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Mackerel
Kinds of Mackerel Terms modified by Mackerel Selected AbstractsEFFECT OF ARTIFICIAL FEEDING ON DIGESTIVE EFFICIENCY, GROWTH AND QUALITIES OF MUSCLE AND OOCYTE OF MATURING ATLANTIC MACKEREL (SCOMBER SCOMBRUS L.)JOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2007KRISNA RUNGRUANGSAK-TORRISSEN ABSTRACT Maturing Atlantic mackerel with and without artificial feeding, kept in sea pens (September to May), showed differences in digestive efficiency (protease activity ratio of trypsin to chymotrypsin), muscle growth (concentrations of RNA, protein, RNA/protein ratio and free amino acