured in 10 healthy young men using 47Ca whole body counting after ingestion of a test meal extrinsically labelled with the 47Ca isotope. The three test meals contained 800 mg of Ca from three different calcium sources: cod bones, salmon bones and control (CaCO3). Mean Ca absorption (+/- SEE) from the three different Ca sources were 21.9 +/- 1.7%, 22.5 +/- 1.7% and 27.4 +/- 1.8% for cod bones, salmon bones, and control (CaCO3), respectively. We conclude that bones from Atlantic salmon and Atlantic cod are suitable as natural Ca sources in e.g. functional foods or as supplements.

  19. Comment on "Slow adaptation in the face of rapid warming leads to collapse of the Gulf of Maine cod fishery".

    PubMed

    Palmer, Michael C; Deroba, Jonathan J; Legault, Christopher M; Brooks, Elizabeth N

    2016-04-22

    Pershing et al (Reports, 13 November, p. 809) concluded that failure to account for temperature in the assessment and management of Gulf of Maine Atlantic cod caused overfishing. We argue that the "extra mortality" calculation driving this conclusion is an artifact. Environmental factors affect all stocks, but attribution of additional mortality to temperature alone by Pershing et al is unsupported by the data.

  20. 75 FR 64957 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-21

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Offshore...; closure. ] SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod... to vessels catching Pacific cod for processing by the offshore component of the Western...

  1. 75 FR 56016 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-15

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Inshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod for... catching Pacific cod for processing by the inshore component of the Central Regulatory Area of the...

  2. 75 FR 63402 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Inshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod for... catching Pacific cod for processing by the inshore component of the Western Regulatory Area of the...

  3. 75 FR 64956 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-21

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Catching Pacific Cod for Processing by the Offshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels catching Pacific cod for... catching Pacific cod for processing by the offshore component of the Central Regulatory Area of the...

  4. Condition, prolonged swimming performance and muscle metabolic capacities of cod Gadus morhua.

    PubMed

    Martínez, M; Guderley, H; Dutil, J-D; Winger, P D; He, P; Walsh, S J

    2003-02-01

    This study evaluated the link between swimming endurance and condition of Atlantic cod Gadus morhua that had been fed or starved during the 16 weeks preceding the tests, and assessed whether muscle metabolic capacities explain such links. The condition factor [(somatic mass x fork length(-3))x100] of starved cod was 0.54+/-0.1 whereas that of fed cod was 0.81+/-0.1. In white and red muscle, we measured four glycolytic enzymes: phosphofructokinase (PFK), pyruvate kinase (PK), creatine kinase (CK) and lactate dehydrogenase (LDH), two mitochondrial enzymes: cytochrome c oxidase (CCO) and citrate synthase (CS), a biosynthetic enzyme, nucleoside diphosphate kinase (NDPK), glycogen and protein levels and water content. Muscle samples were taken at three positions along the length of the fish; starvation affected the metabolic capacities of white muscle more than those of red muscle. The levels of glycolytic enzymes and glycogen changed more in white than red muscle during starvation. Both in fed and starved cod, muscle metabolic capacities varied with position along the fish; starvation reduced this longitudinal variation more in white than red muscle. In white muscle of fed cod, the glycolytic enzyme levels increased from head to tail, while in starved cod this longitudinal variation disappeared. In red muscle mitochondrial enzyme levels were highest in the caudal sample, but fewer differences were found for glycolytic enzymes. Swimming endurance was markedly affected by fish condition, with starved fish swimming only 30% of the time (and distance) of fed fish. This endurance was closely linked with the number of burst-coast movements during the test and the activity of CCO and LDH in white muscle. The number of burst-coast movements was significantly linked with condition factor and PFK activity in caudal red muscle and gill arch mass. Our data indicated that cod use both glycolytic and oxidative capacities to support endurance swimming. Furthermore, swimming endurance

  5. Alternative adaptive immunity strategies: coelacanth, cod and shark immunity.

    PubMed

    Buonocore, Francesco; Gerdol, Marco

    2016-01-01

    The advent of high throughput sequencing has permitted to investigate the genome and the transcriptome of novel non-model species with unprecedented depth. This technological advance provided a better understanding of the evolution of adaptive immune genes in gnathostomes, revealing several unexpected features in different fish species which are of particular interest. In the present paper, we review the current understanding of the adaptive immune system of the coelacanth, the elephant shark and the Atlantic cod. The study of coelacanth, the only living extant of the long thought to be extinct Sarcopterygian lineage, is fundamental to bring new insights on the evolution of the immune system in higher vertebrates. Surprisingly, coelacanths are the only known jawed vertebrates to lack IgM, whereas two IgD/W loci are present. Cartilaginous fish are of great interest due to their basal position in the vertebrate tree of life; the genome of the elephant shark revealed the lack of several important immune genes related to T cell functions, which suggest the existence of a primordial set of TH1-like cells. Finally, the Atlantic cod lacks a functional major histocompatibility II complex, but balances this evolutionary loss with the expansion of specific gene families, including MHC I, Toll-like receptors and antimicrobial peptides. Overall, these data point out that several fish species present an unconventional adaptive immune system, but the loss of important immune genes is balanced by adaptive evolutionary strategies which still guarantee the establishment of an efficient immune response against the pathogens they have to fight during their life. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Who's your mama? Riverine hybridisation of threatened freshwater Trout Cod and Murray Cod.

    PubMed

    Couch, Alan J; Unmack, Peter J; Dyer, Fiona J; Lintermans, Mark

    2016-01-01

    Rates of hybridization and introgression are increasing dramatically worldwide because of translocations, restocking of organisms and habitat modifications; thus, determining whether hybridization is occuring after reintroducing extirpated congeneric species is commensurately important for conservation. Restocking programs are sometimes criticized because of the genetic consequences of hatchery-bred fish breeding with wild populations. These concerns are important to conservation restocking programs, including those from the Australian freshwater fish family, Percichthyidae. Two of the better known Australian Percichthyidae are the Murray Cod, Maccullochella peelii and Trout Cod, Maccullochella macquariensis which were formerly widespread over the Murray Darling Basin. In much of the Murrumbidgee River, Trout Cod and Murray Cod were sympatric until the late 1970s when Trout Cod were extirpated. Here we use genetic single nucleotide polymorphism (SNP) data together with mitochondrial sequences to examine hybridization and introgression between Murray Cod and Trout Cod in the upper Murrumbidgee River and consider implications for restocking programs. We have confirmed restocked riverine Trout Cod reproducing, but only as inter-specific matings, in the wild. We detected hybrid Trout Cod-Murray Cod in the Upper Murrumbidgee, recording the first hybrid larvae in the wild. Although hybrid larvae, juveniles and adults have been recorded in hatcheries and impoundments, and hybrid adults have been recorded in rivers previously, this is the first time fertile F1 have been recorded in a wild riverine population. The F1 backcrosses with Murray cod have also been found to be fertile. All backcrosses noted were with pure Murray Cod. Such introgression has not been recorded previously in these two species, and the imbalance in hybridization direction may have important implications for restocking programs.

  7. Historical Arctic Logbooks Provide Insights into Past Diets and Climatic Responses of Cod

    PubMed Central

    Townhill, Bryony L.; Maxwell, David; Engelhard, Georg H.; Simpson, Stephen D.; Pinnegar, John K.

    2015-01-01

    Gadus morhua (Atlantic cod) stocks in the Barents Sea are currently at levels not seen since the 1950s. Causes for the population increase last century, and understanding of whether such large numbers will be maintained in the future, are unclear. To explore this, we digitised and interrogated historical cod catch and diet datasets from the Barents Sea. Seventeen years of catch data and 12 years of prey data spanning 1930–1959 cover unexplored spatial and temporal ranges, and importantly capture the end of a previous warm period, when temperatures were similar to those currently being experienced. This study aimed to evaluate cod catch per unit effort and prey frequency in relation to spatial, temporal and environmental variables. There was substantial spatio-temporal heterogeneity in catches through the time series. The highest catches were generally in the 1930s and 1940s, although at some localities more cod were recorded late in the 1950s. Generalized Additive Models showed that environmental, spatial and temporal variables are all valuable descriptors of cod catches, with the highest occurring from 15–45°E longitude and 73–77°N latitude, at bottom temperatures between 2 and 4°C and at depths between 150 and 250 m. Cod diets were highly variable during the study period, with frequent changes in the relative frequencies of different prey species, particularly Mallotus villosus (capelin). Environmental variables were particularly good at describing the importance of capelin and Clupea harengus (herring) in the diet. These new analyses support existing knowledge about how the ecology of the region is controlled by climatic variability. When viewed in combination with more recent data, these historical relationships will be valuable in forecasting the future of Barents Sea fisheries, and in understanding how environments and ecosystems may respond. PMID:26331271

  8. Historical Arctic Logbooks Provide Insights into Past Diets and Climatic Responses of Cod.

    PubMed

    Townhill, Bryony L; Maxwell, David; Engelhard, Georg H; Simpson, Stephen D; Pinnegar, John K

    2015-01-01

    Gadus morhua (Atlantic cod) stocks in the Barents Sea are currently at levels not seen since the 1950s. Causes for the population increase last century, and understanding of whether such large numbers will be maintained in the future, are unclear. To explore this, we digitised and interrogated historical cod catch and diet datasets from the Barents Sea. Seventeen years of catch data and 12 years of prey data spanning 1930-1959 cover unexplored spatial and temporal ranges, and importantly capture the end of a previous warm period, when temperatures were similar to those currently being experienced. This study aimed to evaluate cod catch per unit effort and prey frequency in relation to spatial, temporal and environmental variables. There was substantial spatio-temporal heterogeneity in catches through the time series. The highest catches were generally in the 1930s and 1940s, although at some localities more cod were recorded late in the 1950s. Generalized Additive Models showed that environmental, spatial and temporal variables are all valuable descriptors of cod catches, with the highest occurring from 15-45°E longitude and 73-77°N latitude, at bottom temperatures between 2 and 4°C and at depths between 150 and 250 m. Cod diets were highly variable during the study period, with frequent changes in the relative frequencies of different prey species, particularly Mallotus villosus (capelin). Environmental variables were particularly good at describing the importance of capelin and Clupea harengus (herring) in the diet. These new analyses support existing knowledge about how the ecology of the region is controlled by climatic variability. When viewed in combination with more recent data, these historical relationships will be valuable in forecasting the future of Barents Sea fisheries, and in understanding how environments and ecosystems may respond.

  9. The dangers of ignoring stock complexity in fishery management: the case of the North Sea cod.

    PubMed

    Hutchinson, William F

    2008-12-23

    The plight of the marine fisheries is attracting increasing attention as unsustainably high exploitation levels, exacerbated by more extreme climatic conditions, are driving stocks to the point of collapse. The North Atlantic cod (Gadus morhua), a species which until recently formed a major component of the demersal fisheries, has undergone significant declines across its range. The North Sea stock is typical of many, with a spawning stock biomass that has remained below the safe biological limit since 2000 and recruitment levels near the lowest on record. Cod within the North Sea are currently managed as a single stock, and yet mounting empirical evidence supports the existence of a metapopulation of regionally variable, genetically distinct, sub-stocks. Applying the same management strategies to multiple stocks that differ in their resilience to exploitation inevitably results in the overfishing and likely collapse of the weaker components. Indeed, recent studies have identified two North Sea spawning stocks that have undergone disproportionally large collapses with very substantial reductions in egg production. Similarly affected cod stocks in the northwest Atlantic have shown little evidence of recovery, despite fishery closures. The possible implications of ignoring sub-structuring within management units for biocomplexity, local adaptation and ecosystem stability are considered.

  10. Who’s your mama? Riverine hybridisation of threatened freshwater Trout Cod and Murray Cod

    PubMed Central

    Unmack, Peter J.; Dyer, Fiona J.; Lintermans, Mark

    2016-01-01

    Rates of hybridization and introgression are increasing dramatically worldwide because of translocations, restocking of organisms and habitat modifications; thus, determining whether hybridization is occuring after reintroducing extirpated congeneric species is commensurately important for conservation. Restocking programs are sometimes criticized because of the genetic consequences of hatchery-bred fish breeding with wild populations. These concerns are important to conservation restocking programs, including those from the Australian freshwater fish family, Percichthyidae. Two of the better known Australian Percichthyidae are the Murray Cod, Maccullochella peelii and Trout Cod, Maccullochella macquariensis which were formerly widespread over the Murray Darling Basin. In much of the Murrumbidgee River, Trout Cod and Murray Cod were sympatric until the late 1970s when Trout Cod were extirpated. Here we use genetic single nucleotide polymorphism (SNP) data together with mitochondrial sequences to examine hybridization and introgression between Murray Cod and Trout Cod in the upper Murrumbidgee River and consider implications for restocking programs. We have confirmed restocked riverine Trout Cod reproducing, but only as inter-specific matings, in the wild. We detected hybrid Trout Cod–Murray Cod in the Upper Murrumbidgee, recording the first hybrid larvae in the wild. Although hybrid larvae, juveniles and adults have been recorded in hatcheries and impoundments, and hybrid adults have been recorded in rivers previously, this is the first time fertile F1 have been recorded in a wild riverine population. The F1 backcrosses with Murray cod have also been found to be fertile. All backcrosses noted were with pure Murray Cod. Such introgression has not been recorded previously in these two species, and the imbalance in hybridization direction may have important implications for restocking programs. PMID:27812407

  11. 76 FR 63564 - Pacific Cod by Vessels Harvesting Pacific Cod for Processing by the Inshore Component in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ... Atmospheric Administration 50 CFR Part 679 [Docket No. 101126522-0640-02] RIN 0648-XA759 Pacific Cod by Vessels Harvesting Pacific Cod for Processing by the Inshore Component in the Central Regulatory Area of... for Pacific cod by vessels harvesting Pacific cod for processing by the inshore component in...

  12. 76 FR 80266 - Pacific Cod by Vessels Catching Pacific Cod for Processing by the Inshore Component of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-23

    ... Administration 50 CFR Part 679 [Docket No. 101126522-0640-02] RIN 0648-XA886 Pacific Cod by Vessels Catching Pacific Cod for Processing by the Inshore Component of the Central Regulatory Area of the Gulf of Alaska... Pacific cod by vessels catching Pacific cod for processing by the inshore component in the...

  13. Substrate mediates consumer control of salt marsh cordgrass on Cape Cod, New England.

    PubMed

    Bertness, Mark D; Holdredge, Christine; Altieri, Andrew H

    2009-08-01

    Cordgrass die-offs in Cape Cod, Massachusetts, USA, salt marshes have challenged the view that the primary production of New England salt marshes is controlled by physical factors. These die-offs have increased dramatically over the last decade and are caused by the common herbivorous marsh crab Sesarma reticulatum, but other factors that control crab impacts remain unclear. We examined the influence of plant nutrient supply and disturbances on Sesarma herbivory by fertilizing plots and creating experimental disturbances, since previous studies have revealed that they mediate the intensity of herbivory in other Western Atlantic marshes. Neither nutrient enrichment nor experimental disturbances affected crab grazing intensity despite their strong effects in other marsh systems. Within and among Cape Cod salt marshes, however, Sesarma burrows are concentrated on peat substrate. Surveys of 10 Cape Cod marshes revealed that burrow density, depth, and complexity are all much higher on peat than on sand or mud substrate, and paralleling these patterns, crab abundance, herbivore pressure, and the expansion of die-off areas are markedly higher on peat than on other substrates. Complementing work hypothesizing that predator release is triggering increased crab herbivory in Cape Cod marshes, these results suggest that cordgrass die-offs are constrained to the peat substrate commonly found on the leading edge of marshes and that the vulnerability of New England salt marshes to crab herbivory and future die-offs may be predictable.

  14. LATITUDINAL GRADIENTS IN BENTHIC COMMUNITY COMPOSITION IN WESTERN ATLANTIC ESTUARIES

    EPA Science Inventory

    The community structure of benthic macroinvertebrates from estuaries along the Atlantic coast of North America from Cape Cod, MA, to Biscayne Bay, FL, were compared. Benthic data were collected over a 5 year period (1990 to 1995) by the U.S. Environmental Protection Agency's Envi...

  15. LATITUDINAL GRADIENTS IN BENTHIC COMMUNITY COMPOSITION IN WESTERN ATLANTIC ESTUARIES

    EPA Science Inventory

    The community structure of benthic macroinvertebrates from estuaries along the Atlantic coast of North America from Cape Cod, MA, to Biscayne Bay, FL, were compared. Benthic data were collected over a 5 year period (1990 to 1995) by the U.S. Environmental Protection Agency's Envi...

  16. CHARACTERIZATION OF WESTERN NORTH ATLANTIC RIGHT WHALE SPRING FEEDING HABITAT

    EPA Science Inventory

    The Great South Channel region of the southwestern Gulf of Maine, between George's Bank and Cape Cod, is the primary spring feeding ground for the western North Atlantic population of the I northern right whale, E. glacialis .Since this whale is so endangered, it is critical to i...

  17. CHARACTERIZATION OF WESTERN NORTH ATLANTIC RIGHT WHALE SPRING FEEDING HABITAT

    EPA Science Inventory

    The Great South Channel region of the southwestern Gulf of Maine, between George's Bank and Cape Cod, is the primary spring feeding ground for the western North Atlantic population of the I northern right whale, E. glacialis .Since this whale is so endangered, it is critical to i...

  18. Ancient DNA reveals the Arctic origin of Viking Age cod from Haithabu, Germany

    PubMed Central

    Star, Bastiaan; Boessenkool, Sanne; Gondek, Agata T.; Nikulina, Elena A.; Hufthammer, Anne Karin; Pampoulie, Christophe; Knutsen, Halvor; André, Carl; Nistelberger, Heidi M.; Dierking, Jan; Petereit, Christoph; Heinrich, Dirk; Jakobsen, Kjetill S.; Stenseth, Nils Chr.; Jentoft, Sissel

    2017-01-01

    Knowledge of the range and chronology of historic trade and long-distance transport of natural resources is essential for determining the impacts of past human activities on marine environments. However, the specific biological sources of imported fauna are often difficult to identify, in particular if species have a wide spatial distribution and lack clear osteological or isotopic differentiation between populations. Here, we report that ancient fish-bone remains, despite being porous, brittle, and light, provide an excellent source of endogenous DNA (15–46%) of sufficient quality for whole-genome reconstruction. By comparing ancient sequence data to that of modern specimens, we determine the biological origin of 15 Viking Age (800–1066 CE) and subsequent medieval (1066–1280 CE) Atlantic cod (Gadus morhua) specimens from excavation sites in Germany, Norway, and the United Kingdom. Archaeological context indicates that one of these sites was a fishing settlement for the procurement of local catches, whereas the other localities were centers of trade. Fish from the trade sites show a mixed ancestry and are statistically differentiated from local fish populations. Moreover, Viking Age samples from Haithabu, Germany, are traced back to the North East Arctic Atlantic cod population that has supported the Lofoten fisheries of Norway for centuries. Our results resolve a long-standing controversial hypothesis and indicate that the marine resources of the North Atlantic Ocean were used to sustain an international demand for protein as far back as the Viking Age. PMID:28784790

  19. An Oscillating Jet in the Cape Cod Bay

    NASA Astrophysics Data System (ADS)

    Poulin, F. J.; Flierl, G. R.

    2004-05-01

    During the spring months, the Cape Cod Bay is a roaming ground for the North Atlantic right whale, perhaps the most endangered whale species in the world. The whales are observed to travel along the topographic steps that run parallel to the shore, eating plankton patches that form in the coastal water. In this region, off the coast of Provincetown, there is an oscillatory current with the same period as that of the ambient tides. The location of the current and its periodicity suggest that the topography and tides play fundamental roles in generating the jet. This current, depending on its velocity profile, may become unstable and generate vortices. It is likely that the local surface convergences and divergences in the tidal flows and vortices are related to the aggregation of the copepods (Calanus Finmarchicus), which are the right whale's primary food source. Understanding the dynamics of this jet is essential to predicting the spatial and temporal patterns of the codepods, which will in turn help us understand the likely locations and feeding history of the whales. In this talk we discuss results of the first phase of this study, that of the oscillatory jet in the Cape Cod Bay. This jet is rather complicated since it involves complex topography and coastlines, bottom and lateral friction, stratification and numerous other effects. Rather than study this system in fine detail, we investigate an idealized model that captures the essential features. In the context of this model, we first compute possible profiles for the oscillating jet. We then solve the linear stability problem to determine how the growth rates depend on the various parameters. Finally, and most importantly, we study the nonlinear problem to observe the time evolution of the instability process along with its equilibration. This provides some insight into how the instabilities are related to fluid transport across the shelf.

  20. Chemical quality of ground water on Cape Cod, Massachusetts

    USGS Publications Warehouse

    Frimpter, M.H.; Gay, F.B.

    1979-01-01

    Cape Cod is a 440 square mile hook-shaped peninsula which extends 40 miles into the Atlantic. Freshwater in Pleistocene sand and gravel deposits is the source of supply for nearly 100 municipal and thousands of private domestic wells. Most ground water on Cape Cod is of good chemical quality for drinking and other uses. It is characteristically low in dissolved solids and is soft. In 90 percent of the samples analyzed, dissolved solids were less than 100 mg/l (milligrams per liter) and pH was less than 7.0. Highway deicing salt, sea-water flooding due to storms , and saltwater intrusion due to ground-water withdrawal are sources of sodium chloride contamination. Chloride concentrations have increased from 20 to 140 mg/l, owing to saltwater intrusion at Provincetown 's wells in Truro. In Yarmouth, contaminated ground water near a salt-storage area contained as much as 1,800 mg/l chloride. Heavy metals, insecticides, and herbicides were not found at concentrations above the U.S. Environmental Protection Agency 's recommended limits for public drinking-water supplies, but iron and manganese in some samples exceeded those limits. Ninety percent of 84 samples analyzed for nitrate reported as nitrogen contained less than 1.3 mg/l and 80 percent contained 0.5 mg/l or less of nitrate as nitrogen. Water containing nitrogen in excess of 0.5 mg/l has probably been affected by municipal or domestic sewage or fertilizer, and water with less than this amount may have been affected by them. (Woodard-USGS)

  1. Slow adaptation in the face of rapid warming leads to collapse of the Gulf of Maine cod fishery.

    PubMed

    Pershing, Andrew J; Alexander, Michael A; Hernandez, Christina M; Kerr, Lisa A; Le Bris, Arnault; Mills, Katherine E; Nye, Janet A; Record, Nicholas R; Scannell, Hillary A; Scott, James D; Sherwood, Graham D; Thomas, Andrew C

    2015-11-13

    Several studies have documented fish populations changing in response to long-term warming. Over the past decade, sea surface temperatures in the Gulf of Maine increased faster than 99% of the global ocean. The warming, which was related to a northward shift in the Gulf Stream and to changes in the Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation, led to reduced recruitment and increased mortality in the region's Atlantic cod (Gadus morhua) stock. Failure to recognize the impact of warming on cod contributed to overfishing. Recovery of this fishery depends on sound management, but the size of the stock depends on future temperature conditions. The experience in the Gulf of Maine highlights the need to incorporate environmental factors into resource management.

  2. Mechanistic insights into the effects of climate change on larval cod.

    PubMed

    Kristiansen, Trond; Stock, Charles; Drinkwater, Kenneth F; Curchitser, Enrique N

    2014-05-01

    Understanding the biophysical mechanisms that shape variability in fisheries recruitment is critical for estimating the effects of climate change on fisheries. In this study, we used an Earth System Model (ESM) and a mechanistic individual-based model (IBM) for larval fish to analyze how climate change may impact the growth and survival of larval cod in the North Atlantic. We focused our analysis on five regions that span the current geographical range of cod and are known to contain important spawning populations. Under the SRES A2 (high emissions) scenario, the ESM-projected surface ocean temperatures are expected to increase by >1 °C for 3 of the 5 regions, and stratification is expected to increase at all sites between 1950-1999 and 2050-2099. This enhanced stratification is projected to decrease large (>5 μm ESD) phytoplankton productivity and mesozooplankton biomass at all 5 sites. Higher temperatures are projected to increase larval metabolic costs, which combined with decreased food resources will reduce larval weight, increase the probability of larvae dying from starvation and increase larval exposure to visual and invertebrate predators at most sites. If current concentrations of piscivore and invertebrate predators are maintained, larval survival is projected to decrease at all five sites by 2050-2099. In contrast to past observed responses to climate variability in which warm anomalies led to better recruitment in cold-water stocks, our simulations indicated that reduced prey availability under climate change may cause a reduction in larval survival despite higher temperatures in these regions. In the lower prey environment projected under climate change, higher metabolic costs due to higher temperatures outweigh the advantages of higher growth potential, leading to negative effects on northern cod stocks. Our results provide an important first large-scale assessment of the impacts of climate change on larval cod in the North Atlantic. © 2013 John

  3. Cod (Gadus morhua) muscle proteome cataloging using 1D-PAGE protein separation, nano-liquid chromatography peptide fractionation, and linear trap quadrupole (LTQ) mass spectrometry.

    PubMed

    Gebriel, Mohammed; Uleberg, Kai-Erik; Larssen, Eivind; Bjørnstad, Anne Hjelle; Sivertsvik, Morten; Møller, Simon Geir

    2010-12-08

    Because Atlantic cod (Gadus morhua) has high economic value and its protein-rich muscle tissue is a food source, an increased understanding of the effects and consequences of environmental, nutritional, biological, and industrial factors on meat quality is necessary. To gain insight into cod muscle tissue protein composition, a large-scale proteomics approach has been used. One-dimensional polyacrylamide gel electrophoresis, nanoflow liquid chromatography peptide separation, and linear trap quadrupole mass spectrometry were used to identify 4804 peptides, which retrieved 9113 cod expressed sequence tags (ESTs), which in turn were mapped to 446 unique proteins. The same data set identified 3924 proteins from the zebrafish protein database, which highlights the complementary value of the two approaches. The generated data sets will act as a foundation for studies related to physiological status assessment of cod under different environmental conditions, screening for diseases, and biomarker identification for assessment of fish quality during industrial processing and preservation.

  4. A modified method for COD determination of solid waste, using a commercial COD kit and an adapted disposable weighing support.

    PubMed

    André, L; Pauss, A; Ribeiro, T

    2017-03-01

    The chemical oxygen demand (COD) is an essential parameter in waste management, particularly when monitoring wet anaerobic digestion processes. An adapted method to determine COD was developed for solid waste (total solids >15%). This method used commercial COD tubes and did not require sample dilution. A homemade plastic weighing support was used to transfer the solid sample into COD tubes. Potassium hydrogen phthalate and glucose used as standards showed an excellent repeatability. A small underestimation of the theoretical COD value (standard values around 5% lower than theoretical values) was also observed, mainly due to the intrinsic COD of the weighing support and to measurement uncertainties. The adapted COD method was tested using various solid wastes in the range of 1-8 mgCOD, determining the COD of dried and ground cellulose, cattle manure, straw and a mixed-substrate sample. This new adapted method could be used to monitor and design dry anaerobic digestion processes.

  5. Climate and population density drive changes in cod body size throughout a century on the Norwegian coast.

    PubMed

    Rogers, Lauren A; Stige, Leif C; Olsen, Esben M; Knutsen, Halvor; Chan, Kung-Sik; Stenseth, Nils Chr

    2011-02-01

    Understanding how populations respond to changes in climate requires long-term, high-quality datasets, which are rare for marine systems. We estimated the effects of climate warming on cod lengths and length variability using a unique 91-y time series of more than 100,000 individual juvenile cod lengths from surveys that began in 1919 along the Norwegian Skagerrak coast. Using linear mixed-effects models, we accounted for spatial population structure and the nested structure of the survey data to reveal opposite effects of spring and summer warming on juvenile cod lengths. Warm summer temperatures in the coastal Skagerrak have limited juvenile growth. In contrast, warmer springs have resulted in larger juvenile cod, with less variation in lengths within a cohort, possibly because of a temperature-driven contraction in the spring spawning period. A density-dependent reduction in length was evident only at the highest population densities in the time series, which have rarely been observed in the last decade. If temperatures rise because of global warming, nonlinearities in the opposing temperature effects suggest that negative effects of warmer summers will increasingly outweigh positive effects of warmer springs, and the coastal Skagerrak will become ill-suited for Atlantic cod.

  6. Exophthalmia in wild-caught cod (Gadus morhua L.): development of a secondary barotrauma effect in captivity.

    PubMed

    Humborstad, O-B; Ferter, K; Kryvi, H; Fjelldal, P G

    2017-01-01

    Capture-based aquaculture (CBA) of Atlantic cod (Gadus morhua) has become increasingly important in recent years, and increased attention is being paid to animal welfare issues linked to these activities. Earlier studies showed that some cod develop secondary exophthalmia in captivity. This study investigated the development of secondary exophthalmia in two groups of wild-caught cod, one of which was exposed to rapid decompression causing acute barotrauma (treatment group) while the other was not (control group). Photographs and radiographs before and up to 33 days after barotrauma revealed a significant increase in overall eye protrusion caused by an accumulation of gas in the orbita in the treatment group, first observed on day 9 after decompression, while no protrusions were observed in the control group. Barotrauma was thus identified as an important trigger for the development of secondary uni- or bilateral exophthalmia of wild-caught cod. Two underlying mechanisms are suggested, where the more likely is residual swim bladder gas taking the route of least resistance, while the less likely is the exsolution of gas from the blood. Our results have implications for a wide range of contexts in which cod are rapidly brought to the surface from great depth. © 2016 John Wiley & Sons Ltd.

  7. 44. CAPE COD AIR STATION PAVE PAWS FACILITY BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. CAPE COD AIR STATION PAVE PAWS FACILITY - BUILDING ELEVATION WITH BUILDING METAL SIDING BEING APPLIED ON "B" FACE. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  8. 76 FR 59922 - Pacific Cod by Non-American Fisheries Act Crab Vessels Harvesting Pacific Cod for Processing by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-28

    ... Fisheries Act Crab Vessels Harvesting Pacific Cod for Processing by the Inshore Component in the Western... directed fishing for Pacific cod by non- American Fisheries Act (AFA) crab vessels that are subject to... sideboard limit established for non-AFA crab vessels harvesting Pacific cod for processing by the inshore...

  9. 76 FR 58414 - Pacific Cod by Non-American Fisheries Act Crab Vessels Harvesting Pacific Cod for Processing by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... Fisheries Act Crab Vessels Harvesting Pacific Cod for Processing by the Inshore Component in the Central... directed fishing for Pacific cod by non- American Fisheries Act (AFA) crab vessels that are subject to... sideboard limit established for non-AFA crab vessels harvesting Pacific cod for processing by the inshore...

  10. The acute phase response of cod (Gadus morhua L.): expression of immune response genes.

    PubMed

    Audunsdottir, Sigridur S; Magnadottir, Bergljot; Gisladottir, Berglind; Jonsson, Zophonias O; Bragason, Birkir Th

    2012-02-01

    An acute phase response (APR) was experimentally induced in Atlantic cod (Gadus morhua L.) by intramuscular injection of turpentine oil. The change in the expression of immune related genes was monitored in the anterior kidney and the spleen over a period of 7 days. The genes examined were two types of pentraxins, apolipoprotein A1 (ApoA-I), the complement component C3, interleukin-1β (IL-1β), transferrin, cathelicidin, and hepcidin. All genes were constitutively expressed in both organs and their expression amplified by the turpentine injection. A pattern of response was observed both with respect to the organ preference and to the timing of a maximum response. The increased gene expression of the pentraxins, ApoA-I and C3 was restricted to the anterior kidney, the gene expression of IL-1β, cathelicidin, and transferrin increased in both organs, while hepcidin gene expression was only significantly increased in the spleen. The pentraxins and ApoA-I appear to be early mediators of APR in cod, possibly stimulating C3 and IL-1β response, while the antimicrobial peptides may play a minor role. The increase in transferrin gene expression in both organs, and apparent indifference to cortisol release associated with the turpentine injection, suggests that this could be a typical acute phase protein in cod.

  11. Analysis of the Cape Cod tracer data

    USGS Publications Warehouse

    Ezzedine, Souheil; Rubin, Yoram

    1997-01-01

    An analysis of the Cape Cod test was performed using several first- and higher-order theoretical models. We compare conditional and unconditional solutions of the transport equation and employ them for analysis of the experimental data. We consider spatial moments, mass breakthrough curves, and the distribution of the solute mass in space. The concentration measurements were also analyzed using theoretical models for the expected value and variance of concentration. The theoretical models we employed are based on the spatial correlation structure of the conductivity field, without any fitting of parameters to the tracer data, and hence we can test the predictive power of the theories tested. The effects of recharge on macrodispersion are investigated, and it is shown that recharge provides a reasonable explanation for the enhanced lateral spread of the Cape Cod plume. The compendium of the experimental results presented here is useful for testing of theoretical and numerical models.

  12. Prehistoric versus modern Baltic Sea cod fisheries: selectivity across the millennia

    PubMed Central

    Limburg, Karin E; Walther, Yvonne; Hong, Bongghi; Olson, Carina; Storå, Jan

    2008-01-01

    Combining Stone Age and modern data provides unique insights for management, extending beyond contemporary problems and shifting baselines. Using fish chronometric parts, we compared demographic characteristics of exploited cod populations from the Neolithic Period (4500 BP) to the modern highly exploited fishery in the central Baltic Sea. We found that Neolithic cod were larger (mean 56.4 cm, 95% confidence interval (CI)±0.9) than modern fish (weighted mean length in catch =49.5±0.2 cm in 1995, 48.2±0.2 cm in 2003), and older (mean ages =4.7±0.11, 3.1±0.02 and 3.6±0.02 years for Neolithic, 1995, and 2003 fisheries, respectively). Fishery-independent surveys in 1995 and 2003 show that mean sizes in the stock are 16–17 cm smaller than reflected in the fishery, and mean ages approximately 1–1.5 years younger. Modelled von Bertalanffy growth and back-calculated lengths indicated that Neolithic cod grew to smaller asymptotic lengths, but were larger at younger ages, implying rapid early growth. Very small Neolithic cod were absent and large individuals were rare as in modern times. This could be owing to selective harvests, the absence of small and large fish in the area or a combination. Comparing modern and prehistoric times, fishery selection is evident, but apparently not as great as in the North Atlantic proper. PMID:18755680

  13. Forecasting the Major Influences of Predation and Environment on Cod Recovery in the Northern Gulf of St. Lawrence

    PubMed Central

    Bousquet, Nicolas; Chassot, Emmanuel; Duplisea, Daniel E.; Hammill, Mike O.

    2014-01-01

    The northern Gulf of St. Lawrence (NGSL) stock of Atlantic cod (Gadus morhua), historically the second largest cod population in the Western Atlantic, has known a severe collapse during the early 1990 s and is currently considered as endangered by the Committee on the Status of Endangered Wildlife in Canada. As for many fish populations over the world which are currently being heavily exploited or overfished, urgent management actions in the form of recovery plans are needed for restoring this stock to sustainable levels. Stochastic projections based on a statistical population model incorporating predation were conducted over a period of 30 years (2010–2040) to assess the expected outcomes of alternative fishing strategies on the stock recovery under different scenarios of harp seal (Pagophilus groenlandicus) abundance and environmental conditions. This sensitivity study shows that water temperature is key in the rebuilding of the NGSL cod stock. Model projections suggest that maintaining the current management practice under cooler water temperatures is likely to maintain the species in an endangered status. Under current or warmer conditions in the Gulf of St. Lawrence, partial recovery might only be achieved by significant reductions in both fishing and predation pressure. In the medium-term, a management strategy that reduces catch could be favoured over a complete moratorium so as to minimize socio-economic impacts on the industry. PMID:24523852

  14. Forecasting the major influences of predation and environment on cod recovery in the northern Gulf of St. Lawrence.

    PubMed

    Bousquet, Nicolas; Chassot, Emmanuel; Duplisea, Daniel E; Hammill, Mike O

    2014-01-01

    The northern Gulf of St. Lawrence (NGSL) stock of Atlantic cod (Gadus morhua), historically the second largest cod population in the Western Atlantic, has known a severe collapse during the early 1990 s and is currently considered as endangered by the Committee on the Status of Endangered Wildlife in Canada. As for many fish populations over the world which are currently being heavily exploited or overfished, urgent management actions in the form of recovery plans are needed for restoring this stock to sustainable levels. Stochastic projections based on a statistical population model incorporating predation were conducted over a period of 30 years (2010-2040) to assess the expected outcomes of alternative fishing strategies on the stock recovery under different scenarios of harp seal (Pagophilus groenlandicus) abundance and environmental conditions. This sensitivity study shows that water temperature is key in the rebuilding of the NGSL cod stock. Model projections suggest that maintaining the current management practice under cooler water temperatures is likely to maintain the species in an endangered status. Under current or warmer conditions in the Gulf of St. Lawrence, partial recovery might only be achieved by significant reductions in both fishing and predation pressure. In the medium-term, a management strategy that reduces catch could be favoured over a complete moratorium so as to minimize socio-economic impacts on the industry.

  15. Evidence of segregated spawning in a single marine fish stock: Sympatric divergence of ecotypes in icelandic cod?

    USGS Publications Warehouse

    Grabowski, T.B.; Thorsteinsson, Vilhjalmur; McAdam, B.J.; Marteinsdottir, G.

    2011-01-01

    There is increasing recognition of intraspecific diversity and population structure within marine fish species, yet there is little direct evidence of the isolating mechanisms that maintain it or documentation of its ecological extent. We analyzed depth and temperature histories collected by electronic data storage tags retrieved from 104 Atlantic cod at liberty ???1 year to evaluate a possible isolating mechanisms maintaining population structure within the Icelandic cod stock. This stock consists of two distinct behavioral types, resident coastal cod and migratory frontal cod, each occurring within two geographically distinct populations. Despite being captured together on the same spawning grounds, we show the behavioral types seem reproductively isolated by fine-scale differences in spawning habitat selection, primarily depth. Additionally, the different groups occupied distinct seasonal thermal and bathymetric niches that generally demonstrated low levels of overlap throughout the year. Our results indicate that isolating mechanisms, such as differential habitat selection during spawning, might contribute to maintaining diversity and fine-scale population structure in broadcast-spawning marine fishes.

  16. 75 FR 48990 - Cape Cod National Seashore; South Wellfleet, MA; Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR... hereby given in accordance with the Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770, 5 U.S.C. App 1, Section 10) of a meeting of the Cape Cod National Seashore Advisory Commission. DATES: The...

  17. 9 CFR 2.79 - C.O.D. shipments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false C.O.D. shipments. 2.79 Section 2.79... WELFARE REGULATIONS Records § 2.79 C.O.D. shipments. (a) No carrier or intermediate handler shall accept any animal for transportation, in commerce, upon any C.O.D. or other basis where any money is to...

  18. 9 CFR 2.79 - C.O.D. shipments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false C.O.D. shipments. 2.79 Section 2.79... WELFARE REGULATIONS Records § 2.79 C.O.D. shipments. (a) No carrier or intermediate handler shall accept any animal for transportation, in commerce, upon any C.O.D. or other basis where any money is to...

  19. Effect of White Charcoal on COD Reduction in Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Pijarn, Nuchanaporn; Butsee, Manipa; Buakul, Kanokwan; Seng, Hasan; Sribuarai, Tinnphat; Phonprasert, Pongtep; Taneeto, Kla; Atthameth, Prasertsil

    2017-06-01

    The objective of this study is to compare the COD reduction in wastewater between using coconut shell and coconut spathe white charcoal from Khlong Wat NongPra-Ong, Krathumbaen, SamutSakhon province, Thailand. The waste water samples were collected using composite sampling method. The experimental section can be divided into 2 parts. The first part was study the optimum of COD adsorption time using both white charcoals. The second part was study the optimum amount of white charcoal for chemical oxygen demand (COD) reduction. The pre-treatment of wastewater was examined in parameters include temperature, alkalinity (pH), conductivity, turbidity, suspended solid (SS), total dissolved solid (TDS), and COD. The results show that both white charcoals can reduce COD of wastewater. The pH of pre-treatment wastewater had pH 9 but post-treatment wastewaters using both white charcoals have pH 8. The COD of pre-treatment wastewater had COD as 258 mg/L but post-treatment wastewater using coconut shell white charcoal had COD steady at 40 mg/L in 30 min and the amount of white charcoals 4 g. The COD of post-treatment wastewater using coconut spathe white charcoal had COD steady at 71 mg/L in 30 min and the amount of white charcoals 4 g. Therefore comparison of COD reduction between coconut shell white charcoal versus coconut spathe white charcoal found that the coconut shell white charcoal had efficiency for COD reduction better than coconut spathe white charcoal.

  20. 1H NMR metabolic profiling of cod (Gadus morhua) larvae: potential effects of temperature and diet composition during early developmental stages

    PubMed Central

    Chauton, Matilde Skogen; Galloway, Trina Falck; Kjørsvik, Elin; Størseth, Trond Røvik; Puvanendran, Velmurugu; van der Meeren, Terje; Karlsen, Ørjan; Rønnestad, Ivar; Hamre, Kristin

    2015-01-01

    ABSTRACT Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry where the potential is not yet realized. Research has revealed that a major bottleneck to successful farming of cod is poor quality of the larvae and juveniles. A large research program was designed to increase our understanding of how environmental factors such as temperature and nutrition affects cod larvae development. Data on larvae growth and development were used together with nuclear magnetic resonance. The NMR data indicated that the temperature influenced the metabolome of the larvae; differences were related to osmolytes such as betaine/TMAO, the amino acid taurine, and creatine and lactate which reflect muscle activity. The larvae were fed Artemia from stage 2, and this was probably reflected in a high taurine content of older larvae. Larvae fed with copepods in the nutrition experiment also displayed a high taurine content, together with higher creatine and betaine/TMAO content. Data on the cod larvae metabolome should be coupled to data on gene expression, in order to identify events which are regulated on the genetic level versus regulation resulting from temperature or nutrition during development, to fully understand how the environment affects larval development. PMID:26545964

  1. Comment on “Slow adaptation in the face of rapid warming leads to collapse of the Gulf of Maine cod fishery”

    NASA Astrophysics Data System (ADS)

    Palmer, Michael C.; Deroba, Jonathan J.; Legault, Christopher M.; Brooks, Elizabeth N.

    2016-04-01

    Pershing et al. (Reports, 13 November, p. 809) concluded that failure to account for temperature in the assessment and management of Gulf of Maine Atlantic cod caused overfishing. We argue that the “extra mortality” calculation driving this conclusion is an artifact. Environmental factors affect all stocks, but attribution of additional mortality to temperature alone by Pershing et al. is unsupported by the data.

  2. Ecological Condition of Coastal Ocean Waters Along the U.S. Mid-Atlantic Bight: 2006

    EPA Science Inventory

    This report presents the results of an assessment of ecological condition in coastal-ocean waters of the U.S. mid-Atlantic Bight (MAB), along the U.S. continental shelf from Cape Cod, MA and Nantucket Shoals to the northeast to Cape Hatteras to the south, based on sampling conduc...

  3. ECOLOGICAL CONDITION OF THE ESTUARIES OF THE ATLANTIC AND GULF COASTS OF THE UNITED STATES.

    EPA Science Inventory

    Monitoring the estuaries of the Atlantic and Gulf of Mexico coastlines from Cape Cod, MA to Brownsville, TX was performed annually from 1990-1997 to assess ecological conditions on a regional basis for four biogeographic provinces. These province estimates - Virginian, Carolinia...

  4. Ecological Condition of Coastal Ocean Waters Along the U.S. Mid-Atlantic Bight: 2006

    EPA Science Inventory

    This report presents the results of an assessment of ecological condition in coastal-ocean waters of the U.S. mid-Atlantic Bight (MAB), along the U.S. continental shelf from Cape Cod, MA and Nantucket Shoals to the northeast to Cape Hatteras to the south, based on sampling conduc...

  5. 9 CFR 2.79 - C.O.D. shipments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false C.O.D. shipments. 2.79 Section 2.79 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Records § 2.79 C.O.D. shipments. (a) No carrier or intermediate handler shall accept...

  6. 9 CFR 2.79 - C.O.D. shipments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false C.O.D. shipments. 2.79 Section 2.79 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Records § 2.79 C.O.D. shipments. (a) No carrier or intermediate handler shall accept...

  7. 9 CFR 2.79 - C.O.D. shipments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false C.O.D. shipments. 2.79 Section 2.79 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Records § 2.79 C.O.D. shipments. (a) No carrier or intermediate handler shall accept...

  8. Could Seals Prevent Cod Recovery in the Baltic Sea?

    PubMed Central

    MacKenzie, Brian R.; Eero, Margit; Ojaveer, Henn

    2011-01-01

    Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which they were formerly productive and supported sustainable fisheries. Here we investigate how a cod (Gadus morhua) population in the Baltic Sea whose biomass was reduced due to a combination of high exploitation and deteriorating environmental conditions might recover and develop in the 21st century in an ecosystem that likely will change due to both the already started recovery of a cod predator, the grey seal Halichoerus grypus, and projected climate impacts. Simulation modelling, assuming increased seal predation, fishing levels consistent with management plan targets and stable salinity, shows that the cod population could reach high levels well above the long-term average. Scenarios with similar seal and fishing levels but with 15% lower salinity suggest that the Baltic will still be able to support a cod population which can sustain a fishery, but biomass and yields will be lower. At present knowledge of cod and seal interactions, seal predation was found to have much lower impact on cod recovery, compared to the effects of exploitation and salinity. These results suggest that dual management objectives (recovery of both seal and cod populations) are realistic but success in achieving these goals will also depend on how climate change affects cod recruitment. PMID:21573062

  9. 45. CAPE COD AIR STATION PAVE PAWS FACILITY BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. CAPE COD AIR STATION PAVE PAWS FACILITY - BUILDING ELEVATION VIEW WITH BUILDING METAL SIDING BEING APPLIED ON "A" FACE (LEFT) AND "B" FACE (RIGHT). NOTE THAT NORTH IS GENERALLY TO RIGHT OF VIEW. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  10. 43. CAPE COD AIR STATION PAVE PAWS FACILITY WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. CAPE COD AIR STATION PAVE PAWS FACILITY - WITH BUILDING METAL SIDING BEING APPLIED ON "C" FACE (RIGHT) AND "B" FACE BEING PREPARED FOR INSTALLATION. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  11. 46. CAPE COD AIR STATION PAVE PAWS FACILITY BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. CAPE COD AIR STATION PAVE PAWS FACILITY - BUILDING ELEVATION VIEW WITH ALL METAL SIDING INSTALLED AND WITH EMITTER/ANTENNA ARRAY SYSTEM NEARING OCMPLETION ON "B" FACE (RIGHT). VIEW ALSO SHOWS TRAVELING "CLEANING" SYSTEM ON "B" FACE - NOW REMOVED. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  12. 42. CAPE COD AIR STATION PAVE PAWS FACILITY SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. CAPE COD AIR STATION PAVE PAWS FACILITY - SHOWING BUILDING "RED IRON" STEEL STRUCTURE AT 46T DAY OF STEEL CONSTRUCTION. "BUILDING TOPPED OFF, 7 JULY, 1974. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  13. 47. CAPE COD AIR STATION PAVE PAWS FACILITY AERIAL VIEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. CAPE COD AIR STATION PAVE PAWS FACILITY AERIAL VIEW OF "A" FACE (LEFT) WITH CLEANING SYSTEM INSTALLED (NOW REMOVED) AND "B" FACE (RIGHT) WITH CONSTRUCTION CRANE IN USE. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  14. Could seals prevent cod recovery in the Baltic Sea?

    PubMed

    MacKenzie, Brian R; Eero, Margit; Ojaveer, Henn

    2011-05-09

    Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which they were formerly productive and supported sustainable fisheries. Here we investigate how a cod (Gadus morhua) population in the Baltic Sea whose biomass was reduced due to a combination of high exploitation and deteriorating environmental conditions might recover and develop in the 21st century in an ecosystem that likely will change due to both the already started recovery of a cod predator, the grey seal Halichoerus grypus, and projected climate impacts. Simulation modelling, assuming increased seal predation, fishing levels consistent with management plan targets and stable salinity, shows that the cod population could reach high levels well above the long-term average. Scenarios with similar seal and fishing levels but with 15% lower salinity suggest that the Baltic will still be able to support a cod population which can sustain a fishery, but biomass and yields will be lower. At present knowledge of cod and seal interactions, seal predation was found to have much lower impact on cod recovery, compared to the effects of exploitation and salinity. These results suggest that dual management objectives (recovery of both seal and cod populations) are realistic but success in achieving these goals will also depend on how climate change affects cod recruitment.

  15. COD fractionation and biological treatability of mixed industrial wastewaters.

    PubMed

    Fall, C; Millán-Lagunas, E; Bâ, K M; Gallego-Alarcón, I; García-Pulido, D; Díaz-Delgado, C; Solís-Morelos, C

    2012-12-30

    This study was conducted at a centralized wastewater treatment plant that receives discharges from nearly 160 industries. The chemical oxygen demand (COD) was fractionated for two objectives: delineation of the limits of the activated sludge process being used at the plant, and evaluation of the potential environmental impact of the treated effluent. Physico-chemical analyses, respirometric and biodegradation tests, as well as COD fractionation were carried out. Molasses-wastewaters were determined to be the major contribution to the plant. The influent was dark brown in color, with a relatively high content of both organics (2503 mg/L COD) and salts (5459 μS/cm conductivity), but a low biochemical oxygen demand (568 mg/L BOD(5)) and BOD(5)/COD ratio (0.24). The degradability of the organics was limited by the high content of inert soluble COD (S(I)). The COD fractionation pattern was 40-20-40% for S(I), X(I) (inerts) and S(H) (soluble hydrolyzable), respectively. More than 90% BOD(5) removal was obtained, which was sufficient for the plant to meet the national Standards. However, the effluent discharged into the river was intensely colored and polluted (>1000 mg/L COD, >5000 μS/cm), emphasizing the need for legislation regulating COD, color and salinity, and for upgraded treatment methods worldwide for molasses wastewaters.

  16. EPA Cape Cod 208 Plan 2015 Update Approval Letter

    EPA Pesticide Factsheets

    EPA approval letter re: certification by the Governor of MA that the Cape Cod WQM Plan Update is consistent with CWA section 208(b)(3) & accepted the Commonwealth’s reaffirmation of the existing designations of Cape Cod Towns as waste management agencies.

  17. 33 CFR 117.589 - Cape Cod Canal.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Cape Cod Canal. 117.589 Section 117.589 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.589 Cape Cod Canal. The draw...

  18. 33 CFR 117.589 - Cape Cod Canal.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Cape Cod Canal. 117.589 Section 117.589 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.589 Cape Cod Canal. The draw...

  19. 33 CFR 117.589 - Cape Cod Canal.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Cape Cod Canal. 117.589 Section 117.589 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.589 Cape Cod Canal. The draw...

  20. 33 CFR 117.589 - Cape Cod Canal.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Cape Cod Canal. 117.589 Section 117.589 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.589 Cape Cod Canal. The draw...

  1. 17. CAPE COD AIR STATION PAVE PAWS FACILITY AERIAL VIEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. CAPE COD AIR STATION PAVE PAWS FACILITY AERIAL VIEW WITH PROJECT NEARING COMPLETION. VIEW SHOWS "A" FACE (LEFT) AND "B" FACE OF RADAR ARRAY SYSTEM. NOTE THAT NORTH IS GENERALLY TO RIGHT OF VIEW. - Cape Cod Air Station, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  2. Fenton treatment of landfill leachate under different COD loading factors.

    PubMed

    Singh, Shrawan K; Tang, Walter Z; Tachiev, Georgio

    2013-10-01

    The application of Fenton treatment technology for treatment of landfill leachate greatly depends on the optimum Fenton operating conditions for a specific leachate. Determining optimum Fenton conditions requires multiple experiments using variable reaction parameters (pH, temperature, and H2O2 and Fe(2+) doses) and previous researches show a wide range of optimal operating conditions. In this study, the applicability of the dimensionless loading factor (LCOD), which is defined as the initial COD (COD0) of leachate with respect to available O2 for oxidation, was examined to derive optimum Fenton oxidant dose using reduced set of experiments. The Fenton experiments were conducted using leachates with three different COD0 concentrations, 1092, 546, and 273mgL(-1), LCOD in the range of 0.25-1.0, and H2O2/Fe(2+) 1.8 (w/w). The experimental data were analyzed to determine the correlation between the LCOD factor and selected feasibility parameters, amongst which were: (i) the COD removal kinetics, (ii) the total COD removal, (iii) the usability of H2O2 with respect to COD removal, (iv) leachate biodegradability, and (v) treatment cost incurred by chemical usage. The experimental COD removal with respect to the amount of O2 supplied by H2O2 was compared with respect to the optimum COD removal efficiency by the equation: η(FP(optimum)=0.733L(COD)-0.182 as developed by Singh and Tang (2013) and a LCOD of 0.75 was determined to be the optimum L(COD) for leachate treatment.

  3. COD and nitrogen removal and microbial communities in a novel waterfall biofilm reactor operated at different COD/TN ratios.

    PubMed

    Wang, Siyao; Pu, Yuewu; Wei, Cheng

    2017-01-28

    The aim of this study was to characterize the pollutant removal efficiency and the microbial communities that arose in a newly designed waterfall biofilm reactor (WFBR) at different chemical oxygen demand/total nitrogen (COD/TN) ratios. The reactor was operated continuously for 28 days at different COD/TN ratios, and its efficiency was evaluated. Results showed that as the thickness of the biofilm increased, the structure of the biofilm encouraged anaerobic-aerobic, anoxic-anaerobic, and fully anaerobic conditions in one reactor. The COD/TN ratios used had a significant effect on the removal of COD and nitrogen components. At a COD/TN ratio of 14, the ammonium nitrogen removal efficiency reached its highest value (99%), but the COD removal efficiency remained at approximately 90%. High-throughput sequencing revealed that the highest community diversity and richness were seen at a COD/TN ratio of 18, and the major phyla were Proteobacteria (average abundance of 47%), Actinobacteria (24%), and Bacteroidetes (13%). As the COD/TN ratios increased from 7 to 18, the abundance of Proteobacteria gradually increased from 25% to 68%. These results could provide important guidance for the design of new wastewater treatment systems and also enrich our theoretical understanding of microbial ecology.

  4. Seasonal distribution and abundance of fishes and decapod crustaceans in a Cape Cod estuary

    USGS Publications Warehouse

    Able, K.W.; Fahay, M.P.; Heck, K.L.; Roman, C.T.; Lazzari, M.A.; Kaiser, S.C.

    2002-01-01

    Sampling in several habitat types (sand/mud, eelgrass, sand, gravel, macroalgae/mud) during all seasons with a variety of gears in Nauset Marsh, Massachusetts during 1985-1987 found a fauna consisting of 35 fish and 10 decapod crustacean species. Although most of the abundant species were found in several habitat types, species richness and habitat use appeared to be highest for vegetated habitats (eelgrass, macroalgae). The fishes and decapods were numerically dominated by cold-water taxa; however, numerous fish species, represented by rare individuals of predominantly southern forms, enriched the fauna. Species composition of Nauset Marsh could be distinguished from estuaries south of Cape Cod and even from the south shore of the cape. Both fishes and decapods were most abundant during the summer, apparently due to the contributions from spring and summer spawning in the estuary and the adjacent Atlantic Ocean. The location of Nauset Marsh and other estuaries on Cape Cod provide a unique opportunity to evaluate the importance of this region as a faunal boundary to estuarine species.

  5. Dynamics of coastal cod populations: intra- and intercohort density dependence and stochastic processes

    PubMed Central

    Stenseth, N. C.; rnstad, O. N. Bj; Falck, W.; Fromentin, J.-M.; ter, J. Gj s; Gray, J. S.

    1999-01-01

    Skagerrak populations of Atlantic cod (Gadus morhua L.) have been surveyed at several fixed stations since 1919. These coastal populations consist of local stocks with a low age of maturity and a short life span. We investigated 60 time-series of 0-group juveniles (i.e. young of the year) sampled annually from 1945 to 1994. An age-structured model was developed which incorporates asymmetrical interactions between the juvenile cohorts (0-group and 1-group; i.e. one-year-old juveniles) and stochastic reproduction. The model was expressed in delay coordinates in order to estimate model parameters directly from the time-series and thereby test the model predictions. The autocovariance structure of the time-series was consistent with the delay coordinates model superimposed upon a long-term trend. The model illustrates how both regulatory (density-dependent) and disruptive (stochastic) forces are crucial in shaping the dynamics of the coastal cod populations. The age-structured life cycle acts to resonance the stochasticity inherent in the recruitment process.

  6. Temporal trends of contaminants in cod from Icelandic waters.

    PubMed

    Sturludottir, Erla; Gunnlaugsdottir, Helga; Jorundsdottir, Hronn O; Magnusdottir, Elin V; Olafsdottir, Kristin; Stefansson, Gunnar

    2014-04-01

    Contaminants have been analyzed in cod (Gadus morhua) since 1990 as part of the national monitoring program for the environmental conditions in the sea around Iceland. The aim of this study was to determine the temporal trends of persistent organic pollutants (POPs: polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl dichloroethene (p,p'-DDE), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), chlordanes (CHLs) and toxaphenes (Tox)) and trace elements (As, Cd, Cu, Hg, Pb, Se and Zn) in cod over the last two decades at two different locations in the Arctic Ocean north of Iceland. The relationship between the contaminant concentrations and biological covariates was also determined. All of the POPs showed decreasing trends but the trace elements showed no clear signs of trend except arsenic which showed an increasing trend and zinc which showed a decreasing trend. The concentration of the POPs were lower or similar in the Icelandic cod compared to cod sampled in Norway, the Barents Sea and in the Baltic Sea, except for HCB which was higher in the Icelandic cod compared to the Norwegian cod. The concentration of the trace elements As, Cu, Hg and Zn were similar in the Icelandic cod compared to cod sampled in Norway and Greenland but the concentration of Cd was higher in the Icelandic cod. The inclusion of the biological covariates was found to be important for the statistical analysis. The POPs had a positive relationship with liver fat content but negative relationship with liver weight. The trace elements had a negative relationship with liver fat and liver weight except As which had positive relationship with liver weight. Only positive relationships were observed between the contaminant concentrations and length.

  7. EAARL topography: Cape Cod National Seashore

    USGS Publications Warehouse

    Brock, John C.; Wright, C. Wayne; Patterson, Matt; Nayegandhi, Amar; Travers, Laurinda J.

    2007-01-01

    This Web site contains 90 Lidar-derived bare earth topography maps and GIS files for the Cape Cod National Seashore. These Lidar-derived topography maps were produced as a collaborative effort between the U.S. Geological Survey (USGS) Florida Integrated Science Center (FISC) St. Petersburg, Florida, the National Park Service (NPS), Northeast Coastal and Barrier Network, Inventory and Monitoring Program, and the National Aeronautics and Space Administration (NASA) Wallops Flight Facility. One objective of this research is to create techniques to survey coral reefs and barrier islands for the purposes of geomorphic change studies, habitat mapping, ecological monitoring, change detection, and event assessment. As part of this project, data from an innovative instrument under development at the NASA Wallops Flight Facility, the NASA Experimental Airborne Advanced Research Lidar (EAARL) are being used. This sensor has the potential to make significant contributions in this realm for measuring subaerial and submarine topography wthin cross-environment surveys. High spectral resolution, water-column correction, and low costs were found to be key factors in providing accurate and affordable imagery to coastal resource managers.

  8. The COD Model: Simulating Workgroup Performance

    NASA Astrophysics Data System (ADS)

    Biggiero, Lucio; Sevi, Enrico

    Though the question of the determinants of workgroup performance is one of the most central in organization science, precise theoretical frameworks and formal demonstrations are still missing. In order to fill in this gap the COD agent-based simulation model is here presented and used to study the effects of task interdependence and bounded rationality on workgroup performance. The first relevant finding is an algorithmic demonstration of the ordering of interdependencies in terms of complexity, showing that the parallel mode is the most simplex, followed by the sequential and then by the reciprocal. This result is far from being new in organization science, but what is remarkable is that now it has the strength of an algorithmic demonstration instead of being based on the authoritativeness of some scholar or on some episodic empirical finding. The second important result is that the progressive introduction of realistic limits to agents' rationality dramatically reduces workgroup performance and addresses to a rather interesting result: when agents' rationality is severely bounded simple norms work better than complex norms. The third main finding is that when the complexity of interdependence is high, then the appropriate coordination mechanism is agents' direct and active collaboration, which means teamwork.

  9. Water distribution in brine salted cod (Gadus morhua) and salmon (Salmo salar): a low-field 1H NMR study.

    PubMed

    Aursand, Ida G; Gallart-Jornet, Lorena; Erikson, Ulf; Axelson, David E; Rustad, Turid

    2008-08-13

    Low-field (LF) (1)H NMR T 2 relaxation measurements were used to study changes in water distribution in lean (Atlantic cod) and fatty (Atlantic salmon) fish during salting in 15% NaCl and 25% NaCl brines. The NMR data were treated by PCA, continuous distribution analysis, and biexponential fitting and compared with physicochemical data. Two main water pools were observed in unsalted fish, T 21, with relaxation times in the range 20-100 ms, and T 22, with relaxation times in the range 100-300 ms. Pronounced changes in T 2 relaxation data were observed during salting, revealing changes in the water properties. Salting in 15% brine lead to a shift toward longer relaxation times, reflecting increased water mobility, whereas, salting in saturated brines had the opposite effect. Water mobility changes were observed earlier in the salting process for cod compared to salmon. Good linear correlations ( F

  10. Spatial variance of mobile aquatic organisms: capelin and cod in Newfoundland coastal waters

    PubMed Central

    Horne, J. K.; Schneider, D. C.

    1997-01-01

    Spatial variance in the distribution of aquatic mobile organisms differs from that of passive tracers such as phytoplankton or water temperature. On average, spatial variance of phytoplankton scales with sample unit as $L^2$ or equivalently with frequency as $f^{-2}$. Limited evidence suggests that spatial variance in the distribution of mobile organisms is concentrated at relatively small scales, with little increase over larger scales: spatial variance scales as $f^{-1}$ or less. We investigated whether spatial variance in distributions of a mobile predator, Atlantic cod (Gadus morhua), and a schooling prey, capelin (Mallotus villosus), also scale with frequency as $f^{-1}$. Acoustic surveys showed that at short time scales spatial variance in cod and capelin densities, as measured by spectral density, peaked at various scales ranging from 20 m to 10 km. At longer time scales, spatial variance of cod scaled as $f^{-1.08}$ at resolutions finer than 90 m, while scaling as $f^{-0.18}$ at coarser scales. Spatial variance of capelin scaled as $f^{-1.1}$ at resolutions finer than 400 m, while scaling as $f^{-0.21}$ at coarser scales. Spatial variance plots of krill and marine birds showed similar transitions from shallow to steep scaling. Shoaling, schooling and the aggregative response by predators to concentrations of prey were three processes hypothesized to influence spatial variance in distributions of mobile organisms. Numerical experiments showed that shoaling injects variance at large to intermediate scales, resulting in scalings flatter than $f^{-1}$. Additional experiments showed that schooling produces a transition from shallow to steep scaling as frequency increases. Spatial variance patterns in cod density were not due to aggregative responses by the predator to concentrations of capelin: there was no association, on average, at resolution scales from 20 m to 10 km. Exponent values for aquatic or terrestrial mobile organisms are predicted to be

  11. Cod Fractions In Mechanical-Biological Wastewater Treatment Plant

    NASA Astrophysics Data System (ADS)

    Płuciennik-Koropczuk, Ewelina; Jakubaszek, Anita; Myszograj, Sylwia; Uszakiewicz, Sylwia

    2017-03-01

    The paper presents results of studies concerning the designation of COD fraction in the raw, mechanically treated and biologically treated wastewater. The test object was a wastewater treatment plant with the output of over 20,000 PE. The results were compared with data received in the ASM models. During investigation following fractions of COD were determined: dissolved non-biodegradable SI, dissolved easily biodegradable SS, in organic suspension slowly degradable XS and in organic suspension non-biodegradable XI. Methodology for determining the COD fraction was based on the guidelines ATV-A 131. The real percentage of each fraction in total COD in raw wastewater are different from data received in ASM models.

  12. Monitoring the desalting process of cod using dielectric spectroscopy.

    PubMed

    De los Reyes, Ruth; Balbastre, Juan V; Andrés, Ana; Fito, Pedro; De los Reyes, Elias

    2009-01-01

    The desalted cod industry needs a suitable and reliable control system to check the desalting point of cod in order to provide a safe and high-quality product. The growth of the industries that are interested in a non-contacting, real-time control, encourages the development of new methods based on low-power radiation, such as dielectric spectroscopy. These techniques use the modification of wave parameters at some specific frequencies to provide information of the compositional characteristics of foods. In this work, cod parallelepipeds were desalted at 5 degrees C by immersing them in distilled water for different desalting times (15 and 30 minutes and 1, 2, 4, 6, 8, 12, 24 and 48 hours). Dielectric Spectroscopy studies have been performed on cod samples in the frequency range 200 MHz-20 GHz. The dielectric properties were measured using a coaxial probe (Agilent 85070E) connected to a Network Analyzer (Agilent E8362B) immediately after removing the cod samples from their desalting solutions. After desalting, the cod samples were separated from their desalting solutions and kept in repose for 24 h at 5 degrees C after which some of their physical properties were measured. This experimental procedure ensures that those properties have already reached their final values. Good correlations were found between the quality properties of the cod samples (a(w), Xw, Z(NaCl) and xNaCl) after 24 h and their loss factor (epsilon") measured at 10 GHz just before leaving them in repose, showing the feasibility of an in-line control system for cod desalting process at that frequency.

  13. Interaction between submicron COD crystals and renal epithelial cells

    PubMed Central

    Peng, Hua; Ouyang, Jian-Ming; Yao, Xiu-Qiong; Yang, Ru-E

    2012-01-01

    Objectives This study aims to investigate the adhesion characteristics between submicron calcium oxalate dihydrate (COD) with a size of 150 ± 50 nm and African green monkey kidney epithelial cells (Vero cells) before and after damage, and to discuss the mechanism of kidney stone formation. Methods Vero cells were oxidatively injured by hydrogen peroxide to establish a model of injured cells. Scanning electron microscopy was used to observe Vero–COD adhesion. Inductively coupled plasma emission spectrometry was used to quantitatively measure the amount of adhered COD microcrystals. Nanoparticle size analyzer and laser scanning confocal microscopy were performed to measure the change in the zeta potential on the Vero cell surface and the change in osteopontin expression during the adhesion process, respectively. The level of cell injury was evaluated by measuring the changes in malonaldehyde content, and cell viability during the adhesion process. Results The adhesion capacity of Vero cells in the injury group to COD microcrystals was obviously stronger than that of Vero cells in the control group. After adhesion to COD, cell viability dropped, both malonaldehyde content and cell surface zeta potential increased, and the fluorescence intensity of osteopontin decreased because the osteopontin molecules were successfully covered by COD. Submicron COD further damaged the cells during the adhesion process, especially for Vero cells in the control group, leading to an elevated amount of attached microcrystals. Conclusion Submicron COD can further damage injured Vero cells during the adhesion process. The amount of attached microcrystals is proportional to the degree of cell damage. The increased amount of microcrystals that adhered to the injured epithelial cells plays an important role in the formation of early-stage kidney stones. PMID:22973095

  14. [Experimental Conditions and Reliability Analysis of Results of COD components].

    PubMed

    Li, Zhi-hua; Zhang, Yin; Han, Xing; Yu, Ke; Li, Ru-jia

    2015-10-01

    The present study attempts to use SF( OUR(max)/OUR(en)) instead of S(0)/X(0) as an index of optimal initial conditions for determination of COD components by means of respirometry, thereby simplifying the measuring process and the operation can be automated. Further, the ratio of COD consumed by the growth of biomass can be used for the reliability assessment of results. Experimental results show that, experimental conditions for obtaining good results as follows: (1) for samples that composed of a large amount of easily biodegradable components (e. g., synthetic wastewater made by sodium acetate), SF should be in the range of 2.8 to 5.3, and the ratio of COD consumed by growth of biomass should be less than 30%; (2) for samples that composed of both readily biodegradable and slowly biodegradable components (i. e., typical domestic wastewater), SF should be in the range of 5.8 to 6.4, and the ratio of COD consumed by growth of biomass should be less than 30%; (3) and for samples that composed of a large amount of slowly biodegradable industrial wastewater (i. e., landfill leachate), SF should be 15 or less, and the ratio of COD consumed by growth of biomass should be approximately 40%. Therefore, when respirometry is used for the determination of COD components, the optimal conditions in terms of SF increase with the complexity of carbon source.

  15. Lobster and cod benefit from small-scale northern marine protected areas: inference from an empirical before-after control-impact study.

    PubMed

    Moland, Even; Olsen, Esben Moland; Knutsen, Halvor; Garrigou, Pauline; Espeland, Sigurd Heiberg; Kleiven, Alf Ring; André, Carl; Knutsen, Jan Atle

    2013-03-07

    Marine protected areas (MPAs) are increasingly implemented as tools to conserve and manage fisheries and target species. Because there are opportunity costs to conservation, there is a need for science-based assessment of MPAs. Here, we present one of the northernmost documentations of MPA effects to date, demonstrated by a replicated before-after control-impact (BACI) approach. In 2006, MPAs were implemented along the Norwegian Skagerrak coast offering complete protection to shellfish and partial protection to fish. By 2010, European lobster (Homarus gammarus) catch-per-unit-effort (CPUE) had increased by 245 per cent in MPAs, whereas CPUE in control areas had increased by 87 per cent. Mean size of lobsters increased by 13 per cent in MPAs, whereas increase in control areas was negligible. Furthermore, MPA-responses and population development in control areas varied significantly among regions. This illustrates the importance of a replicated BACI design for reaching robust conclusions and management decisions. Partial protection of Atlantic cod (Gadus morhua) was followed by an increase in population density and body size compared with control areas. By 2010, MPA cod were on average 5 cm longer than in any of the control areas. MPAs can be useful management tools in rebuilding and conserving portions of depleted lobster populations in northern temperate waters, and even for a mobile temperate fish species such as the Atlantic cod.

  16. Lobster and cod benefit from small-scale northern marine protected areas: inference from an empirical before–after control-impact study

    PubMed Central

    Moland, Even; Olsen, Esben Moland; Knutsen, Halvor; Garrigou, Pauline; Espeland, Sigurd Heiberg; Kleiven, Alf Ring; André, Carl; Knutsen, Jan Atle

    2013-01-01

    Marine protected areas (MPAs) are increasingly implemented as tools to conserve and manage fisheries and target species. Because there are opportunity costs to conservation, there is a need for science-based assessment of MPAs. Here, we present one of the northernmost documentations of MPA effects to date, demonstrated by a replicated before–after control-impact (BACI) approach. In 2006, MPAs were implemented along the Norwegian Skagerrak coast offering complete protection to shellfish and partial protection to fish. By 2010, European lobster (Homarus gammarus) catch-per-unit-effort (CPUE) had increased by 245 per cent in MPAs, whereas CPUE in control areas had increased by 87 per cent. Mean size of lobsters increased by 13 per cent in MPAs, whereas increase in control areas was negligible. Furthermore, MPA-responses and population development in control areas varied significantly among regions. This illustrates the importance of a replicated BACI design for reaching robust conclusions and management decisions. Partial protection of Atlantic cod (Gadus morhua) was followed by an increase in population density and body size compared with control areas. By 2010, MPA cod were on average 5 cm longer than in any of the control areas. MPAs can be useful management tools in rebuilding and conserving portions of depleted lobster populations in northern temperate waters, and even for a mobile temperate fish species such as the Atlantic cod. PMID:23303544

  17. Comparison of the Northeast Arctic cod year class strength (at the age of 3+) with the SST anomalies in main spawning ground (the Norwegian Shelf Waters) by results of analysis satellite monitoring data during last years.

    NASA Astrophysics Data System (ADS)

    Vanyushin, George

    2015-04-01

    Continuous long-term database (1998-2014) on the sea surface temperature (SST) comprising results of regional satellite monitoring (the Norwegian and the Barents seas) is used to resolve several applied problems. Authors have analyzed indirect influence the SST (the NOAA satellite data) on modern cod total stock biomass (abundance of the Northeast Arctic cod at age 3+). In this study, we went on the consideration of the relationship between the SST anomalies for March-April in the main spawning ground of the cod off the Lofoten islands in the Norwegian Shelf Waters and forecasting assessment of future cod generation success and its future abundance of 3 year old. Mean monthly SST and SST anomalies are computed for the selected area on the basis of the weekly SST maps which made by using the NOAA satellites data for the period 1998-2014. Comparison of the SST anomalies in the main spawning ground with abundance of the cod year class at age 3+ shows that survival of the cod generations was inhibited on the whole as negative (below -0,1C) well as positive SST anomalies (above +1,3C) during March and April. Finally, the results indicate that poor and low middle generations of cod at age 3+ (2002, 2004, 2010) occurred in years with negative or extremely high positive the SST anomalies in the spawning area. The SST anomalies in years which were close to normal significances provide conditions for appearance middle or strong generations of cod (2001-2003, 2005-2009, 2011-2013). So, the SST and SST anomalies (by the NOAA satellite data) characterize of increase in input of warm Atlantic waters which form numerous eddies along the main stream thus creating favorable conditions for spawning and development of the cod larvae and fry and provide them with food stock, finally direct influence on forming total stock biomass of cod and helping its population forecast. Key words: satellite monitoring of SST, the Northeast Arctic cod, spawning ground, forecast of the cod year class

  18. Growth dynamics of saffron cod (Eleginus gracilis) and Arctic cod (Boreogadus saida) in the Northern Bering and Chukchi Seas

    NASA Astrophysics Data System (ADS)

    Helser, Thomas E.; Colman, Jamie R.; Anderl, Delsa M.; Kastelle, Craig R.

    2017-01-01

    Saffron cod (Eleginus gracilis) and Arctic cod (Boreogadus saida) are two circumpolar gadids that serve as critically important species responsible for energy transfer in Arctic food webs of the northern Bering and Chukchi Seas. To understand the potential effects of sea ice loss and warming temperatures on these species' basic life history, information such as growth is needed. Yet to date, limited effort has been dedicated to the study of their growth dynamics. Based on a large sample of otoliths collected in the first comprehensive ecosystem integrated survey in the northern Bering and Chukchi Seas, procedures were developed to reliably estimate age from otolith growth zones and were used to study the growth dynamics of saffron and Arctic cod. Annual growth zone assignment was validated using oxygen isotope signatures in otoliths and otolith morphology analyzed and compared between species. Saffron cod attained larger asymptotic sizes (L∞=363 mm) and achieved their maximum size at a faster rate (K=0.378) than Arctic cod (L∞=209 mm; K=0.312). For both species, regional differences in growth were found (p<0.01). Saffron cod grew to a significantly larger size at age in the northern Bering Sea when compared to the Chukchi Sea, particularly at younger ages. Arctic cod grew to smaller asymptotic size but at faster rates in the more northerly central (L∞=197 mm;K=0.324) and southern Chukchi Sea (L∞=221 mm;K=0.297) when compared to the northern Bering Sea (L∞=266 mm;K=0.171), suggesting a possible cline in growth rates with more northerly latitudes. Comparison of growth to two periods separated by 30 years indicate that both species exhibited a decline in maximum size accompanied by higher instantaneous growth rates in more recent years.

  19. Structure-function relationships in histidine-rich antimicrobial peptides from Atlantic cod.

    PubMed

    McDonald, Mark; Mannion, Michael; Pike, Damien; Lewis, Krystina; Flynn, Andrew; Brannan, Alex M; Browne, Mitchell J; Jackman, Donna; Madera, Laurence; Power Coombs, Melanie R; Hoskin, David W; Rise, Matthew L; Booth, Valerie

    2015-07-01

    Gad-1 and Gad-2 are antimicrobial peptide (AMP) sequences encoded by paralogous genes. They are rich in histidine, which suggests that their activity might be pH-dependent. We examined their structure-function relationships with a view to learning how to improve AMP therapeutic ratios. Activity assays with Gram-negative bacteria and cancer cell lines demonstrate that Gad-2 is substantially more active at slightly acidic pH than it is at neutral pH. By contrast, the activity of Gad-1 at lower pH is similar to its activity at pH7. Circular dichroism spectra indicate that the greater functional plasticity of Gad-2 correlates with a greater structural plasticity; Gad-2's percent helicity varies dramatically with altered pH and lipid environment. Interestingly, Gad-2's highest levels of helicity do not correspond to the conditions where it is most active. High resolution solution NMR structures were determined in SDS micelles at pH5, conditions that induce an intermediate level of helicity in the peptides. Gad-1 is more helical than Gad-2, with both peptides exhibiting the greatest helical tendencies in their central region and lowest helicity in their N-termini. The high resolution structures suggest that maximum activity relies on the appropriate balance between an N-terminal region with mixed hydrophobic/hydrophilic structure features and an amphipathic central and C-terminal region. Taken together with previous studies, our results suggest that to improve the therapeutic ratio of AMPs, consideration should be given to including sequential histidine-pairs, keeping the overall charge of the peptide modest, and retaining a degree of structural plasticity and imperfect amphipathicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Mortality trends of stranded marine mammals on Cape Cod and southeastern Massachusetts, USA, 2000 to 2006.

    PubMed

    Bogomolni, Andrea L; Pugliares, Katie R; Sharp, Sarah M; Patchett, Kristen; Harry, Charles T; LaRocque, Jane M; Touhey, Kathleen M; Moore, Michael

    2010-01-25

    To understand the cause of death of 405 marine mammals stranded on Cape Cod and southeastern Massachusetts between 2000 and 2006, a system for coding final diagnosis was developed and categorized as (1) disease, (2) human interaction, (3) mass-stranded with no significant findings, (4) single-stranded with no significant findings, (5) rock and/or sand ingestion, (6) predatory attack, (7) failure to thrive or dependent calf or pup, or (8) other. The cause of death for 91 animals could not be determined. For the 314 animals that could be assigned a cause of death, gross and histological pathology results and ancillary testing indicated that disease was the leading cause of mortality in the region, affecting 116/314 (37%) of cases. Human interaction, including harassment, entanglement, and vessel collision, fatally affected 31/314 (10%) of all animals. Human interaction accounted for 13/29 (45%) of all determined gray seal Halichoerus grypus mortalities. Mass strandings were most likely to occur in northeastern Cape Cod Bay; 97/106 (92%) of mass stranded animals necropsied presented with no significant pathological findings. Mass strandings were the leading cause of death in 3 of the 4 small cetacean species: 46/67 (69%) of Atlantic white-sided dolphin Lagenorhynchus acutus, 15/21 (71%) of long-finned pilot whale Globicephala melas, and 33/54 (61%) of short-beaked common dolphin Delphinus delphis. These baseline data are critical for understanding marine mammal population health and mortality trends, which in turn have significant conservation and management implications. They not only afford a better retrospective analysis of strandings, but ultimately have application for improving current and future response to live animal stranding.

  1. COD measurement based on the integrated liquid drop sensor

    NASA Astrophysics Data System (ADS)

    Qiu, Zurong; Zhang, Guoxiong; Song, Qing; Xu, Jian

    2005-02-01

    A study on Chemical Oxygen Demand (COD) measuring method is reported, in which the COD value is measured by an integrated liquid drop monitor sensor without any reagent and chemical treatment. The integrated drop sensor consists of a liquid head, an integrated fiber sensor and a capacitor sensor. The capacitor sensor is composed of a drop head and a ring electrode. As the part of the drop head, the outline of the drop will be changed during the drop forming, which result in the variation of the capacitance. The fiber sensor is composed of two fibers that are positioned into the liquid drop. The light signal goes into the liquid drop from one fiber and out from the other one. A unique fingerprint of the liquid drop can be got by the data processing. The matching between the COD value of a liquid and the codes of the fingerprints in the database are presented and discussed.

  2. COD measurements at various positions along a crack

    NASA Technical Reports Server (NTRS)

    Sharpe, W. N., Jr.; Su, X.

    1988-01-01

    Load versus crack-opening-displacement (COD) was measured at various positions along the border of a fatigue crack as it grew from a small surface crack on the edge of an aluminum specimen into a through-the-thickness crack. Displacements were measured with a laser-based interferometric system with a gage length of 70 microns and a resolution of 0.01 micron. These load-COD curves can be used to determine opening loads and thereby investigate the effect of closure on the growth of small cracks. In general, the opening loads decrease as the crack grows.

  3. H2O2_COD_EPA; MEC_acclimation

    EPA Pesticide Factsheets

    H2O2_COD_EPA: Measurements of hydrogen peroxide and COD concentrations for water samples from the MEC reactors.MEC_acclimation: raw data for current and voltage of the anode in the MEC reactor.This dataset is associated with the following publication:Sim, J., J. An, E. Elbeshbishy, R. Hodon, and H. Lee. Characterization and optimization of cathodic conditions for H2O2 synthesis in microbial electrochemical cells. Bioresource Technology. Elsevier Online, New York, NY, USA, 195: 31-36, (2015).

  4. Nitrite Interference with Soluble COD Measurements from Aerobically Treated Wastewater.

    PubMed

    Ferraz, Fernanda M; Yuan, Qiuyan

    2017-06-01

      This study aimed to determine the interference of nitrite () with soluble chemical oxygen demand (COD) measurements from the effluent of landfill leachate treated by sequencing batch reactors (SBRs). Synthetic wastewater assimilating young and old landfill leachate was used as influent for SBR1 and SBR2, respectively. A mixture of raw wastewater and landfill leachate was used as influent for SBR3. Due to the high ammonia concentration in the influent, different levels of partial nitrification were observed in all the reactors and was detected in the effluents. Theoretically, when is present in the effluent, 1 mg/L of accounts for 1.1 mg/L of COD (i.e., 1.1 mg COD/mg ) due to the oxidation of to . It was found that the value of 1.1 mg COD/mg was 3 times higher than the values obtained in the experiments with SBR1 and SBR3. In addition, the values obtained in the experiments with SBR2 were much higher than 1.1 mg COD/mg . These results suggest that the theoretical value of 1.1 mg COD/mg cannot be applied to predict the COD values caused by nitrite in the tested wastewaters. To obtain

  5. 75 FR 7205 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-18

    ... Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act Crab Vessels Catching Pacific Cod for... Fisheries Act (AFA) crab vessels catching Pacific cod for processing by the inshore component in the Western... allowance of the 2010 Pacific cod sideboard limits apportioned to non-AFA crab vessels catching Pacific cod...

  6. 75 FR 3875 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ... Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act Crab Vessels Catching Pacific Cod for... Fisheries Act (AFA) crab vessels catching Pacific cod for processing by the inshore component in the Central... allowance of the 2010 Pacific cod sideboard limits apportioned to non-AFA crab vessels catching Pacific cod...

  7. 76 FR 66196 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Harvesting Pacific...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Harvesting Pacific Cod for Processing by the Inshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels harvesting Pacific cod... to vessels harvesting Pacific cod for processing by the inshore component of the Western...

  8. 76 FR 9693 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Harvesting Pacific...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-22

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Harvesting Pacific Cod for Processing by the Inshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels harvesting Pacific cod... allowable catch (TAC) apportioned to vessels harvesting Pacific cod for processing by the inshore...

  9. 76 FR 5718 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Harvesting Pacific...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-02

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Harvesting Pacific Cod for Processing by the Inshore...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels harvesting Pacific cod... allowable catch (TAC) apportioned to vessels harvesting Pacific cod for processing by the inshore...

  10. Causes and projections of abrupt climate-driven ecosystem shifts in the North Atlantic.

    PubMed

    Beaugrand, Grégory; Edwards, Martin; Brander, Keith; Luczak, Christophe; Ibanez, Frederic

    2008-11-01

    Warming of the global climate is now unequivocal and its impact on Earth' functional units has become more apparent. Here, we show that marine ecosystems are not equally sensitive to climate change and reveal a critical thermal boundary where a small increase in temperature triggers abrupt ecosystem shifts seen across multiple trophic levels. This large-scale boundary is located in regions where abrupt ecosystem shifts have been reported in the North Atlantic sector and thereby allows us to link these shifts by a global common phenomenon. We show that these changes alter the biodiversity and carrying capacity of ecosystems and may, combined with fishing, precipitate the reduction of some stocks of Atlantic cod already severely impacted by exploitation. These findings offer a way to anticipate major ecosystem changes and to propose adaptive strategies for marine exploited resources such as cod in order to minimize social and economic consequences.

  11. Linking North Atlantic Teleconnections to Latitudinal Variability of Wave Climate Along the North American Atlantic Coast

    NASA Astrophysics Data System (ADS)

    Provancha, C.; Adams, P. N.; Hegermiller, C.; Storlazzi, C. D.

    2015-12-01

    Shoreline change via coastal erosion and accretion is largely influenced by variations in ocean wave climate. Identifying the sources of these variations is challenging because the timing of wave energy delivery varies over multiple timescales within ocean basins. We present the results of an investigation of USACE Wave Information Studies hindcast hourly wave heights, periods, and directions along the North American Atlantic coast from 1980-2012, designed to explore links between wave climate and teleconnection patterns. Trends in median and extreme significant wave heights (SWHs) demonstrate that mean monthly SWHs increased from 1 to 5 cm/yr along the roughly 3000 km reach of study area, with changes in hurricane season waves appearing to be most influential in producing the overall trends. Distributions of SWHs categorized by North Atlantic Oscillation (NAO) phase, show that positive-period NAO SWHs are greater than negative-period NAO SWHs along the entire eastern seaboard (25°N to 45°N). The most prominent wave direction off Cape Cod, MA during positive-period NAO is approximately 105°, as compared to approximately 75° during negative-period NAO. Prominent wave directions between Cape Canaveral, FL, and Savannah, GA exhibit a similar shift but during opposite phases of the NAO. The results of this analysis suggest that the atmosphere-ocean interactions associated with contrasting NAO phases can significantly change the wave climate observed offshore along the North American Atlantic coast, altering alongshore wave energy fluxes and sediment transport patterns along the coast.

  12. EPA Approves Massachusetts Plan to Protect Cape Cod Waters

    EPA Pesticide Factsheets

    EPA has formally approved an updated plan from the Commonwealth of MA that creates a robust framework for Cape Cod communities to reduce nitrogen levels that are currently harming ecological health of ponds, bays and other surface waters on the Cape.

  13. Delineation of groundwater recharge areas, western Cape Cod, Massachusetts

    USGS Publications Warehouse

    Masterson, John P.; Walter, Donald A.

    2000-01-01

    For additional information on the hydrology and geology of western Cape Cod, the reader is referred to the following reports: LeBlanc and others (1986), Barlow and Hess (1993), Masterson and others (1997a), Masterson and others (1997b), Masterson and others (1998), Ogden Environmental and Energy Services, Inc. (1998) and Jacobs Engineering Group, Inc. (1999).

  14. Arctic Climate Change: A Tale of Two Cod Species

    EPA Science Inventory

    Arctic cod play an important role in the Arctic trophic hierarchy as the consumer of primary productivity and a food source for many marine fish and mammals. Shifts in their distribution and abundance could have cascading affects in the marine environment. This paper investigates...

  15. Arctic Climate Change: A Tale of Two Cod Species

    EPA Science Inventory

    Arctic cod play an important role in the Arctic trophic hierarchy as the consumer of primary productivity and a food source for many marine fish and mammals. Shifts in their distribution and abundance could have cascading affects in the marine environment. This paper investigates...

  16. EAARL Coastal Topography–Cape Cod National Seashore, Massachusetts, 2002

    USGS Publications Warehouse

    Kranenburg, Christine; Hardy, Matthew; Nagle, David B.

    2017-01-01

    These datasets, prepared by the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center in collaboration with the National Park Service, provide lidar-derived first-surface and bare-earth topography for Cape Cod National Seashore, Massachusetts. Elevation measurements were acquired by the Experimental Advanced Airborne Research Lidar (EAARL) during October 2002.

  17. Platinum(II) 1,5-COD oxo complexes

    SciTech Connect

    Shan, H.; James, A.; Sharp, P.R.

    1998-11-02

    Three new types of platinum(II) oxo complexes--[(1,5-COD)Pt({mu}{sup 3}-O)(AuL)]{sub 2}(BF{sub 4}){sub 2} [1, L = PPh{sub 3}, PPh{sub 2}Et, PPh{sub 2}-i-Pr, P(o-tol){sub 3}, P(p-tol){sub 3}, P(p-MeOC{sub 6}H{sub 4}){sub 3}, P(p-CF{sub 3}C{sub 6}H{sub 4}){sub 3}], [(1,5-COD)Pt{l_brace}{mu}{sup 3}-O(AuL){sub 2}{r_brace}{sub 2}](BF{sub 4}){sub 2} (2), and [(1,5-COD){sub 4}Pt{sub 4}({mu}{sup 3}-O){sub 2}Cl{sub 2}]X{sub 2} (3, X = BF{sub 4}; 3a, X = CF{sub 3}SO{sub 3})--are obtained from oxo/chloro exchange reactions between (1,5-COD)PtCl{sub 2} and [(LAu){sub 3}({mu}{sup 3}-O)]BF{sub 4}. Crystals of 1 (L = PPh{sub 3}) from CDCl{sub 3} are triclinic. Crystals of 3a from CH{sub 2}Cl{sub 2}/toluene are trigonal. The structure of the cationic portion of 1 shows a planar (COD)-Pt({mu}-O){sub 2}Pt(COD) unit with slightly out-of-plane LAu{sup +} groups linearly coordinated to the oxo ligands. The structure of the cationic portion of 3a is similar and shows a slightly folded (COD)Pt({mu}-O){sub 2}Pt(COD) unit with out-of-plane [(COD)PtCl]{sup +} groups coordinated to the oxo ligands. Solutions of 3 in untreated CH{sub 2}Cl{sub 2} or CD{sub 2}Cl{sup 2} deposit crystals of [(1,5-COD){sub 4}Pt{sub 4}({mu}{sup 3}-O){sub 2}({mu}{sup 2}-OH)](BF{sub 4}){sub 3} (4) which are monoclinic. The core structure of the cationic portion of 4 shows a tetranuclear platinum cation in which the metal atoms occupy the corners of a distorted tetrahedron and two {mu}{sup 3}-oxo ligands and one {mu}{sup 2}-hydroxo ligand bridge the four platinum atoms. Reaction of 1 (L = PPh{sub 3}) with PPh{sub 3} gives OPPh{sub 3} and [(Ph{sub 3}P){sub 3}PtAuPPh{sub 3}]BF{sub 4} (5) which is also obtained from (Ph{sub 3}P){sub 4}Pt and Ph{sub 3}-PAuBF{sub 4}. Crystals of 5 from THF are monoclinic. The structure of 5 consists of an L{sub 3}Pt-AuL cation where the Au atom is linear 2-coordinate and the Pt atom is distorted square-planar 4-coordinate.

  18. Five Cape Cod Communities Receiving EPA Technical Assistance to Address Nitrogen Pollution

    EPA Pesticide Factsheets

    Fieldwork is beginning this week in the Cape Cod communities of Barnstable, Dennis, Falmouth, Mashpee and Orleans on a project that may help reduce harmful levels of nitrogen and other nutrients from flowing into Cape Cod waters.

  19. 75 FR 11129 - Mid-Atlantic Fishery Management Council; Atlantic Mackerel, Butterfish, Atlantic Bluefish, Spiny...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ...; Atlantic Mackerel, Butterfish, Atlantic Bluefish, Spiny Dogfish, Summer Flounder, Scup, Black Sea Bass... Atlantic mackerel, butterfish, Atlantic bluefish, spiny dogfish, summer flounder, scup, black sea bass... Council has been in the process of developing an Omnibus Amendment to the FMPs for Atlantic...

  20. 76 FR 61060 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Correction to Cod...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-03

    .... SUMMARY: NMFS is decreasing the Gulf of Maine and Georges Bank cod landing limit to 50 lb (22.7 kg) and 25..., 2011, decreased the GOM cod trip limit to 350 lb (158.8 kg) per DAS and the GB cod trip limit to 300 lb... consider future inseason adjustments to decrease the trip limit, or to increase differential DAS measures...

  1. Changes in Bacillus anthracis CodY regulation under host-specific environmental factor deprived conditions.

    PubMed

    Kim, Se Kye; Jung, Kyoung Hwa; Chai, Young Gyu

    2016-08-17

    Host-specific environmental factors induce changes in Bacillus anthracis gene transcription during infection. A global transcription regulator, CodY, plays a pivotal role in regulating central metabolism, biosynthesis, and virulence in B. anthracis. In this study, we utilized RNA-sequencing to assess changes in the transcriptional patterns of CodY-regulated B. anthracis genes in response to three conditions of environmental starvation: iron, CO2, or glucose deprivation. In addition, we performed chromatin immunoprecipitation on newly identified CodY-mediated genes. Environmental deprivation induced transcriptional changes in CodY-regulated genes in both wild-type and codY null strains, and both CodY-specific and environment-specific patterns were observed. In the iron-depleted condition, overexpression of iron homeostasis genes was observed independent of codY deletion; however, transcription of siderophore and amino acid biosynthesis genes was CodY dependent. Although CodY has a significant regulatory role in central metabolism and the carbon overflow pathway, metabolism-associated genes exhibited CodY-independent expression patterns under glucose starvation. Genes that were differentially expressed in response to CO2 availability showed CodY-dependent regulation, though their maximal expression did require a supply of CO2/bicarbonate. We speculate that CodY regulates the expression of environmental-responsive genes in a hierarchical manner and is likely associated with other transcription regulators that are specific for a particular environmental change.

  2. 78 FR 66763 - Notice of December 2, 2013, Meeting for Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-06

    ... National Park Service Notice of December 2, 2013, Meeting for Cape Cod National Seashore Advisory... the date of the 291st Meeting of the Cape Cod National Seashore Advisory Commission. DATES: The public meeting of the Cape Cod National Seashore Advisory Commission will be held on Monday, December 2, 2013,...

  3. 77 FR 59970 - Notice of November 14, 2012, Meeting for Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... National Park Service Notice of November 14, 2012, Meeting for Cape Cod National Seashore Advisory... the date of the Two Hundred Eighty- Sixth Meeting of the Cape Cod National Seashore Advisory Commission. DATES: The public meeting of the Cape Cod National Seashore Advisory Commission will be held...

  4. 78 FR 23783 - Notice of May 13, 2013, Meeting for Cape Cod National Seashore Advisory Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-22

    ... National Park Service Notice of May 13, 2013, Meeting for Cape Cod National Seashore Advisory Commission... of the Two Hundred Eighty- Ninth Meeting of the Cape Cod National Seashore Advisory Commission. DATES: The public meeting of the Cape Cod National Seashore Advisory Commission will be held on Monday,...

  5. Drivers of spring and summer variability in the coastal ocean offshore of Cape Cod, MA

    NASA Astrophysics Data System (ADS)

    Kirincich, Anthony R.; Gawarkiewicz, Glen G.

    2016-03-01

    The drivers of spring and summer variability within the coastal ocean east of Cape Cod, Massachusetts, a critical link between the Gulf of Maine and Mid-Atlantic Bight, are investigated using 2 years of shipboard and moored hydrographic and velocity observations from 2010 and 2011. The observations reveal sharp differences in the spring transition and along-shelf circulation due to variable freshwater and meteorological forcing, along with along-shelf pressure gradients. The role of the along-shelf pressure gradient is inferred using in situ observations of turbulent momentum flux, or Reynolds stresses, estimated from the ADCP-based velocities using recently developed methods and an inversion of the along-shelf momentum balance. During spring, the locally relevant along-shelf pressure gradient contains a sizable component that is not coupled to the along-shelf winds and often opposes the regional sea level gradient. Together with the winds, local pressure gradients dominate along-shelf transport variability during spring, while density-driven geostrophic flows appear to match the contribution of the local winds during summer. These results suggest that local effects along the Outer Cape have the potential to cause significant changes in exchange between the basins.

  6. A sampler for capturing larval and juvenile Atlantic menhaden

    USGS Publications Warehouse

    Hedrick, J.D.; Hedrick, L.R.; Margraf, F.J.

    2005-01-01

    Interest in capturing larval and juvenile Atlantic menhaden Brevoortia tyrannus for use in laboratory studies required the design and construction of a sampling device that would allow us to make collections of live fish from open-water areas. Our device for capturing 1-2.5-in larval-juvenile fish was constructed of a stainless steel frame that supported a 9.84-ft-long (3-m-long)5 cone plankton net with a 3.28-ft-diameter (1-m-diameter) opening and a 0.04-in (1-mm) mesh size. Although the plankton net was similar to that used during typical larval fish collections, the cod end was constructed of Plexiglas and was nearly watertight; this prevented impingement and injury to larval fish and provided a calm-water environment. The cod end was designed for quick release from the plankton net, and the entire cod end could be submerged into a 75-gal onboard holding tank. This design and technique obviated the netting or emerging of fish from the water until they were returned to the laboratory. ?? Copyright by the American Fisheries Society 2005.

  7. Physicochemical characterization of Atlantic Canadian seafood processing plant effluent.

    PubMed

    Jamieson, Bryan Lee; Gagnon, Graham A; Gonçalves, Alex Augusto

    2017-03-15

    The purpose of this study was to conduct a preliminary assessment of the potential impacts of Atlantic Canadian seafood processing effluents on the aquatic environment through physical-chemical characterization. Shellfish and finfish effluent samples were collected and characterized by biochemical oxygen demand (BOD5), chemical oxygen demand (COD), turbidity, total suspended solids (TSS), ammonia nitrogen (NH3-N), adsorbable organic halides (AOX), soluble BOD5 and soluble COD. Effluent concentration ranges were BOD5 (179 to 276mgL(-1)), COD (458 to 1717mgL(-1)), turbidity (28.8 to 88.3NTU), TSS (27.2 to 120.1mgL(-1)), NH3-N (1.5 to 12.9mgL(-1)) and AOX (3.2 and 0.4mgL(-1)) for flatfish and salmon processing effluents respectively, and cleanup shift AOX (3.5 and 0.5mgL(-1)). The characteristics of these effluents assessed have the potential to contaminate and degrade receiving water body environments. Improved performance may be possible with further treatment technology optimization on an effluent-specific basis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Ecological forecasting under climate change: the case of Baltic cod.

    PubMed

    Lindegren, Martin; Möllmann, Christian; Nielsen, Anders; Brander, Keith; MacKenzie, Brian R; Stenseth, Nils Chr

    2010-07-22

    Good decision making for fisheries and marine ecosystems requires a capacity to anticipate the consequences of management under different scenarios of climate change. The necessary ecological forecasting calls for ecosystem-based models capable of integrating multiple drivers across trophic levels and properly including uncertainty. The methodology presented here assesses the combined impacts of climate and fishing on marine food-web dynamics and provides estimates of the confidence envelope of the forecasts. It is applied to cod (Gadus morhua) in the Baltic Sea, which is vulnerable to climate-related decline in salinity owing to both direct and indirect effects (i.e. through species interactions) on early-life survival. A stochastic food web-model driven by regional climate scenarios is used to produce quantitative forecasts of cod dynamics in the twenty-first century. The forecasts show how exploitation would have to be adjusted in order to achieve sustainable management under different climate scenarios.

  9. Ozonation of tannery effluent for removal of cod and color.

    PubMed

    Preethi, V; Kalyani, K S Parama; Iyappan, K; Srinivasakannan, C; Balasubramaniam, N; Vedaraman, N

    2009-07-15

    Ozonation of leather dye effluent for removal of color and COD reduction covering wide range in operating parameters forms the scope of the present work. The influence of parameters such as influent pH, ozone flow rate and initial effluent concentration on ozonation efficiency has been critically examined. It has been observed from the present investigation that a maximum of COD removal efficiency of 92% has been achieved under optimum operating conditions. Further the biodegradability index of the tannery effluent has increased from an initial value of 0.18 to 0.49 during ozonation indicating favorable adaptation of ozonation as a primer to the biochemical technique to enhance the efficiency of biochemical treatment.

  10. COD and Color Removal from Real Dyeing Wastewater by Ozonation.

    PubMed

    Yang, De-min; Yuan, Jian-mei

    2016-05-01

    Ozonation of real dye wastewater for removal of color and COD reduction covering a wide range in operating parameters forms the scope of the present work. The influence of parameters such as influent pH, ozone flow rate and initial effluent concentration on ozonation efficiency has been critically examined. It has been observed from the present investigation that a maximum of COD removal efficiency of 92.5% has been achieved under optimum operating conditions (pH=11; ozone flow rate: 6×10(-3) m(3)/minute). Further the biodegradability index of the dye effluent has increased from an initial value of 0.18 to 0.49 during ozonation indicating favorable adaptation of ozonation as a primer to the biochemical technique to enhance the efficiency of biochemical treatment.

  11. A rapid liquid chromatography determination of free formaldehyde in cod.

    PubMed

    Storey, Joseph M; Andersen, Wendy C; Heise, Andrea; Turnipseed, Sherri B; Lohne, Jack; Thomas, Terri; Madson, Mark

    2015-01-01

    A rapid method for the determination of free formaldehyde in cod is described. It uses a simple water extraction of formaldehyde which is then derivatised with 2,4-dinitrophenylhydrazine (DNPH) to form a sensitive and specific chromophore for high-performance liquid chromatography (HPLC) detection. Although this formaldehyde derivative has been widely used in past tissue analysis, this paper describes an improved derivatisation procedure. The formation of the DNPH formaldehyde derivative has been shortened to 2 min and a stabilising buffer has been added to the derivative to increase its stability. The average recovery of free formaldehyde in spiked cod was 63% with an RSD of 15% over the range of 25-200 mg kg(-1) (n = 48). The HPLC procedure described here was also compared to a commercial qualitative procedure - a swab test for the determination of free formaldehyde in fish. Several positive samples were compared by both methods.

  12. 3. VIEW LOOKING NORTH WEST OVER CENTRAL ATLANTIC WITH ATLANTIC ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW LOOKING NORTH WEST OVER CENTRAL ATLANTIC WITH ATLANTIC OCEAN IN THE FOREGROUND. DENNIS HOTEL, BLENHEIM HOTEL, AND MARLBOROUGH HOTEL (LEFT TO RIGHT) ARE LOCATED IN THE CENTER OF THE PHOTOGRAPH. THE CLARIDGE HOTEL IS THE HIGHRISE IMMEDIATELY TO THE RIGHT OF THE MARLBOROUGH HOTEL - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  13. Preliminary Results of Recent Deep Drilling on Cape Cod, Massachusetts.

    PubMed

    Koteff, C; Cotton, J E

    1962-07-06

    In 1961 a 1000-foot drill hole near Harwich on Cape Cod, Massachusetts, penetrated 435 feet of Pleistocene deposits above 50 to 60 feet of crystalline limestone and phyllitic schist, and more than 500 feet of phyllitic schist with abundant quartz veins. Similar rock is known in the Pennsylvanian and Precambrian (?) sections of Massachusetts and Rhode Island. Material of Eocene age was found in earlier drilling near Provincetown, but none was identified from this hole.

  14. The CodY regulator is essential for virulence in Streptococcus suis serotype 2

    PubMed Central

    Feng, Liping; Zhu, Jiawen; Chang, Haitao; Gao, Xiaoping; Gao, Cheng; Wei, Xiaofeng; Yuan, Fangyan; Bei, Weicheng

    2016-01-01

    The main role of CodY, a global regulatory protein in most low G + C gram-positive bacteria, is in transcriptional repression. To study the functions of CodY in Streptococcus suis serotype 2 (S. suis 2), a mutant codY clone named ∆codY was constructed to explore the phenotypic variation between ∆codY and the wild-type strain. The result showed that the codY mutation significantly inhibited cell growth, adherence and invasion ability of S. suis 2 to HEp-2 cells. The codY mutation led to decreased binding of the pathogen to the host cells, easier clearance by RAW264.7 macrophages and decreased growth ability in fresh blood of Cavia porcellus. The codY mutation also attenuated the virulence of S. suis 2 in BALB/c mice. Morphological analysis revealed that the codY mutation decreased the thickness of the capsule of S. suis 2 and changed the surface structures analylized by SDS-PAGE. Finally, the codY mutation altered the expressions of many virulence related genes, including sialic acid synthesis genes, leading to a decreased sialic acid content in capsule. Overall, mutation of codY modulated bacterial virulence by affecting the growth and colonization of S. suis 2, and at least via regulating sialic acid synthesis and capsule thickness. PMID:26883762

  15. Improvement of COD removal by controlling the substrate degradability during the anaerobic digestion of recalcitrant wastewater.

    PubMed

    Kawai, Minako; Nagao, Norio; Kawasaki, Nobuyuki; Imai, Akio; Toda, Tatsuki

    2016-10-01

    The recalcitrant landfill leachate was anaerobically digested at various mixing ratios with labile synthetic wastewater to evaluate the degradation properties of recalcitrant wastewater. The proportion of leachate to the digestion system was increased in three equal steps, starting from 0% to 100%, and later decreased back to 0% with the same steps. The chemical oxygen demand (COD) for organic carbon and other components were calculated by analyzing the COD and dissolved organic carbon (DOC), and the removal efficiencies of COD carbon and COD others were evaluated separately. The degradation properties of COD carbon and COD others shifted owing to changing of substrate degradability, and the removal efficiencies of COD carbon and COD others were improved after supplying 100% recalcitrant wastewater. The UV absorptive property and total organic carbon (TOC) of each molecular size using high performance liquid chromatography (HPLC)-size exclusion chromatography (SEC) with UVA and TOC detectors were also investigated, and the degradability of different molecular sizes was determined. Although the SEC system detected extracellular polymeric substances (EPS), which are produced by microbes in stressful environments, during early stages of the experiment, EPS were not detected after feeding 100% recalcitrant wastewater. These results suggest that the microbes had acclimatized to the recalcitrant wastewater degradation. The high removal rates of both COD carbon and COD others were sustained when the proportion of labile wastewater in the substrate was 33%, indicating that the effective removal of recalcitrant COD might be controlled by changing the substrate's degradability.

  16. COD::CIF::Parser: an error-correcting CIF parser for the Perl language

    PubMed Central

    Merkys, Andrius; Vaitkus, Antanas; Butkus, Justas; Okulič-Kazarinas, Mykolas; Kairys, Visvaldas; Gražulis, Saulius

    2016-01-01

    A syntax-correcting CIF parser, COD::CIF::Parser, is presented that can parse CIF 1.1 files and accurately report the position and the nature of the discovered syntactic problems. In addition, the parser is able to automatically fix the most common and the most obvious syntactic deficiencies of the input files. Bindings for Perl, C and Python programming environments are available. Based on COD::CIF::Parser, the cod-tools package for manipulating the CIFs in the Crystallography Open Database (COD) has been developed. The cod-tools package has been successfully used for continuous updates of the data in the automated COD data deposition pipeline, and to check the validity of COD data against the IUCr data validation guidelines. The performance, capabilities and applications of different parsers are compared. PMID:26937241

  17. Positive regulation of botulinum neurotoxin gene expression by CodY in Clostridium botulinum ATCC 3502.

    PubMed

    Zhang, Zhen; Dahlsten, Elias; Korkeala, Hannu; Lindström, Miia

    2014-12-01

    Botulinum neurotoxin, produced mainly by the spore-forming bacterium Clostridium botulinum, is the most poisonous biological substance known. Here, we show that CodY, a global regulator conserved in low-G+C Gram-positive bacteria, positively regulates the botulinum neurotoxin gene expression. Inactivation of codY resulted in decreased expression of botA, encoding the neurotoxin, as well as in reduced neurotoxin synthesis. Complementation of the codY mutation in trans rescued neurotoxin synthesis, and overexpression of codY in trans caused elevated neurotoxin production. Recombinant CodY was found to bind to a 30-bp region containing the botA transcription start site, suggesting regulation of the neurotoxin gene transcription through direct interaction. GTP enhanced the binding affinity of CodY to the botA promoter, suggesting that CodY-dependent neurotoxin regulation is associated with nutritional status.

  18. COD::CIF::Parser: an error-correcting CIF parser for the Perl language.

    PubMed

    Merkys, Andrius; Vaitkus, Antanas; Butkus, Justas; Okulič-Kazarinas, Mykolas; Kairys, Visvaldas; Gražulis, Saulius

    2016-02-01

    A syntax-correcting CIF parser, COD::CIF::Parser, is presented that can parse CIF 1.1 files and accurately report the position and the nature of the discovered syntactic problems. In addition, the parser is able to automatically fix the most common and the most obvious syntactic deficiencies of the input files. Bindings for Perl, C and Python programming environments are available. Based on COD::CIF::Parser, the cod-tools package for manipulating the CIFs in the Crystallography Open Database (COD) has been developed. The cod-tools package has been successfully used for continuous updates of the data in the automated COD data deposition pipeline, and to check the validity of COD data against the IUCr data validation guidelines. The performance, capabilities and applications of different parsers are compared.

  19. Positive Regulation of Botulinum Neurotoxin Gene Expression by CodY in Clostridium botulinum ATCC 3502

    PubMed Central

    Zhang, Zhen; Dahlsten, Elias; Korkeala, Hannu

    2014-01-01

    Botulinum neurotoxin, produced mainly by the spore-forming bacterium Clostridium botulinum, is the most poisonous biological substance known. Here, we show that CodY, a global regulator conserved in low-G+C Gram-positive bacteria, positively regulates the botulinum neurotoxin gene expression. Inactivation of codY resulted in decreased expression of botA, encoding the neurotoxin, as well as in reduced neurotoxin synthesis. Complementation of the codY mutation in trans rescued neurotoxin synthesis, and overexpression of codY in trans caused elevated neurotoxin production. Recombinant CodY was found to bind to a 30-bp region containing the botA transcription start site, suggesting regulation of the neurotoxin gene transcription through direct interaction. GTP enhanced the binding affinity of CodY to the botA promoter, suggesting that CodY-dependent neurotoxin regulation is associated with nutritional status. PMID:25281376

  20. Can Georges Bank larval cod survive on a calanoid diet?

    NASA Astrophysics Data System (ADS)

    Lynch, Daniel R.; Lewis, Craig V. W.; Werner, Francisco E.

    A simple conceptual model is developed for larval fish feeding on stage-structured prey populations, in an Eulerian framework. The model combines simplified contemporary models of larval fish trophodynamics, zooplankton population dynamics, and hydrodynamic turbulence. The Eulerian view allows instructive maps of larval feeding and growth rates for individual prey species, alone or in combination. Decadally averaged MARMAP surveys of Calanus finmarchicus and Pseudocalanus spp. are analyzed for the March-April period. Quasi-static population dynamics are used to infer the abundance of the smallest stages from adult female abundance. Computed growth rates show that Calanus alone is insufficient to support the smallest cod larvae (4 and 6 mm), but provides good growth (⩾10%/day) for large larvae (10, 12 mm). Pseudocalanus alone provides generally good growth for all larvae but is mismatched spatially with observed cod spawning and subsequent larval advection. Both species together provide good growth, matched spatially with larval cod, for 6 mm and larger larvae. A dietary supplement beyond these two species is needed for the smallest larvae. The procedure provides a general method for mapping observations of zooplankton abundance, distribution and reproductive status, and their relevance to larval fish survival, when the smallest stages are not observable.

  1. Causes of COD increases in Gwangyang Bay, South Korea.

    PubMed

    Lee, Young Sik; Kang, Chang-Keun

    2010-08-05

    Water quality, the carbon isotope ratio of particulate organic matter (POM) and sediment, and the nutrients limiting phytoplankton growth were investigated to determine the cause of organic matter increase and to determine an effective countermeasure for chemical oxygen demand (COD) increase in Gwangyang Bay, South Korea. The sources of most NO(3)-N and SiO(2)-Si entering Gwangyang Bay seem to be land-based, and the primary source of P appears to be industrial complex and/or domestic wastewater. The major cause of the COD increase in Gwangyang Bay was phytoplankton growth. Phytoplankton growth was limited by N at high salinity and by P at relatively low salinity. Phytoplankton growth was more limited by N in Gwangyang Bay than in similar bays because of a strong point source of P in Gwangyang Bay. In the rainy season, phytoplankton were able to massively grow in Gwangyang Bay after heavy rainfall events because of the high input of N from runoff, input of P and Si, and increasing sunlight after the rainy season. The peak chlorophyll a concentration observed in winter may have resulted from mixing N from the lower layer and because Eucampia grew well at low water temperatures. To improve COD levels in Gwangyang Bay, it is important to control the phytoplankton growth in the rainy season, particularly by limiting the input of NO(3)-N from outside the bay.

  2. Detection of Fish Bones in Cod Fillets by UV Illumination.

    PubMed

    Wang, Sheng; Nian, Rui; Cao, Limin; Sui, Jianxin; Lin, Hong

    2015-07-01

    The presence of fish bones is now regarded as an important hazard in fishery products, and there is increasing demand for new analytical techniques to control it more effectively. Here, the fluorescent properties of cod bones under UV illumination were investigated, and the maximal wavelengths for excitation and emission were determined to be 320 nm and 515 nm, respectively, demonstrating significantly different fluorescence characteristics and much higher fluorescence intensity compared to those of fillet muscles. Based on the results, UV fluorescence-assisted candling for the detection of bones in fishery products was developed for the first time. Using cod fillets as samples, the detection ratio of this technique was calculated as 90.86%, significantly higher than that of traditional candling under daylight (76.78%). Moreover, the working efficiency of the new technique was about 26% higher than that of the traditional method. A UV fluorescence imaging framework was also developed, and a method for automatic identification of the fish bones in the cod fillets based on the linear discriminant analysis proposed by Fisher was preliminarily realized, but the detection ratio was demonstrated to be relatively poor compared to those of candling techniques. These results allow us to suggest UV-based methods as new and promising approaches for routine monitoring of bones in fishery products.

  3. COD removal characteristics in air-cathode microbial fuel cells.

    PubMed

    Zhang, Xiaoyuan; He, Weihua; Ren, Lijiao; Stager, Jennifer; Evans, Patrick J; Logan, Bruce E

    2015-01-01

    Exoelectrogenic microorganisms in microbial fuel cells (MFCs) compete with other microorganisms for substrate. In order to understand how this affects removal rates, current generation, and coulombic efficiencies (CEs), substrate removal rates were compared in MFCs fed a single, readily biodegradable compound (acetate) or domestic wastewater (WW). Removal rates based on initial test conditions fit first-order kinetics, but rate constants varied with circuit resistance. With filtered WW (100Ω), the rate constant was 0.18h(-)(1), which was higher than acetate or filtered WW with an open circuit (0.10h(-)(1)), but CEs were much lower (15-24%) than acetate. With raw WW (100Ω), COD removal proceeded in two stages: a fast removal stage with high current production, followed by a slower removal with little current. While using MFCs increased COD removal rate due to current generation, secondary processes will be needed to reduce COD to levels suitable for discharge. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. The saltatory search behavior of larval cod ( Gadus morhua)

    NASA Astrophysics Data System (ADS)

    Ruzicka, James J.; Gallager, Scott M.

    2006-11-01

    Accurate descriptions of larval fish foraging behavior are necessary for modeling energy gain through prey encounter rates. Larval cod use a saltatory foraging strategy; they swim in discrete bursts and search for prey during the periods between bursts when speed is minimal. The goals of this research were: first, to observe the behavior of larval cod in large volumes to reduce confinement effects; second, to observe behavior throughout early development; and third, to observe if larval cod adjust their foraging effort in response to foraging conditions, in this case prey density. An observation system employing stereo-paired video cameras was developed that allowed recording of the behavior of individual larvae throughout a large volume in three dimensions. The observed behavior shows that the burst phase of the foraging cycle remains constant regardless of the presence or absence of prey while the duration of each search event becomes significantly longer when prey are absent, perhaps reflecting either a greater time investment to process each search volume more thoroughly or a response to hunger. Comparison of the behavior of larvae fasted 12 h to those fasted 36 h shows that hunger state has little effect on the burst phase of the foraging cycle, but hunger does have a significant effect on overall activity level and foraging capacity.

  5. Removal of ecotoxicity and COD from tank truck cleaning wastewater.

    PubMed

    Dries, Jan; De Schepper, Wim; Geuens, Luc; Blust, Ronny

    2013-01-01

    Tank truck cleaning (TTC) activities generate highly complex wastewater. In a previous study, we found that a significant ecotoxic effect was still present in biologically treated TTC wastewater. The aim of the present study was therefore to investigate the removal of acute toxicity from TTC wastewater by a sequence of technologies routinely applied for industrial wastewater. Acute toxicity was assayed with the widely applied and standardized Vibrio fischeri bioluminescence inhibition test. During a 5-month period, raw wastewater was grab-sampled from a full-scale TTC company and treated by the different unit operations on a laboratory scale. Chemical pretreatment of the wastewater by coagulation with FeCl3 removed approx. 38% of the influent chemical oxygen demand (COD) and reduced the bioluminescence inhibition by 8%. Biological treatment with activated sludge subsequently removed another 77% of the remaining COD. This treatment step also reduced the bioluminescence inhibition but the removal efficiency varied strongly from 5 to 92% for the different samples. Powdered activated carbon almost completely removed the remaining COD and inhibition in all samples. The results suggest that conventional technologies did not suffice for complete removal of toxicity from TTC wastewater, and that advanced wastewater treatment technologies such as activated carbon are required for a satisfactory detoxification.

  6. 76 FR 3045 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-19

    ... Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act Crab Vessels Harvesting Pacific Cod for... Fisheries Act (AFA) crab vessels that are subject to sideboard limits harvesting Pacific cod for processing... for non-AFA crab vessels harvesting Pacific cod for processing by the inshore component in the Central...

  7. 75 FR 8841 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act Crab Vessels Catching Pacific Cod for... Fisheries Act (AFA) crab vessels catching Pacific cod for processing by the offshore component in the... season allowance of the 2010 Pacific cod sideboard limits apportioned to non-AFA crab vessels catching...

  8. 76 FR 4551 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-26

    ... Economic Zone Off Alaska; Pacific Cod by Non-American Fisheries Act Crab Vessels Harvesting Pacific Cod for... Fisheries Act (AFA) crab vessels that are subject to sideboard limits harvesting Pacific cod for processing... for non-AFA crab vessels harvesting Pacific cod for processing by the offshore component in the...

  9. Circum-Atlantic Project

    SciTech Connect

    Teleki, P.; Edgar, T. )

    1990-06-01

    Inspired by the success and value of the maps prepared by the Circum-Pacific Council for Energy and Mineral Resources, the International Union of Geological Sciences (IUGS) initiated the Circum-Atlantic Project (CAP) in 1987. The project is co-sponsored by the Commission for the Geological Map of the World (CGMW). Objectives of CAP are to help organize, coordinate, and stimulate the compilation and interpretation of geological, geophysical, and resources data for the Atlantic Ocean basin and adjacent continental areas and to publish these data in an integrated map series. Four regional working groups, one each for the eastern North Atlantic, western North Atlantic, eastern South Atlantic, and western South Atlantic areas have been organized, and within each of these groups specialty teams are being established to compile and interpret various types of geologic data. Based on a digital compilation of these data, a series of geologic thematic maps are planned to be prepared and displayed on a single sheet, at a scale of 1:17,000,000, for the entire Atlantic basin, and on four quadrant sheets, at a scale of 1:10,000,000. The quadrants correspond to the North-, Tethyan-, Central-, and South-Atlantic areas. The thematic series will consist of bathymetric, geologic, tectonic, magnetic, gravity, and mineral and energy resource maps. In addition, several palinspastic maps are planned to be constructed to display the geologic development of the Atlantic basin at eight geologic time periods. Transects will accompany all maps. The CAP plans support pilot projects that fit the scope and objectives of this undertaking.

  10. Evaluation of a rapid physical-chemical method for the determination of extant soluble COD.

    PubMed

    Hu, Zhiqiang; Chandran, Kartik; Smets, Barth F; Grasso, Domenico

    2002-02-01

    Characterization of total chemical oxygen demand (COD) in wastewater is critical for accurate modeling of constituent biotransformation steps. We evaluated the accuracy and precision of a commonly used soluble COD determination technique (coagulation using ZnSO4 at pH 10.5) in relation to three other physical-chemical separation techniques: destabilization with a non-hydrolyzing trivalent cation (LaCl3), sequential filtration, and ultracentrifugation. Samples of deionized water and domestic wastewater were spiked with aliquots of synthetic soluble COD and recoveries using the different separation methods were compared. Although mechanisms of coagulation using LaCl3 and ZnSO4 are different, the mean COD recoveries using these methods were in close agreement. Further, sorption of soluble COD onto zinc hydroxide precipitate flocs appeared to be negligible. The two coagulation methods yielded statistically different (p = 0.05) soluble COD values when applied to nine independent wastewater samples (obtained on nine different days). but the difference was less than 10%. The COD quantified by the coagulation techniques corresponded most closely with the < 1,000 Da molecular weight fraction defined as "truly soluble COD". Centrifugation of wastewater samples amended with mercuric chloride (HgCl2) at 10 mg/L overestimated the soluble COD concentration. Our results confirm that coagulation using either ZnSO4 or LaCI3 is appropriate for the rapid determination of soluble COD fraction in wastewater matrices.

  11. Improved COD Measurements for Organic Content in Flowback Water with High Chloride Concentrations.

    PubMed

    Cardona, Isabel; Park, Ho Il; Lin, Lian-Shin

    2016-03-01

    An improved method was used to determine chemical oxygen demand (COD) as a measure of organic content in water samples containing high chloride content. A contour plot of COD percent error in the Cl(-)-Cl(-):COD domain showed that COD errors increased with Cl(-):COD. Substantial errors (>10%) could occur in low Cl(-):COD regions (<300) for samples with low (<10 g/L) and high chloride concentrations (>25 g/L). Applying the method to flowback water samples resulted in COD concentrations ranging in 130 to 1060 mg/L, which were substantially lower than the previously reported values for flowback water samples from Marcellus Shale (228 to 21 900 mg/L). It is likely that overestimations of COD in the previous studies occurred as result of chloride interferences. Pretreatment with mercuric sulfate, and use of a low-strength digestion solution, and the contour plot to correct COD measurements are feasible steps to significantly improve the accuracy of COD measurements.

  12. Tectonics of Atlantic Canada

    USGS Publications Warehouse

    Williams, H.; Dehler, S.A.; Grant, A.C.; Oakey, G.N.

    1999-01-01

    The tectonic history of Atlantic Canada is summarized according to a model of multiple ocean opening-closing cycles. The modern North Atlantic Ocean is in the opening phase of its cycle. It was preceded by an early Paleozoic lapetus Ocean whose cycle led to formation of the Appalachian Orogen. lapetus was preceded by the Neoproterozoic Uranus Ocean whose cycle led to formation of the Grenville Orogen. The phenomenon of coincident, or almost coincident orogens and modern continental margins that relate to repeated ocean opening-closing cycles is called the Accordion Effect. An understanding of the North Atlantic Ocean and its continental margins provides insights into the nature of lapetus and the evolution of the Appalachian Orogen. Likewise, an understanding of lapetus and the Appalachian Orogen raises questions about Uranus and the development of the Grenville Orogen. Modern tectonic patterns in the North Atlantic may have been determined by events that began before 1000 m.y.

  13. South Atlantic interbasin exchange

    NASA Technical Reports Server (NTRS)

    Rintoul, Stephen Rich

    1991-01-01

    The exchange of mass and heat between the South Atlantic and the neighboring ocean basins was estimated using hydrographic data and inverse methods, in order to gain information on the links between the deep-water formation processes occurring within the Atlantic and the global thermohaline circulation. Results demonstrate that the global thermohaline cell associated with the formation and export of North Atlantic deep water (NADW) is closed primarily by a 'cold water path' in which deep water leaving the Atlantic ultimately returns as intermediate water entering the basin through Drake Passage. This conclusion conflicts with the suggestion by Gordon (1986) that the global thermohaline circulation associated with the formation of NADW is closed primarily by a 'warm water path', in which the export of NADW is compensated by an inflow of warm Indian Ocean thermocline water south of Africa.

  14. South Atlantic interbasin exchange

    NASA Technical Reports Server (NTRS)

    Rintoul, Stephen Rich

    1991-01-01

    The exchange of mass and heat between the South Atlantic and the neighboring ocean basins was estimated using hydrographic data and inverse methods, in order to gain information on the links between the deep-water formation processes occurring within the Atlantic and the global thermohaline circulation. Results demonstrate that the global thermohaline cell associated with the formation and export of North Atlantic deep water (NADW) is closed primarily by a 'cold water path' in which deep water leaving the Atlantic ultimately returns as intermediate water entering the basin through Drake Passage. This conclusion conflicts with the suggestion by Gordon (1986) that the global thermohaline circulation associated with the formation of NADW is closed primarily by a 'warm water path', in which the export of NADW is compensated by an inflow of warm Indian Ocean thermocline water south of Africa.

  15. Nitrogen removal in intermittently aerated vertical flow constructed wetlands: impact of influent COD/N ratios.

    PubMed

    Fan, Jinlin; Wang, Wengang; Zhang, Bo; Guo, Yeye; Ngo, Huu Hao; Guo, Wenshan; Zhang, Jian; Wu, Haiming

    2013-09-01

    The performance response of eight vertical flow constructed wetlands (VFCWs) to different influent COD/N ratios and intermittent aeration in domestic wastewater treatment was investigated. Almost complete nitrification was obtained by intermittent aeration, which well developed alternate anaerobic and aerobic conditions for nitrification and denitrification. Sufficient carbon source supply resulted from influent COD/N ratio of 10 simultaneously obtained high removals of COD (96%), ammonia nitrogen (99%) and total nitrogen (90%) in intermittently aerated VFCWs. In all non-aerated VFCWs, poor nitrification was observed due to oxygen deficiency whilst high COD/N ratios further led to lower COD and nitrogen removal efficiency. The results suggest that intermittent aeration combined with high influent COD/N ratios could achieve high nitrogen removal in VFCWs.

  16. A new method for COD analysis with full-spectrum based on Artificial Neural Network

    NASA Astrophysics Data System (ADS)

    Feng, Wei-wei; Li, Dan; Cai, Zong-qi; Hao, Fu-guo

    2016-09-01

    A new on-line monitoring system was developed for the determination of chemical oxygen demand (COD) in water based on full-spectrum analysis. In this system, Artificial Neural Net (ANN) work was used to obtain the transmission equation between absorbance and COD value by measuring absorption spectra of water with known COD value, and then the established equation could inverse the COD values of the unknown water samples. For the COD determination of simulated complicated water samples, the instrumental reliability was well validated by a comparison made between the ANN method and the PLS method. The monitoring system of the ANN method provided advantages of simplicity, rapidity, high precision, no consumption of reagent. And it was demonstrated an ideal alternative to real-time and on-line monitoring of COD in water.

  17. Restoring nitrification and COD removal at a refinery in the Southwest

    SciTech Connect

    Dyke, P.M.; Lucas, G.F.; Christiansen, J.A.; Smith, C.R.

    1995-12-31

    During the month of April 1993, a Southwest Texas refinery experienced a loss of nitrification and Chemical Oxygen Demand (COD) removal capacity in their activated sludge system following several consecutive days of high COD loadings. This resulted in excessive effluent ammonia (NH{sup 3}) and COD levels approaching permit levels. International Biochemical Group-Microbe Masters (Microbe Masters) was brought into the plant at the end of April to assess the situation and provide recommendations to quickly restore nitrification and COD removal. The bioaugmentation program employed at this refinery achieved the following results: (1) restoration of complete nitrification in thirteen days; (2) a 17% increase in COD removal efficiency; and (3) improved plant/operator knowledge of biological system health and performance critical to maintaining optimum BOD, COD and NH{sub 3} removal.

  18. Cod Fractions - Methods of Measurement and Use in Wastewater Treatment Technology

    NASA Astrophysics Data System (ADS)

    Myszograj, Sylwia; Płuciennik-Koropczuk, Ewelina; Jakubaszek, Anita

    2017-03-01

    The paper presents the results of studies concerning the designation of COD fraction in raw wastewater. The research was conducted in four municipal mechanical-biological sewage treatment plants and one industrial sewage treatment plant. The following fractions of COD were determined: non-biodegradable (inert) soluble SI, biodegradable soluble fraction SS, particulate slowly degradable XS and particulate non-biodegradable XI. The methodology for determining the COD fraction was based on the ATV-A131 guidelines and Łomotowski-Szpindor methodology. The real concentration of fractions in raw wastewater and the percentage of each fraction in total COD are different from data reported in the literature.

  19. Influence of temperature and turbidity on water COD detection by UV absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhou, Kun-peng; Bi, Wei-hong; Zhang, Qi-hang; Fu, Xing-hu; Wu, Guo-qing

    2016-11-01

    Ultraviolet (UV) absorption spectroscopy is used to detect the concentration of water chemical oxygen demand (COD). The UV absorption spectra of COD solutions are analyzed qualitatively and quantitatively. The partial least square (PLS) algorithm is used to model COD solution and the modeling results are compared. The influence of environmental temperature and turbidity is analyzed. These results show that the influence of temperature on the predicted value can be ignored. However, the change of turbidity can affect the detection results of UV spectra, and the COD detection error can be effectively compensated by establishing the single-element regression model.

  20. Digestibility of chitin in cod, Gadus morhua, in vivo

    NASA Astrophysics Data System (ADS)

    Danulat, Eva

    1987-12-01

    Sixteen cod, Gadus morhua (L.), were individually fed a single ration of shrimps, Crangon allmanni. Four fish were killed and examined 6, 12, 24 and 48 h after the fish had been fed. Chitinase activities were measured in the extracts of stomach contents, stomach tissue, pyloric caecae, intestinal contents and intestinal tissue. The level of enzyme activity in different parts of the digestive tract was shown to be dependent on the phase of the digestive process. High concentrations of the chitin degradation product N-acetyl-D-glucosamine were determined in the stomach and in the intestinal contents. Based on the chitin concentration in the food organisms and the individual food uptake, the amount of chitin consumed by each fish could be calculated. Only up to 9% of the ingested chitin was recovered from the intestinal contents of the fish at any given time after feeding (6, 12, 24 and 48 h). In addition, only 2.4% of the chitin consumed with the food could be recovered in the collected faeces of the fish. The 4 cod killed 48 h after feeding had completely emptied their stomach. Chitin digestion in these fish was calculated to have been 90%.

  1. Rising seas and sinking coastal marshes: Implications to Atlantic waterbirds

    USGS Publications Warehouse

    Erwin, R.M.; Prosser, D.J.; Sanders, G.

    2000-01-01

    Along the mid-Atlantic U.S. coast, relative sea level rise (RSLR) is higher than the global average of 1.5-2.0 mm/yr, ranging from about 2.5 in parts of Virginia and Delaware to about 4.0 in New Jersey (Atlantic City and Sandy Hook) and near the mouth of Chesapeake Bay, Virginia. Very few data exist on marsh elevation changes, but information from some areas in Virginia, New Jersey and New York suggest that marsh islands are not 'keeping pace' with this RSLR. We began a study in 1999 that addresses changes in sea level and marsh elevation at sites from Cape Cod to s. Virginia known to be important areas for migratory waterbirds, including waterfowl, shorebirds, wading birds, and seabirds. Marsh monitoring sites have been established and data on microhabitat use by birds during all 4 seasons is being collected at these sites. Species expected to be most vulnerable to RSLR in these marshes are breeding species such as Laughing Gulls, Common, Gull-billed and Forster's terns, Clapper Rails, and American Black Ducks. Most of these species are of special concern at state, regional, or national levels. We show how important this region to these species from a flyway perspective, with> 70% of all Atlantic coast Laughing Gulls and Forster's Terns nesting from New Jersey to Virginia.

  2. Intense habitat-specific fisheries-induced selection at the molecular Pan I locus predicts imminent collapse of a major cod fishery.

    PubMed

    Arnason, Einar; Hernandez, Ubaldo Benitez; Kristinsson, Kristján

    2009-05-27

    Predation is a powerful agent in the ecology and evolution of predator and prey. Prey may select multiple habitats whereby different genotypes prefer different habitats. If the predator is also habitat-specific the prey may evolve different habitat occupancy. Drastic changes can occur in the relation of the predator to the evolved prey. Fisheries exert powerful predation and can be a potent evolutionary force. Fisheries-induced selection can lead to phenotypic changes that influence the collapse and recovery of the fishery. However, heritability of the phenotypic traits involved and selection intensities are low suggesting that fisheries-induced evolution occurs at moderate rates at decadal time scales. The Pantophysin I (Pan I) locus in Atlantic cod (Gadus morhua), representing an ancient balanced polymorphism predating the split of cod and its sister species, is under an unusual mix of balancing and directional selection including current selective sweeps. Here we show that Pan I alleles are highly correlated with depth with a gradient of 0.44% allele frequency change per meter. AA fish are shallow-water and BB deep-water adapted in accordance with behavioral studies using data storage tags showing habitat selection by Pan I genotype. AB fish are somewhat intermediate although closer to AA. Furthermore, using a sampling design covering space and time we detect intense habitat-specific fisheries-induced selection against the shallow-water adapted fish with an average 8% allele frequency change per year within year class. Genotypic fitness estimates (0.08, 0.27, 1.00 of AA, AB, and BB respectively) predict rapid disappearance of shallow-water adapted fish. Ecological and evolutionary time scales, therefore, are congruent. We hypothesize a potential collapse of the fishery. We find that probabilistic maturation reaction norms for Atlantic cod at Iceland show declining length and age at maturing comparable to changes that preceded the collapse of northern cod at

  3. North Atlantic Circulation

    NASA Astrophysics Data System (ADS)

    Molinari, R.; Bryan, K.; Schott, F.

    The intensity of the North Atlantic winddriven and thermohaline circulation and the close proximity of many oceanographic installations make the North Atlantic a particularly favored region of the world ocean from the standpoint of research in ocean circulation. Recent increases in available data and advances in numerical modeling techniques served as the impetus to convene a joint workshop of modelers and observers working on the North Atlantic with the Scientific Committee on Oceanic Research (SCOR) Working Group (WG) 68 (“North Atlantic Circulation”). Goals of the workshop were to provide an update on data sets and models and to discuss the poleward heat flux problem and possible monitoring strategies. The joint Workshop/SCOR WG-68 meeting was convened by F. Schott (chairman of the working group; Rosenstiel School of Marine and Atmospheric Science, Miami, Fla.), K. Bryan (National Oceanic and Atmospheric Administration/ Geophysical Fluid Dynamics Laboratory (NOAA/GFDL)), and R. Molinari (NOAA/Atlantic Oceanographic and Meteorological Laboratory (NOAA/AOML)).

  4. Global Regulation by (p)ppGpp and CodY in Streptococcus mutans▿ †

    PubMed Central

    Lemos, José A.; Nascimento, Marcelle M.; Lin, Vanessa K.; Abranches, Jacqueline; Burne, Robert A.

    2008-01-01

    The RelA, RelP, and RelQ enzymes are responsible for the production of the alarmone (p)ppGpp in Streptococcus mutans. A strain lacking all three synthetases (ΔrelAPQ) does not grow in minimal medium lacking the branched-chain amino acids (BCAA) leucine or valine but grows well if isoleucine is also omitted. Here, we investigated whether there was a correlation between growth in the absence of leucine and valine with (p)ppGpp pools and the activation of CodY. By using a combination of single, double, and triple mutants lacking the (p)ppGpp synthetase enzymes, we demonstrated that the ability to grow in the absence of leucine or valine required basal levels of (p)ppGpp production by RelP and RelQ. The introduction of a codY mutation into the ΔrelAPQ strain fully restored growth in medium lacking leucine or valine, revealing that the growth-defective phenotype of ΔrelAPQ was directly linked to CodY. Lowering GTP levels through the addition of decoyinine did not alleviate CodY repression or affect the expression of genes involved in BCAA biosynthesis, suggesting that S. mutans CodY is not activated by GTP. The results of phenotypic studies revealed that the codY mutant had a reduced capacity to form biofilms and that its growth was more sensitive to low pH, showing a role for CodY in two key virulence properties of S. mutans. Microarray results revealed the extent of the CodY regulon. Notably, the identification of putative CodY-binding boxes upstream of genes that were downregulated in the codY mutant indicates that CodY may also function as a transcriptional activator in S. mutans. PMID:18539745

  5. Invasion of the Red Seaweed Heterosiphonia japonica Spans Biogeographic Provinces in the Western North Atlantic Ocean

    PubMed Central

    Newton, Christine; Bracken, Matthew E. S.; McConville, Megan; Rodrigue, Katherine; Thornber, Carol S.

    2013-01-01

    The recent invasion of the red alga Heterosiphonia japonica in the western North Atlantic Ocean has provided a unique opportunity to study invasion dynamics across a biogeographical barrier. Native to the western North Pacific Ocean, initial collections in 2007 and 2009 restricted the western North Atlantic range of this invader to Rhode Island, USA. However, through subtidal community surveys, we document the presence of Heterosiphonia in coastal waters from Maine to New York, USA, a distance of more than 700 km. This geographical distribution spans a well-known biogeographical barrier at Cape Cod, Massachusetts. Despite significant differences in subtidal community structure north and south of Cape Cod, Heterosiphonia was found at all but two sites surveyed in both biogeographic provinces, suggesting that this invader is capable of rapid expansion over broad geographic ranges. Across all sites surveyed, Heterosiphonia comprised 14% of the subtidal benthic community. However, average abundances of nearly 80% were found at some locations. As a drifting macrophyte, Heterosiphonia was found as intertidal wrack in abundances of up to 65% of the biomass washed up along beaches surveyed. Our surveys suggest that the high abundance of Heterosiphonia has already led to marked changes in subtidal community structure; we found significantly lower species richness in recipient communities with higher Heterosiphona abundances. Based on temperature and salinity tolerances of the European populations, we believe Heterosiphonia has the potential to invade and alter subtidal communities from Florida to Newfoundland in the western North Atlantic. PMID:23638018

  6. Invasion of the red seaweed Heterosiphonia japonica spans biogeographic provinces in the Western North Atlantic Ocean.

    PubMed

    Newton, Christine; Bracken, Matthew E S; McConville, Megan; Rodrigue, Katherine; Thornber, Carol S

    2013-01-01

    The recent invasion of the red alga Heterosiphonia japonica in the western North Atlantic Ocean has provided a unique opportunity to study invasion dynamics across a biogeographical barrier. Native to the western North Pacific Ocean, initial collections in 2007 and 2009 restricted the western North Atlantic range of this invader to Rhode Island, USA. However, through subtidal community surveys, we document the presence of Heterosiphonia in coastal waters from Maine to New York, USA, a distance of more than 700 km. This geographical distribution spans a well-known biogeographical barrier at Cape Cod, Massachusetts. Despite significant differences in subtidal community structure north and south of Cape Cod, Heterosiphonia was found at all but two sites surveyed in both biogeographic provinces, suggesting that this invader is capable of rapid expansion over broad geographic ranges. Across all sites surveyed, Heterosiphonia comprised 14% of the subtidal benthic community. However, average abundances of nearly 80% were found at some locations. As a drifting macrophyte, Heterosiphonia was found as intertidal wrack in abundances of up to 65% of the biomass washed up along beaches surveyed. Our surveys suggest that the high abundance of Heterosiphonia has already led to marked changes in subtidal community structure; we found significantly lower species richness in recipient communities with higher Heterosiphona abundances. Based on temperature and salinity tolerances of the European populations, we believe Heterosiphonia has the potential to invade and alter subtidal communities from Florida to Newfoundland in the western North Atlantic.

  7. [Effect of economic structure adjustment on pollution emission: a case study of COD].

    PubMed

    Li, Ming-Sheng; Zhou, Lei; Chen, Yuan-Hang; Li, Qian; Zhang, Jian-Hui

    2014-08-01

    Economic structure adjustment is an important means to reduce the emissions of pollutants. For quantitative analysis of the effect of economic structure adjustment on the reduction of pollution emission, the country was divided into four sub-regions, eastern, northeastern, central and western, and the industry was divided into 39 sectors. Taking chemical oxygen demand (COD) as an example, the influences of regional structure and industry structure adjustment on total emission reduction and emission intensity were analyzed through building a model. The results showed that, in 2000-2010: (1) COD emissions in China were reduced from 1 445 x 10(4) t to 1 238 x 10(4) t, with a total emission of 14 950 x 10(4) t in 11 years, among which the emissions from eastern area occupied the largest proportion, accounting for 35.6%. (2) In the industrial COD emissions, emission from paper and paper products was the largest, accounting for 35.8% of the industrial COD emissions. (3) The economic structure changes in the four areas reduced the COD emissions by 420 x 10(4) t, resulting in a decrease of 1.29% in COD emission intensity. (4) Industrial internal structure changes reduced the COD emissions by 533 x 10(4) t, leading to a decrease of 3.1% in COD emission intensity. The research results have certain reference value in guiding the Chinese economic structure adjustment and achieving the targets of energy-saving and emission reduction.

  8. Preparation, characterization, and in vitro cytotoxicity of COM and COD crystals with various sizes.

    PubMed

    Sun, Xin-Yuan; Ouyang, Jian-Ming; Liu, Ai-Jie; Ding, Yi-Ming; Gan, Qiong-Zhi

    2015-12-01

    Calcium oxalate crystals in urine often differ in size and crystal phase between healthy humans and patients with kidney stones. In this work, calcium oxalate monohydrate (COM) and dihydrate (COD) with sizes of about 50 nm, 100 nm, 1 μm, 3 μm, and 10 μm were prepared by varying reactant concentration, reaction temperature, solvent, mixing manner, and stirring speed. These crystals mainly had a smooth surface and no obvious pore structure, except COM-1 μm. In cell culture medium, the zeta potential of crystals became increasingly negative with increasing size, and the absolute value of zeta potential of COD was greater than the same-sized COM. Results of cell viability and PI staining assays showed that the order of injury degree in African green monkey renal epithelial (Vero) cells caused by different sizes of COD was COD-50 nm>COD-100 nm>COD-1 μm>COD-3 μm>COD-10 μm, and that of different sizes of COM was COM-1 μm>COM-50~COM-100 nm>COM-3 μm>COM-10 μm. COM-1 μm presented the highest cytotoxicity in Vero cells, which was associated with its rougher surface, larger specific surface area (SBET), and larger pore volume. Overall, these findings indicated that the physical properties of crystals play an important role in their cytotoxicity.

  9. Effect of COD/N ratio on removal performances in two subsurface wastewater infiltration systems.

    PubMed

    Fei Jing Pan Deli Tong Linli Huang Long Yu Yafei Sun Shiyue Qi Yaoyao Huang, Hexin

    2017-01-24

    Dissolved oxygen (DO), removal of COD, TP and nitrogen in subsurface wastewater infiltration systems (SWISs)with/without intermittent aeration under different influent COD/N ratios were investigated. Aerobic conditions were effectively developed in 50 cm depth of the matrix and anoxic or anaerobic conditions were not changed in 80 and 110 cm depth by intermittent aeration, which encouraged nitrification. Increased influent COD/N ratio led to lower COD and nitrogen removal in conventional SWISs. Sufficient carbon source in high COD/N ratio influent promoted denitrification with intermittent aeration. High removal rates of COD (95.68±0.21%), TP (92.02±0.28%), NH4+-N (99.33±0.05%) and TN (89.65±0.6%) were obtained with influent COD/N ratio of 12 in aerated SWISs. Under the COD/N ratio of 12 and 18, intermittent aeration boosted the growth and reproduction of nitrifying bacteria and denitrifying bacteria. Meanwhile, nitrate and nitrite reductase activities with intermittent aeration were higher than that without aeration in 80 and 110 cm depth.

  10. Sorption of chlorobenzenes to cape cod aquifer sediments

    USGS Publications Warehouse

    Barber, L.B.

    1994-01-01

    Sorption of tetra- and pentachlorobenzene by sediment from a glacial outwash aquifer on Cape Cod, MA, was evaluated. Particle size and mineralogical fractions (separated based on paramagnetic susceptibility) were characterized with respect to sediment organic carbon (SOC), mineralogy, surface area, metal oxide coatings, and spatial variability. SOC increases by a factor of 10 as particle size decreases from 500-1000 to ?? 25 % in the <63-??m fraction, and SOC is preferentially associated with the magnetic minerals. Sorption increases with decreasing particle size (increasing SOC, magnetic minerals, surface area, and metal oxyhydroxides), and the magnetic mineral fraction has greater sorption than the bulk or nonmagnetic fractions. Removal of SOC decreases sorption proportional to the decrease in SOC and results in a nonlinear isotherm.

  11. [Omega-3: from cod-liver oil to nutrigenomics].

    PubMed

    Caramia, G

    2008-08-01

    The leading role of cod-liver oil on rickets was a relevant factor in the knowledge of this disease. In 1922 the preventive and therapeutic value of cod-liver oil and sunlight against rickets in young infants was confirmed. The seasonal variation in the incidence of rickets, the role of skin pigmentation, of diet and the fact that breast milk was not an adequate source of vitamin D were understood. The discovery of essential fatty acids omega-6 and omega-3 have shown that deficiencies, mainly of omega-3 long chain polyunsaturated fatty acids, result in visual and cognitive impairment and disturbances in mental functions in infants and also in cognitive function in adults, as fatty acids are beneficial to vascular health and may forestall cerebrovascular disease and thus dementia. An adequate ratio of n-6 and n-3 fatty acids may promote a healthier balance of eicosanoids, which would protect membrane function with a nutraceutical function. Dietary lipids not only influence the biophysical state of the cell membranes but, via direct and indirect routes, they also act on multiple pathways including signalling, gene and protein activities, protein modifications and they probably play important role in modulating protein aggregation. Significant advances have been made in understanding the relation between dietary factors and inflammation, which is a central component of many chronic diseases, including coronary artery disease, rheumatoid arthritis, cancer prevention. However, the identification of those who will or will not benefit from dietary intervention strategies remains a major obstacle. Adequate knowledge about how the responses depend on an individual's genetic background (nutrigenetic effects), the cumulative effects of food components on genetic expression profiles through nutrigenomics mechanism, may assist in identifying responders and non-responders. Thus, fish and fish oil consumption might encourage brain development and gene expression to brain

  12. CodY Regulates Expression of the Bacillus subtilis Extracellular Proteases Vpr and Mpr

    PubMed Central

    Barbieri, Giulia; Voigt, Birgit; Albrecht, Dirk; Hecker, Michael; Albertini, Alessandra M.; Sonenshein, Abraham L.; Ferrari, Eugenio

    2015-01-01

    ABSTRACT CodY is a global transcriptional regulator in low-G+C Gram-positive bacteria that is responsive to GTP and branched-chain amino acids. By interacting with its two cofactors, it is able to sense the nutritional and energetic status of the cell and respond by regulating expression of adaptive genetic programs. In Bacillus subtilis, more than 200 genes, including those for peptide transporters, intracellular proteolytic enzymes, and amino acid degradative pathways, are controlled by CodY. In this study, we demonstrated that expression of two extracellular proteases, Vpr and Mpr, is negatively controlled by CodY. By gel mobility shift and DNase I footprinting assays, we showed that CodY binds to the regulatory regions of both genes, in the vicinity of their transcription start points. The mpr gene is also characterized by the presence of a second, higher-affinity CodY-binding site located at the beginning of its coding sequence. Using strains carrying vpr- or mpr-lacZ transcriptional fusions in which CodY-binding sites were mutated, we demonstrated that repression of both protease genes is due to the direct effect by CodY and that the mpr internal site is required for regulation. The vpr promoter is a rare example of a sigma H-dependent promoter that is regulated by CodY. In a codY null mutant, Vpr became one of the more abundant proteins of the B. subtilis exoproteome. IMPORTANCE CodY is a global transcriptional regulator of metabolism and virulence in low-G+C Gram-positive bacteria. In B. subtilis, more than 200 genes, including those for peptide transporters, intracellular proteolytic enzymes, and amino acid degradative pathways, are controlled by CodY. However, no role for B. subtilis CodY in regulating expression of extracellular proteases has been established to date. In this work, we demonstrate that by binding to the regulatory regions of the corresponding genes, B. subtilis CodY negatively controls expression of Vpr and Mpr, two extracellular

  13. Long-term effects of the transient COD concentration on the performance of microbial fuel cells.

    PubMed

    Mateo, S; Gonzalez Del Campo, A; Lobato, J; Rodrigo, M; Cañizares, P; Fernandez-Morales, F J

    2016-07-08

    In this work, the long-term effects of transient chemical oxygen demands (COD) concentrations over the performance of a microbial fuel cell were studied. From the obtained results, it was observed that the repetitive change in the COD loading rate during 12 h conditioned the behavior of the system during periods of up to 7 days. The main modifications were the enhancement of the COD consumption rate and the exerted current. These enhancements yielded increasing Coulombic efficiencies (CEs) when working with COD concentrations of 300 mg/L, but constant CEs when working with COD concentrations from 900 to 1800 mg/L. This effect could be explained by the higher affinity for the substrate of Geobacter than that of the nonelectrogenic organisms such as Clostridia. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:883-890, 2016.

  14. [Influence of substrate COD on methane production in single-chambered microbial electrolysis cell].

    PubMed

    Teng, Wen-Kai; Liu, Guang-Li; Luo, Hai-Ping; Zhang, Ren-Duo; Fu, Shi-Yu

    2015-03-01

    The chemical oxygen demand (COD) of substrate can affect the microbial activity of both anode and cathode biofilm in the single-chamber methanogenic microbial electrolysis cell (MEC). In order to investigate the effect of COD on the performance of MEC, a single chamber MEC was constructed with biocathode. With the change of initial concentration of COD (700, 1 000 and 1 350 mg x L(-1)), the methane production rate, COD removal and energy efficiency in the MEC were examined under different applied voltages. The results showed that the methane production rate and COD removal increased with the increasing COD. With the applied voltage changing from 0.3 to 0.7 V, the methane production rate increased at the COD of 700 mg x L(-1), while it increased at first and then decreased at the COD of 1000 mg x L(-1) and 1350 mg x L(-1). A similar trend was observed for the COD removal. The cathode potential reached the minimum (- 0.694 ± 0.001) V as the applied voltage was 0.5 V, which therefore facilitated the growth of methanogenic bacteria and improved the methane production rate and energy efficiency of the MEC. The maximum energy income was 0.44 kJ ± 0.09 kJ (1450 kJ x m(-3)) in the MEC, which was obtained at the initial COD of 1000 mg x L(-1) and the applied voltage of 0.5 V. Methanogenic MECs could be used for the treatment of wastewaters containing low organic concentrations to achieve positive energy production, which might provide a new method to recover energy from low-strength domestic wastewater.

  15. GEMINI-6 - RECOVERY - ATLANTIC

    NASA Image and Video Library

    1965-12-16

    S65-61824 (16 Dec. 1965) --- A helicopter hovers over the Gemini-6 spacecraft after it splashed down 12 miles from the aircraft carrier USS Wasp in the western Atlantic recovery area at 10:29 a.m. Dec. 16, 1965. Photo credit: NASA or National Aeronautics and Space Administration

  16. 78 FR 18896 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Less Than 60...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-28

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Less Than 60 feet (18.3 meters) Length Overall... directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters (m)) length overall...

  17. 76 FR 12606 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Less Than 60...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-08

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Less Than 60 Feet (18.3 m) Length Overall Using... for Pacific cod by catcher vessels less than 60 feet (18.3 m) length overall (LOA) using jig or...

  18. Structural and biophysical analysis of interactions between cod and human uracil-DNA N-glycosylase (UNG) and UNG inhibitor (Ugi)

    SciTech Connect

    Assefa, Netsanet Gizaw; Niiranen, Laila; Johnson, Kenneth A.; Leiros, Hanna-Kirsti Schrøder; Smalås, Arne Oskar; Willassen, Nils Peder; Moe, Elin

    2014-08-01

    A structural and biophysical study of the interactions between cod and human uracil-DNA N-glycosylase (UNG) and their inhibitor Ugi is presented. The stronger interaction between cod UNG and Ugi can be explained by a greater positive electrostatic surface potential. Uracil-DNA N-glycosylase from Atlantic cod (cUNG) shows cold-adapted features such as high catalytic efficiency, a low temperature optimum for activity and reduced thermal stability compared with its mesophilic homologue human UNG (hUNG). In order to understand the role of the enzyme–substrate interaction related to the cold-adapted properties, the structure of cUNG in complex with a bacteriophage encoded natural UNG inhibitor (Ugi) has been determined. The interaction has also been analyzed by isothermal titration calorimetry (ITC). The crystal structure of cUNG–Ugi was determined to a resolution of 1.9 Å with eight complexes in the asymmetric unit related through noncrystallographic symmetry. A comparison of the cUNG–Ugi complex with previously determined structures of UNG–Ugi shows that they are very similar, and confirmed the nucleotide-mimicking properties of Ugi. Biophysically, the interaction between cUNG and Ugi is very strong and shows a binding constant (K{sub b}) which is one order of magnitude larger than that for hUNG–Ugi. The binding of both cUNG and hUNG to Ugi was shown to be favoured by both enthalpic and entropic forces; however, the binding of cUNG to Ugi is mainly dominated by enthalpy, while the entropic term is dominant for hUNG. The observed differences in the binding properties may be explained by an overall greater positive electrostatic surface potential in the protein–Ugi interface of cUNG and the slightly more hydrophobic surface of hUNG.

  19. Episodic Eolian Sand Deposition in the Past 4000 Years in Cape COD National Seashore, Massachusetts, USA in Response to Possible Hurricane/storm and Anthropogenic Disturbances

    NASA Astrophysics Data System (ADS)

    Forman, Steven

    2015-02-01

    The eolian sand depositional record for a dune field within Cape Cod National Seashore, Massachusetts is posit as a sensitive indicator of environmental disturbances in the late Holocene from a combination of factors such as hurricane/storm and forest fire occurrence, and anthropogenic activity. Stratigraphic and sedimentologic observations, particularly the burial of spodosol-like soils, and associated 14C and OSL ages that are concordant indicate at least six eolian depositional events at ca. 3750, 2500, 1800, 960, 430 and <250 years ago. The two oldest events are documented at just one locality and thus, the pervasiveness of this eolian activity is unknown. However, the four younger events are identified in three or more sites and show evidence for dune migration and sand sheet accretion. The timing of eolian deposition, particularly the initiation age, corresponds to documented periods of increased storminess/hurricane activity in the North Atlantic Ocean at ca. 2.0 to 1.6, and 1.0 ka and also a wetter coastal climate, which suppressed the occurrence of forest fire. Thus, local droughts are not associated with periods of dune movement in this mesic environment. Latest eolian activity on outer Cape Cod commenced in the past 300 to 500 years and may reflect multiple factors including broad-scale landscape disturbance with European colonization, an increased incidence of forest fires and heightened storminess. Eolian systems of Cape Cod appear to be sensitive to landscape disturbance and prior to European settlement may reflect predominantly hurricane/storm disturbance, despite generally mesic conditions in past 4 ka.

  20. Atlantic tropical cyclones revisited

    NASA Astrophysics Data System (ADS)

    Mann, Michael E.; Emanuel, Kerry A.; Holland, Greg J.; Webster, Peter J.

    Vigorous discussions have taken place recently in Eos [e.g., Mann and Emanuel, 2006; Landsea, 2007] and elsewhere [Emanuel, 2005; Webster et al., 2005; Hoyos et al., 2006; Trenberth and Shea, 2006; Kossin et al., 2007] regarding trends in North Atlantic tropical cyclone (TC) activity and their potential connection with anthropogenic climate change. In one study, for example [Landsea, 2007], it is argued that a substantial underestimate of Atlantic tropical cyclone counts in earlier decades arising from insufficient observing systems invalidates the conclusion that trends in TC behavior may be connected to climate change. Here we argue that such connections are in fact robust with respect to uncertainties in earlier observations.Several recent studies have investigated trends in various measures of TC activity. Emanuel [2005] showed that a measure of total power dissipation by TCs (the power dissipation index, or PDI) is highly correlated with August-October sea surface temperatures (SST) over the main development region (MDR) for Atlantic TCs over at least the past half century. Some support for this conclusion was provided by Sriver and Ruber [2006]. Webster et al. [2005] demonstrated a statistically significant increase in recent decades in both the total number of the strongest category cyclones (categories 4 and 5) and the proportion of storms reaching hurricane intensity. Hoyos et al. [2006] showed that these increases were closely tied to warming trends in tropical Atlantic SST, while, for example, the modest decrease in vertical wind shear played a more secondary role. Kossin et al. [2007] called into question some trends in other basins, based on a reanalysis of past TC data, but they found the North Atlantic trends to be robust.

  1. South Atlantic summary report

    SciTech Connect

    Havran, K.J.; Wiese, J.D.

    1983-12-01

    To date, four Federal offshore oil-and-gas leasing actions have occurred in the South Atlantic Region. Two additional South Atlantic lease offerings remain on the July 1982 final 5-year OCS oil-and-gas leasing schedule before June 1987. The South Atlantic Region consists of three major sedimentary basins: the Carolina Trough, the Blake Plateau, and the Southeast Georgia Embayment. Lease Sale 43, the first in the South Atlantic Region, featured blocks for exploration in the Southeast Georgia Embayment. Offshore operators drilled a total of six exploratory wells on blocks leased in Lease Sale 43. All were dry. The 43 leases from Lease Sale 43 have now expired, some blocks were relinquished earlier by their lease-holders. In the recent Lease Sales 56 and RS-2, and in the South Atlantic Lease Offering (July 1983), blocks leased were largely concentrated in the Carolina Trough Basin. Exploration of these blocks may begin anew in early 1984. The blocks are in deep water and will require careful, long-range planning before drilling can commence. As of July 1983, all 66 leases from the above three sales are active. Two plans of exploration have been approved by Minerals Management Service for exploration on blocks leased in Lease Sale 56. The plans are for Russell Area, Blocks 709 and 710, and Manteo Area, Block 510. Blocks 709 and 710 are held by ARCO, and Block 510 is held by Chevron. Based on current plans of exploration, operations will begin in 1984, first by Chevron, and sometime later by ARCO. Operations will be supported by a temporary service base to be established at Morehead City, North Carolina. 6 references, 4 figures.

  2. Host size-dependent anisakid infection in Baltic cod Gadus morhua associated with differential food preferences.

    PubMed

    Zuo, Shaozhi; Huwer, Bastian; Bahlool, Qusay; Al-Jubury, Azmi; Daugbjerg Christensen, Nanna; Korbut, Rozalia; Kania, Per; Buchmann, Kurt

    2016-06-15

    A significant increase in the infection level of Baltic cod Gadus morhua with the anisakid nematode larvae Contracaecum osculatum and Pseudoterranova decipiens has been recorded during recent years due to the expanding local population of grey seals Halichoerus grypus, which act as final hosts for these parasites. Here, we report from an investigation of 368 cod (total length [TL] 6-49 cm; caught in ICES Subdivision 25) that the infection level of juvenile cod (TL 6-30 cm) with larvae of C. osculatum and P. decipiens is absent or very low, whereas it increases drastically in larger cod (TL 31-48 cm). A third nematode Hysterothylacium aduncum was rarely found. The study indicates that the prey animals for large cod act as transport hosts for the parasite larvae. Analyses of stomach contents of cod caught in the same area (2007-2014) showed that small benthic organisms (including polychaetes Harmothoë sarsi) are preferred food items by small cod, the isopod Saduria entomon is taken by all size classes, and sprat Sprattus sprattus are common prey items for cod larger than 30 cm. Parasitological investigations (microscopic and molecular analyses) of H. sarsi (100 specimens) and S. entomon (40 specimens) did not reveal infection in these invertebrates, but 11.6% of sprat (265 specimens examined) was shown to be infected with 1-8 C. osculatum third stage larvae per fish. Analyses of sprat stomach contents confirmed that copepods and cladocerans are the main food items of sprat. These observations suggest that the C. osculatum life cycle in the Baltic Sea includes grey seals as final hosts, sprat as the first transport host and cod as second transport host. It may be speculated that sprat obtain infection by feeding on copepods and/or cladocerans, which could serve as the first intermediate hosts. One cannot exclude the possibility that the size-dependent C. osculatum infection of cod may contribute (indirectly or directly) to the differential mortality of larger cod

  3. Atlantic Warm Pool acting as a link between Atlantic Multidecadal Oscillation and Atlantic tropical cyclone activity

    NASA Astrophysics Data System (ADS)

    Wang, Chunzai; Lee, Sang-Ki; Enfield, David B.

    2008-05-01

    Multidecadal variability of Atlantic tropical cyclone activity is observed to relate to the Atlantic Multidecadal Oscillation (AMO), a mode manifesting primarily in sea surface temperature (SST) in the high latitudes of the North Atlantic. In the low latitudes of the North Atlantic, a large body of warm water called the Atlantic Warm Pool (AWP) comprises the Gulf of Mexico, the Caribbean Sea, and the western tropical North Atlantic. AWP variability occurs on both interannual and multidecadal timescales as well as with a secular variation. The AWP multidecadal variability coincides with the signal of the AMO; that is, the warm (cool) phases of the AMO are characterized by repeated large (small) AWPs. Since the climate response to the North Atlantic SST anomalies is primarily forced at the low latitudes and the AWP is in the path of or a birthplace for Atlantic tropical cyclones, the influence of the AMO on Atlantic tropical cyclone activity may operate through the mechanism of the AWP-induced atmospheric changes. The AWP-induced changes related to tropical cyclones that we emphasize here include a dynamical parameter of tropospheric vertical wind shear and a thermodynamical parameter of convective instability. More specifically, an anomalously large (small) AWP reduces (enhances) the vertical wind shear in the hurricane main development region and increases (decreases) the moist static instability of the troposphere, both of which favor (disfavor) Atlantic tropical cyclone activity. This is the most plausible way in which the AMO relationship with Atlantic tropical cyclones can be understood.

  4. Late-Exponential Gene Expression in codY-Deficient Bacillus anthracis in a Host-Like Environment.

    PubMed

    Kim, Se Kye; Jung, Kyoung Hwa; Yoon, Sung Nyo; Kim, Yun Ki; Chai, Young Gyu

    2016-11-01

    CodY is a pleiotropic regulator commonly found in Gram-positive bacteria and regulates various biological processes during the stringent response in a nutrient-limiting environment. CodY also participates in virulence factor expression in many low G+C Gram-positive pathogens, as observed in Bacillus anthracis. However, the mechanism by which B. anthracis CodY regulates metabolism and virulence factors in response to environmental changes is unclear. Here, we attempted to identify the link between CodY and B. anthracis regulation with codY-deficient and codY-overexpressing mutants using high-throughput transcriptional analysis. Growth pattern analyses of codY mutants in both rich and minimal media showed defects in early cell proliferation, with opposite patterns in the early stationary phase: CodY overexpression prolonged bacterial growth, whereas deletion inhibited growth. RNA sequencing of codY-deficient B. anthracis showed both positive and negative changes in the gene expression of proteases and virulence factors as well as genes related to stringent response-related metabolism and biosynthetic processing. We also found that changes in codY expression could alter virulence gene expression of B. anthracis, suggesting modes of regulation in its virulence in a CodY concentration-dependent manner. Collectively, we conclude from these results that CodY can both positively and negatively regulate its regulon via direct and/or indirect approaches, and that its mode of regulation may be concentration dependent.

  5. 77 FR 23159 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-18

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands management... directed fishing for Pacific cod by catcher vessels using trawl gear in the BSAI. After the effective...

  6. 77 FR 9589 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-17

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Trawl Gear in the Western Regulatory Area... directed fishing for Pacific cod by catcher/processors (C/Ps) using trawl gear in the Western Regulatory... of the 2012 Pacific cod total allowable catch apportioned to C/Ps using trawl gear in the...

  7. 76 FR 20891 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-14

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... directed fishing for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands... allowable catch (TAC) of Pacific cod allocated to catcher vessels using trawl gear in the BSAI....

  8. 75 FR 16359 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands management... cod allowable catch (TAC) specified for catcher vessels using trawl gear in the BSAI. DATES:...

  9. 76 FR 22057 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... directed fishing for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands... allowable catch (TAC) of Pacific cod allocated to catcher vessels using trawl gear in the BSAI....

  10. 75 FR 12463 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands management... cod allowable catch (TAC) specified for catcher vessels using trawl gear in the BSAI. DATES:...

  11. 76 FR 18663 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-05

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands management... cod allowable catch (TAC) specified for catcher vessels using trawl gear in the BSAI. DATES:...

  12. 78 FR 23864 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook-and-line Gear in the Western... directed fishing for Pacific cod by catcher/processors (C/Ps) using hook-and-line gear in the Western... allowance of the 2013 Pacific cod total allowable catch apportioned to C/Ps using hook-and-line gear in...

  13. 77 FR 19564 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Central Regulatory Area of... for Pacific cod by catcher vessels (CVs) using trawl gear in the Central Regulatory Area of the Gulf... Pacific cod total allowable catch apportioned to CVs using trawl gear in the Central Regulatory Area...

  14. 77 FR 11776 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook-and-Line Gear in the Central... directed fishing for Pacific cod by catcher/processors (C/Ps) using hook-and-line gear in the Central... allowance of the 2012 Pacific cod total allowable catch apportioned to C/Ps using hook-and-line gear in...

  15. 78 FR 4346 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-22

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Trawl Gear in the Western Regulatory Area... directed fishing for Pacific cod by catcher/processors (C/Ps) using trawl gear in the Western Regulatory... fisheries data in a timely fashion and would delay the directed fishing closure of Pacific cod for...

  16. 75 FR 7976 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ...: NMFS is prohibiting directed fishing for Pacific cod by American Fisheries Act (AFA) trawl catcher... exceeding the A season allowance of the 2010 Pacific cod total allowable catch (TAC) specified for AFA trawl... cod TAC allocated to AFA trawl catcher-processors in the BSAI is 2,600 metric tons (mt) as...

  17. 77 FR 10668 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-23

    ...: NMFS is prohibiting directed fishing for Pacific cod by American Fisheries Act (AFA) trawl catcher... exceeding the A season allowance of the 2012 Pacific cod total allowable catch (TAC) specified for AFA trawl... cod TAC specified for AFA trawl catcher-processors in the BSAI is 4,021 metric tons as established...

  18. 76 FR 24404 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ... cod by catcher vessels less than 60 feet (18.3 meters) length overall (LOA) using hook-and-line or pot... use the 2011 total allowable catch of Pacific cod allocated to catcher vessels less than 60 feet LOA... closed directed fishing for Pacific cod by catcher vessels less than 60 feet LOA using hook-and-line or...

  19. 78 FR 53369 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ... cod by catcher vessels less than 60 feet (18.3 meters) length overall (LOA) using hook-and-line or pot... use the 2013 total allowable catch of Pacific cod allocated to catcher vessels less than 60 feet LOA... CFR part 679. NMFS closed directed fishing for Pacific cod by catcher vessels less than 60 feet LOA...

  20. 77 FR 76425 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Central...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... Off Alaska; Reallocation of Pacific Cod in the Central Regulatory Area of the Gulf of Alaska... projected unused amount of Pacific cod from catcher vessels using trawl gear to vessels using pot gear and... catch of Pacific cod to be harvested. DATES: Effective December 26, 2012, through 2400 hrs, Alaska...

  1. 75 FR 17315 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-06

    ... Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher Processors Using Trawl Gear in the...: NMFS is prohibiting directed fishing for Pacific cod by American Fisheries Act (AFA) trawl catcher... exceeding the B season allowance of the 2010 Pacific cod total allowable catch (TAC) specified for AFA...

  2. 77 FR 11412 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-27

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Western Regulatory Area of... for Pacific cod by catcher vessels (CVs) using trawl gear in the Western Regulatory Area of the Gulf... Pacific cod total allowable catch apportioned to CVs using trawl gear in the Western Regulatory Area...

  3. 77 FR 19144 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-30

    ... Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher/Processors Using Trawl Gear in the...: NMFS is prohibiting directed fishing for Pacific cod by American Fisheries Act (AFA) trawl catcher... exceeding the B season allowance of the 2012 Pacific cod total allowable catch specified for AFA...

  4. 77 FR 65640 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-30

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the Central Regulatory Area of the Gulf... directed fishing for Pacific cod by vessels using pot gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to fully use the 2012 Pacific cod total allowable catch...

  5. 78 FR 23683 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-22

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Trawl Gear in the Central Regulatory Area... directed fishing for Pacific cod by catcher/processors (C/Ps) using trawl gear in the Central Regulatory... of the 2013 Pacific cod total allowable catch apportioned to C/Ps using trawl gear in the...

  6. 75 FR 8840 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian... for Pacific cod by pot catcher/processors in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary to prevent exceeding the A season apportionment of the 2010 Pacific cod...

  7. 77 FR 8177 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the Central Regulatory Area of the Gulf... for Pacific cod by vessels using pot gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to prevent exceeding the A season allowance of the 2012 Pacific cod...

  8. 75 FR 792 - Fisheries of the Economic Exclusive Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-06

    ... Exclusive Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian Islands AGENCY: National Marine...: Temporary rule; modification of a closure. SUMMARY: NMFS is opening directed fishing for Pacific cod by catcher Pacific cod by catcher/processors using hook-and-line gear in the Bering Sea and Aleutian...

  9. 78 FR 55228 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Western...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-10

    ... Economic Zone Off Alaska; Reallocation of Pacific Cod in the Western Regulatory Area of the Gulf of Alaska... projected unused amount of Pacific cod from trawl catcher/processors to catcher vessels using hook-and- line... necessary to allow the 2013 total allowable catch of Pacific cod in the Western Regulatory Area of the...

  10. 78 FR 18528 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-27

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Central Regulatory Area of... for Pacific cod by catcher vessels (CVs) using trawl gear in the Central Regulatory Area of the Gulf... Pacific cod total allowable catch apportioned to CVs using trawl gear in the Central Regulatory Area...

  11. 78 FR 15643 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-12

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands management... Pacific cod total allowable catch allocated to trawl catcher vessels in the BSAI. DATES: Effective...

  12. 77 FR 20571 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Hook...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Hook-and-Line Gear in the Western Regulatory... directed fishing for Pacific cod by catcher vessels (CVs) using hook-and-line gear in the Western... allowance of the 2012 Pacific cod total allowable catch apportioned to CVs using hook-and-line gear in...

  13. 75 FR 7403 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-19

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook-and-Line Gear in the Bering Sea and... directed fishing for Pacific cod by catcher/processors using hook-and-line gear in the Bering Sea and... allowance of the 2010 Pacific cod total allowable catch (TAC) allocated to catcher/processors using...

  14. 77 FR 14305 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Jig Gear in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-09

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Using Jig Gear in the Central Regulatory Area of the Gulf... for Pacific cod by vessels using jig gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to prevent exceeding the A season allowance of the 2012 Pacific cod...

  15. 77 FR 19147 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-30

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian... directed fishing for Pacific cod by catcher vessels using trawl gear in the Bering Sea and Aleutian Islands... cod total allowable catch (TAC) allocated to trawl catcher vessels in the BSAI. DATES: Effective...

  16. 77 FR 6683 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-09

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the Western Regulatory Area of the Gulf... for Pacific cod by vessels using pot gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to prevent exceeding the A season allowance of the 2012 Pacific cod...

  17. 78 FR 25004 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Hook...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Hook-and-Line Gear in the Western Regulatory... directed fishing for Pacific cod by catcher vessels (CVs) using hook-and-line gear in the Western... allowance of the 2013 Pacific cod total allowable catch apportioned to CVs using hook-and-line gear in...

  18. 77 FR 39183 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Jig Gear in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Using Jig Gear in the Central Regulatory Area of the Gulf... for Pacific cod by vessels using jig gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to prevent exceeding the 2012 Pacific cod total allowable catch specified...

  19. 78 FR 11790 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-20

    ... Economic Zone Off Alaska; Pacific Cod by Catcher Vessels Using Trawl Gear in the Western Regulatory Area of... for Pacific cod by catcher vessels (CVs) using trawl gear in the Western Regulatory Area of the Gulf... Pacific cod total allowable catch apportioned to CVs using trawl gear in the Western Regulatory Area...

  20. 78 FR 7280 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ... Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the Western Regulatory Area of the Gulf... for Pacific cod by vessels using pot gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to prevent exceeding the A season allowance of the 2013 Pacific cod...

  1. 77 FR 21683 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/processors Using...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-11

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/processors Using Trawl Gear in the Central Regulatory Area... directed fishing for Pacific cod by catcher/processors (C/Ps) using trawl gear in the Central Regulatory... of the 2012 Pacific cod total allowable catch apportioned to C/Ps using trawl gear in the...

  2. 77 FR 34853 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher/Processors Using Trawl Gear in the...: NMFS is prohibiting directed fishing for Pacific cod by American Fisheries Act (AFA) trawl catcher... exceeding the 2012 Pacific cod total allowable catch specified for AFA trawl catcher/processors in the...

  3. 75 FR 71045 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod in the Western Regulatory Area...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... Economic Zone Off Alaska; Pacific Cod in the Western Regulatory Area of the Gulf of Alaska AGENCY: National...: Temporary rule; prohibition of retention. SUMMARY: NMFS is prohibiting retention of Pacific cod by vessels catching Pacific cod for processing by the inshore component in the Western Regulatory Area of the Gulf...

  4. 78 FR 7280 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ... Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian... for Pacific cod by pot catcher/processors in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary to prevent exceeding the A season apportionment of the 2013 Pacific cod...

  5. 77 FR 65837 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-31

    ... Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering Sea and Aleutian Islands Management... unused amounts of Pacific cod from catcher vessels using trawl gear to American Fisheries Act trawl... area. This action is necessary to allow the 2012 total allowable catch of Pacific cod to be...

  6. Interactive Regulation by the Bacillus subtilis Global Regulators CodY and ScoC

    PubMed Central

    BELITSKY, BORIS R.; BARBIERI, GIULIA; ALBERTINI, ALESSANDRA M.; FERRARI, EUGENIO; STRAUCH, MARK A.; SONENSHEIN, ABRAHAM L.

    2015-01-01

    SUMMARY CodY and ScoC are Bacillus subtilis transcriptional regulators that control the expression of dozens of genes and operons. Using scoC-lacZ fusions and DNA-binding experiments, we show here that scoC is directly repressed by CodY. This effect creates multiple forms of cascade regulation. For instance, expression of the dtpT gene, which is directly and negatively controlled by ScoC and encodes a putative oligopeptide permease, was activated indirectly by CodY due to CodY-mediated repression of scoC. The opp operon, which encodes an oligopeptide permease that is essential for sporulation and genetic competence development, proved to be a direct target of repression by both ScoC and CodY, but was not significantly affected in codY or scoC single mutants. The combined actions of CodY and ScoC maintain opp repression when either one of the regulators loses activity, but limit the level of repression to that provided by one of the regulators acting alone. Under conditions of nitrogen limitation, repression by ScoC of dtpT and opp was partly prevented by TnrA. Thus, the functioning of ScoC is determined by other transcription factors via modulation of its expression or DNA binding. PMID:25966844

  7. COD removal efficiency and mechanism of HMBR in high volumetric loading for ship domestic sewage treatment.

    PubMed

    Zhu, Linan; He, Hailing; Wang, Chunli

    2016-10-01

    The hybrid membrane bioreactor (HMBR) has been applied in ship domestic sewage treatment under high volumetric loading for ship space saving. The mechanism and influence factors on the efficiency, including hydraulic retention time (HRT), dissolved oxygen (DO) of chemical oxygen demand (COD) removal were investigated. The HMBR's average COD removal rate was up to 95.13% on volumetric loading of 2.4 kgCOD/(m(3)•d) and the COD concentration in the effluent was 48.5 mg/L, far below the International Maritime Organization (IMO) discharge standard of 125 mg/L. DO had a more remarkable effect on the COD removal efficiency than HRT. In addition, HMBR revealed an excellent capability of resisting organics loading impact. Within the range of volumetric loading of 0.72 to 4.8 kg COD/(m(3)•d), the effluent COD concentration satisfied the discharge requirement of IMO. It was found that the organics degradation in the aeration tank followed the first-order reaction, with obtained kinetic parameters of vmax (2.79 d(-1)) and Ks (395 mg/L). The original finding of this study had shown the effectiveness of HMBR in organic contaminant degradation at high substrate concentration, which can be used as guidance in the full scale of the design, operation and maintenance of ship domestic sewage treatment devices.

  8. Coupling of anaerobic digester and microbial fuel cell for COD removal and ammonia recovery.

    PubMed

    Kim, Taeyoung; An, Junyeong; Jang, Jae Kyung; Chang, In Seop

    2015-11-01

    Microbial fuel cells (MFCs) were investigated for use in removing total ammonia nitrogen (TAN) and residual COD from effluent digested in an anaerobic digester (AD) fed with actual swine wastewater for 32 days in batch mode. Cumulative COD removal in the AD was as high as 59,647±2096 mg/L (80.5% removed), whereas TAN removal in the AD was negligible at 296±116 mg-N/L (5.8% removed), causing a decrease in the COD/TAN ratio from 14.5 to 3.0. In a subsequent MFC system, 77.5% of TAN was removed at 36 days, leading to an increase in COD/TAN ratio from 4.6 to 8.1. As a result, the COD in the anode was further reduced from 19,319±417 mg/L to 7519±554 mg/L (61.1% removed). From these results, removing the TAN in MFCs was found to increase the COD/TAN ratio, with the COD being further degraded.

  9. Seafloor environments in Cape Cod Bay, a large coastal embayment

    USGS Publications Warehouse

    Knebel, H. J.; Rendigs, R. R.; List, J.H.; Signell, R.P.

    1996-01-01

    Cape Cod Bay is a glacial, semi-enclosed embayment that has a patchy distribution of modern seafloor sedimentary environments of erosion or nondeposition, deposition, and sediment reworking. Sidescan-sonar records and supplemental bathymetric, sedimentary, subbottom, and physical- oceanographic data indicate that the characteristics and distribution of these three categories of bottom environments are controlled by a combination of geologic and oceanographic processes that range from episodic to long-term and from regional to local. (1) Environments of erosion or nondeposition comprise exposares of bedrock, glacial drift, and coarse lag deposits that contain sediments (where present) ranging from boulder fields to gravelly coarse-to-medium sands. These environments are dominant on the shallow margins of the bay (water depths <30 m) where they reflect sediment resuspension, winnowing, and transport during modern northerly storms. (2) Environments of deposition are blanketed by fine-grained sediments ranging from muds to muddy fine sands. These environments are dominant across the floor of the central basin (water depths= 30-60 m) where fine- grained sediments (derived from regional and local sources and emplaced primarily during episodic wind- and density-driven flow) settle through the water column and accumulate under weak bottom currents during nonstorm conditions. (3) Environments of sediment reworking contain patches with diverse textures ranging from gravelly sands to muds. These environments occupy much of the transitional slopes between the margins and the basin floor and reflect a combination of erosion and deposition. The patchy distribution of sedimentary environments within the bay reflects not only regional changes in processes between the margins and the basin but local changes within each part of the bay as well. Small-scale patchiness is caused by local changes in the strengths of wave- and wind-driven currents and (on the margins) by local

  10. Atlantic coastal plain

    SciTech Connect

    Libby-French, J.; Amato, R.V.

    1981-10-01

    Exploratory drilling in the Atlantic coastal plain region decreased in 1980. Seven wells were drilled, five of which were completed, for a total footage of 80,968 ft (24,679 m). Six of the wells were located in the Baltimore Canyon Trough, and one was located in the Southeast Georgia Embayment. No exploratory wells were drilled in the Georges Bank Basin or in the onshore portion of this region in 1980. Tenneco and Exxon reported gas shows in two wells in the Baltimore Canyon Trough; the remaining completed wells were reported as dry holes. No lease sales were held in 1980, but two sales are scheduled for 1981 in the Middle and South Atlantic. 1 figure, 2 tables.

  11. Extremely halotolerant bacteria characteristic of fully cured and dried cod.

    PubMed

    Vilhelmsson, O; Hafsteinsson, H; Kristjánsson, J K

    1997-05-20

    Gram-positive cocci were isolated in high numbers from salted codfish during processing. They were found to be the main bacterial type in fully cured and dried salted cod. Phenotypic characterization of 37 strains showed them to belong to the novobiocin resistant staphylococci, most likely Staphylococcus arlettae or xylosus. Based on sequencing of 16S rDNA and comparison of 700 bases it was concluded that they should be assigned to the species Staphylococcus arlettae. They were found to be extremely halotolerant, growing well at salt concentrations from 0.06 M NaCl, and even displaying clear growth at 4.5 M NaCl. Likewise, the strains grew over a wide temperature range, from 8 to 45 degrees C. Optimal growth conditions were found to be at 0.4-0.6 M NaCl and 30-32 degrees C. This is all in accordance with findings for related staphylococci that have been isolated from other heavily salted meat or fish products.

  12. Northeast Atlantic bathymetric map

    NASA Astrophysics Data System (ADS)

    Loubrieu, B.; Sibuet, J.-C.; Monti, S.; Mazé, J.-P.

    2003-04-01

    The new bathymetric map of the Bay of Biscay and Northeast Atlantic Ocean is based on all available conventional and multibeam data. It extends from the European coast to the mid-Atlantic ridge in longitude and from the Azores-Gibraltar fracture zone to 50^oN in latitude. Grid spacing is one km. The map is in Mercator projection at a 1/2,400,000 scale. With respect to previously published maps, the detailed morphology of Eurasian and Iberian continental margins, a complete picture of the two fossil trajectories of the Bay of Biscay triple junction, which limit the western extension of the Bay of Biscay, and the precise location of the plate boundary between Eurasia and Iberia, which was active during the Tertiary, are now available. The Bay of Biscay and Northeast Atlantic opened simultaneously between chrons M0 (118 Ma) and 33o (80 Ma). A triple junction existed during that period. Fossil triple junctions trajectories on each of the three Eurasia (EU), Iberia (IB) and North America (NA) plates separate oceanic domains which were formed between the three plate pairs: IB/EU for the Bay of Biscay, EU/NA and IB/NA for the northern and southern portions of the Northeast Atlantic respectively. On each side of the fossil trajectories, rift directions formed between different plate pairs present different azimuths. The two eastern branches have been identified on the basis of available bathymetric, magnetic and seismic data. They are generally associated with a basement ridge whose bathymetric expression is clearly shown in their youngest parts. The intersections of these two fossil trajectories with the base of the continental margins are conjugate points before the opening of the Bay of Biscay, giving an independent constraint for plate reconstructions at M0 time. In a companion poster, we have used the constraints deduced from the new bathymetric map to derive the IB/EU kinematic motions and discuss their consequences on the formation of Pyrenees.

  13. Long term operation of continuous-flow system with enhanced biological phosphorus removal granules at different COD loading.

    PubMed

    Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

    2016-09-01

    In this study, a continuous-flow system with enhanced biological phosphorus removal (EBPR) granules was operated at different COD concentrations (200, 300 and 400mgL(-)(1)) to investigate the effect of COD loading on this system. The results showed that when the COD concentration in influent was increased to 400mgL(-)(1), the anaerobic COD removal efficiency and total phosphorus removal efficiency reduced obviously and the settling ability of granules deteriorated due to the proliferation of filamentous bacteria. Moreover, high COD loading inhibited the EPS secretion and destroyed the stability of granules. Results of high-through pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading. The performance of system, settling ability of granules and proportion of PAOs gradually recovered to the initial level after the COD concentration was reduced to 200mgL(-)(1) on day 81. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Between Localization and Delocalization: Ru(cod)(2+) Units in the Zintl Clusters [Bi9 {Ru(cod)}2 ](3-) and [Tl2 Bi6 {Ru(cod)}](2).

    PubMed

    Lichtenberger, Niels; Spang, Nils; Eichhöfer, Andreas; Dehnen, Stefanie

    2017-08-21

    Reactions of [K(crypt-222)]2 (TlBi3 )⋅0.5 en (1 b) with [Ru(cod)(H2 CC(Me)CH2 )2 ] (A) in 1,2-diaminoethane (en) led to the formation of two compounds with new bismuth-rich cluster anions, [K(crypt-222)]3 [Bi9 {Ru(cod)}2 ]⋅1.5 en (2) and [K(crypt-222)]2 [Tl2 Bi6 {Ru(cod)}]⋅2 tol (3), alongside the salt of a binary nido cluster, [K(crypt-222)]3 (Tl4 Bi5 )⋅2 en (4). The anions in 2 and 3 are two further examples of rare heterometallic clusters containing Ru atoms. As one cod ligand is retained on each Ru atom in both clusters, the anions may be viewed as intermediates on the way towards larger, ligand-free intermetalloid clusters. Quantum-chemical studies provided insight into the bonding situation in these clusters. According to these studies, the anion of 2 features both electron-precise and electron-deficient parts. Electrospray ionization mass spectrometry analysis indicated that the clusters undergo stepwise fragmentation. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Transcriptomic analysis and biomarkers (Rag1 and Igμ) for probing the immune system development in Pacific cod, Gadus macrocephalus.

    PubMed

    Mao, Ming-Guang; Li, Xing; Perálvarez-Marín, Alejandro; Jiang, Jie-Lan; Jiang, Zhi-Qiang; Wen, Shi-Hui; Lü, Hui-Qian

    2015-06-01

    Mortality (>90%) is a big concern in larval rearing facilities of Pacific cod, Gadus macrocephalus, limiting its culture presently still in the experimental stages. Understanding the immune system development of G. macrocephalus is crucial to optimize the aquaculture of this species, to improve the use of economic resources and to avoid abuse of antibiotics. For the transcriptome analysis, using an Illumina sequencing platform, 61,775,698 raw reads were acquired. After a de novo assembly, 77,561 unigenes were obtained. We have classified functionally these transcripts by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). 27 genes mainly related to hematopoietic or lymphoid organ development and somatic diversification of immune receptors have been reported for the first time in Pacific cod, and 14 Ig heavy chain (μ chain) locuses were assembled using Trinity. Based on our previous achievement, we have chosen Rag1 and Igμ as immune system development biomarkers. Full length cDNA of Rag1 and Igμ as biomarkers were obtained respectively using RACE PCR. Concerning Rag1, the deduced amino acid of Rag1 and protein immunodetection revealed a Rag1 isoform of 69 kDa, significantly different from other fish orthologs, such as Oncorhynchus mykiss (121 kDa). Phylogenetic analysis reveals a unique immune system for the Gadus genre, not exclusive for Atlantic cod, among vertebrates. Meanwhile, full length cDNA of Igμ included an ORF of 1710 bp and the deduced amino acid was composed of a leader peptide, a variable domain, CH1, CH2, Hinge, CH3, CH4 and C-terminus, which was in accordance with most teleost. Absolute quantification PCR revealed that significant expression of Rag1 appeared earlier than Igμ, 61 and 95 dph compared to 95 dph, respectively. Here we report the first transcriptomic analysis of G. macrocephalus as the starting point for genetic research on immune system development towards improving the Pacific cod aquaculture. Copyright © 2015

  16. Two Distinct Roles of Atlantic SSTs in ENSO Variability: North Tropical Atlantic SST and Atlantic Nino

    NASA Technical Reports Server (NTRS)

    Ham, Yoo-Geun; Kug, Jong-Seong; Park, Jong-Yeon

    2013-01-01

    Two distinct roles of the Atlantic sea surface temperatures (SSTs), namely, the North Tropical Atlantic (NTA) SST and the Atlantic Nino, on the El Nino-Southern Oscillation (ENSO) variability are investigated using the observational data from 1980 to 2010 and coupled model experiments. It appears that the NTA SST and the Atlantic Nino can be used as two independent predictors for predicting the development of ENSO events in the following season. Furthermore, they are likely to be linked to different types of El Nino events. Specifically, the NTA SST cooling during February, March, and April contributes to the central Pacific warming at the subsequent winter season, while the negative Atlantic Nino event during June, July, and August contributes to enhancing the eastern Pacific warming. The coupled model experiments support these results. With the aid of a lagged inverse relationship, the statistical forecast using two Atlantic indices can successfully predict various ENSO indices.

  17. EPA Signs Two Clean Up Decisions in a Continued Effort to Protect Cape Cod Drinking Water

    EPA Pesticide Factsheets

    In its ongoing efforts to protect the Cape Cod aquifer from contamination from historical military training activities, the U.S. Environmental Protection Agency (EPA) has issued final cleanup strategies for two contaminated areas at Camp Edwards.

  18. [On differentiation of cod (Gadus morhua L.) groups in Baltic Sea].

    PubMed

    2013-09-01

    Using the AGP*, PGI-1*, PGI-2*, LDH*, IDH*, and PGM* allozyme markers, the differentiation of cod groups during the spawning period in Baltic Sea was evaluated. It was shown that cod samples from the eastern and western parts of Baltic Sea (being statistically significantly different from the cod samples from the Norwegian Sea, Barents Sea, and the Skagerrak Strait) demonstrated a high degree of identity (I = 0.99-1.0), which could be associated with the observed from the beginning of the present millennium increased migration of cod from eastern Baltic regions to the waters of Bornholm basin, and the distribution of the part of migrants from Bornholm basin to Arkona basin.

  19. EPA Seeks Public input on Modified Training at Joint Base Cape Cod

    EPA Pesticide Factsheets

    EPA is seeking public comment on a proposed modification to its 1997 order that required the Massachusetts Army National Guard to suspend training activities related to contamination of the Cape Cod Aquifer. Public Meeting Scheduled for Oct. 12.

  20. Environmental toxicology: population modeling of cod larvae shows high sensitivity to loss of zooplankton prey.

    PubMed

    Stige, Leif Christian; Ottersen, Geir; Hjermann, Dag Ø; Dalpadado, Padmini; Jensen, Louise K; Stenseth, Nils Chr

    2011-02-01

    Two factors determine whether pollution is likely to affect a population indirectly through loss of prey: firstly, the sensitivity of the prey to the pollutants, and secondly, the sensitivity of the predator population to loss of prey at the given life stage. We here apply a statistical recruitment model for Northeast Arctic cod to evaluate the sensitivity of cod cohorts to loss of zooplankton prey, for example following an oil spill. The calculations show that cod cohorts are highly sensitive to possible zooplankton biomass reductions in the distribution area of the cod larvae, and point to a need for more knowledge about oil-effects on zooplankton. Our study illustrates how knowledge about population dynamics may guide which indirect effects to consider in environmental impact studies.

  1. 6. Photocopy of woodengraving in Rich, TruroCape Cod facing p. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Photocopy of wood-engraving in Rich, Truro-Cape Cod facing p. 464. Copy owned by Miss Marion Rich, Truro, Mass. SUMMER HOME OF THE AUTHOR, AT LONGNOOK - Shebnah Rich House, Longnook Road, Truro, Barnstable County, MA

  2. Effect of influent COD/SO4(2-) ratios on UASB treatment of a synthetic sulfate-containing wastewater.

    PubMed

    Hu, Yong; Jing, Zhaoqian; Sudo, Yuta; Niu, Qigui; Du, Jingru; Wu, Jiang; Li, Yu-You

    2015-07-01

    The effect of the chemical oxygen demand/sulfate (COD/SO4(2-)) ratio on the anaerobic treatment of synthetic chemical wastewater containing acetate, ethanol, and sulfate, was investigated using a UASB reactor. The experimental results show that at a COD/SO4(2-) ratio of 20 and a COD loading rate of 25.2gCODL(-1)d(-1), a COD removal of as high as 87.8% was maintained. At a COD/SO4(2-) ratio of 0.5 (sulfate concentration 6000mgL(-1)), however, the COD removal was 79.2% and the methane yield was 0.20LCH4gCOD(-1). The conversion of influent COD to methane dropped from 80.5% to 54.4% as the COD/SO4(2-) ratio decreased from 20 to 0.5. At all the COD/SO4(2-) ratios applied, over 79.4% of the total electron flow was utilized by methane-producing archaea (MPA), indicating that methane fermentation was the predominant reaction. The majority of the methane was produced by acetoclastic MPA at high COD/SO4(2-) ratios and both acetoclastic and hydrogenthrophic MPA at low COD/SO4(2-) ratios. Only at low COD/SO4(2-) ratios were SRB species such as Desulfovibrio found to play a key role in ethanol degradation, whereas all the SRB species were found to be incomplete oxidizers at both high and low COD/SO4(2-) ratios.

  3. Change in levels of persistent organic pollutants in human plasma after consumption of a traditional northern Norwegian fish dish-mølje (cod, cod liver, cod liver oil and hard roe).

    PubMed

    Sandanger, Torkjel M; Brustad, Magritt; Lund, Eiliv; Burkow, Ivan C

    2003-02-01

    The traditional northern Norwegian fish dish "mølje", consisting of boiled cod, cod liver, cod liver oil and hard roe, is still consumed frequently during the winter months January to March. The liver of the cod is rich in lipids and the levels of persistent organic pollutants (POPs) are relatively high. To better understand the short-term consequences of this traditional meal on the plasma levels of PCBs and p,p'-DDE, individual intake of liver and cod liver oil during one meal was measured. Blood samples were collected from 33 participants before the meal, and then 4 h, 12 h and 5 days after it. Lipid-weight and wet-weight levels of 10 PCB congeners and p,p'-DDE were determined in the plasma samples and the food. The plasma levels of p,p'-DDE was found to increase significantly from 0 to 4 h, both when expressed as wet-weight (35% change) and lipid-weight (20% change). The corresponding changes (0-4 h) in wet-weight levels of the most prevalent PCB congeners were non significant. By contrast, PCB congeners with low levels in the food showed a significant drop in lipid-weight levels during the first 4 h. The observed changes were independent of amount consumed. Significant differences in fasting and non-fasting samples were found for most PCBs and p,p'-DDE. For the lipid weight levels of sum PCBs there was a significant decrease of 16% from non-fasting to fasting samples. To obtain reliable data on human levels of POPs it is, on the basis of these findings, recommended that blood samples should be collected from fasting individuals and both wet-weight and lipid-weight levels should be reported.

  4. Comparing growth rates of Arctic Cod Boreogadus saida across the Chukchi and Beaufort Seas

    NASA Astrophysics Data System (ADS)

    Frothingham, A. M.; Norcross, B.

    2016-02-01

    Dramatic changes to the Arctic have highlighted the need for a greater understanding of the present ecosystem. Arctic Cod, Boreogadus saida, commonly dominate fish assemblages in the Arctic region and inhabit two geographically unique seas in the U.S. Due to the importance of Arctic Cod in the Arctic food web, establishing current benchmark information such as growth rates, will provide a better understanding as to how the species will adapt to the effects of climate change. To investigate differences in Arctic Cod life history across nearly 1500 km of vital habitat, growth rates were examined using a von Bertalanffy growth equation. Arctic Cod were collected from 2009 to 2014 from the Chukchi and Beaufort seas. Arctic Cod collected from the Chukchi Sea had an overall smaller maximum achievable length (210 mm) compared to the Beaufort Sea (253 mm) despite a larger sample size in the Chukchi Sea (n=1569) than the Beaufort Sea (n=1140). Growth rates indicated faster growth in the Chukchi Sea (K =0.33) than in the Beaufort Sea (K= 0.29). Arctic Cod collected from the Chukchi Sea had similar achievable maximum lengths throughout, but those collected from the southern Chukchi Sea grew at faster rates (K=0.45).Arctic Cod in the eastern Beaufort Sea region had a higher overall maximum achievable length (243 mm) than in the western Beaufort Sea region (186 mm). Knowledge about contemporary growth rates of Arctic Cod in the Chukchi and Beaufort Seas can be used in future comparisons to evaluate potential effects of increasing climate change and anthropogenic influences.

  5. Hepatoprotective effects of cod liver oil against sodium nitrite toxicity in rats.

    PubMed

    Salama, Mohamed F; Abbas, Ahmed; Darweish, Mohamed M; El-Hawwary, Amany A; Al-Gayyar, Mohammed M H

    2013-11-01

    Exposure to high levels of nitrites for a prolonged time have adverse health effects on several organs especially the liver due to oxidative properties. Meanwhile, cod liver oil has been reported to ameliorate organ dysfunction in animal models that involve oxidative stress. Examine the impact of dietary cod liver oil on sodium nitrite-induced liver damage. Thirty-two adult male Sprague-Dawely rats were daily treated with sodium nitrite (80 mg/kg) in presence or absence of cod liver oil (5 ml/kg). Morphological changes were assessed in liver sections. Oxidative stress and antioxidant markers were measured in serum and liver homogenates. Liver samples were used for measurements of MCP-1, DNA fragmentation and mitochondrial function. The hepatoprotective effect of cod liver oil was proved by significant reduction of elevated liver enzymes and normal appearance of hepatocytes. Cod liver oil significantly reduced hepatic malondialdehyde, hydrogen peroxide and superoxide anion (224.3 ± 18.9 nmol/g, 59.3 ± 5.1 and 62.5 ± 5.1 µmol/g, respectively) compared with sodium nitrite (332.5 ± 25.5 nmol/g, 83.1 ± 8.1 and 93.9 ± 6.5 µmol/g, respectively). Cod liver oil restored hepatic cytochrome c oxidase activity after 38% reduction by sodium nitrite. Furthermore, cod liver oil significantly reduced hepatic MCP-1 (79.8 pg/mg) and DNA fragmentation (13.8%) compared with sodium nitrite (168.7 pg/mg and 41.3%, respectively). Cod liver oil ameliorates sodium nitrite induced hepatic impairment through several mechanisms including attenuation of oxidative stress, blocking MCP-1, reactivation of mitochondrial function and reduction of DNA fragmentation.

  6. Historic changes in length distributions of three Baltic cod (Gadus morhua) stocks: Evidence of growth retardation.

    PubMed

    Svedäng, Henrik; Hornborg, Sara

    2017-08-01

    Understanding how combinations of fishing effort and selectivity affect productivity is central to fisheries research. We investigate the roles of fishing regulation in comparison with ecosystem status for Baltic Sea cod stock productivity, growth performance, and population stability. This case study is interesting because three cod populations with different exploitation patterns and stock status are located in three adjacent but partially, ecologically different areas. In assessing stock status, growth, and productivity, we use survey information and rather basic stock parameters without relying on age readings. Because there is an urgent interest of better understanding of the current development of the Eastern Baltic cod stock, we argue that our approach represents partly a novel way of interpreting monitoring information together with catch data in a simplified yet more informative way. Our study reports how the Eastern and Western Baltic cod have gone toward more truncated size structures between 1991 and 2016, in particular for the Eastern Baltic cod, whereas the Öresund cod show no trend. We suggest that selective fishing may disrupt fish population dynamic stability and that lower natural productivity might amplify the effects of selective fishing. In support of earlier findings on a density-dependent growth of Eastern Baltic cod, management is advised to acknowledge that sustainable exploitation levels for Eastern Baltic cod are much more limited than perceived in regular assessments. Of more general importance, our results emphasize the need to embrace a more realistic view on what ecosystems can produce regarding tractable fish biomass to facilitate a more ecosystem-based fisheries management.

  7. Performance of COD removal from oxide chemical mechanical polishing wastewater using iron electrocoagulation.

    PubMed

    Wang, Chih-Ta; Chou, Wei-Lung

    2009-10-01

    This study investigated the feasibility of chemical oxygen demand (COD) abatement from oxide chemical mechanical polishing (oxide-CMP) wastewater. The process variables, including applied voltage, electrolyte concentration and temperature, were evaluated in terms of COD removal efficiency. In addition, the effects of applied voltage, supporting electrolyte, and temperature on electric energy consumption were evaluated. Under the optimum balance of variables, satisfactory COD removal efficiency and relatively low energy consumption were achieved. The optimum electrolyte concentration, applied voltage, and temperature were found to be 200 mg/L NaCl, 20 V, and 25 degrees C, respectively. Under these conditions, the COD concentration in oxide-CMP wastewater decreased by more than 90%, resulting a final wastewater COD concentration that was below the Taiwan discharge standard (100 mg/L). Since the processed wastewater quality exceeded the direct discharge standard, the effluent could be considered for reuse. COD removal rates obtained during the electrocoagulation process can be described using a pseudo-kinetic model. The present study results show that the kinetic data fit the pseudo first-order kinetic model well. Finally, the morphology and composition of the sludge produced were characterized using scanning electron microscopy (SEM) and energy dispersion spectra (EDS).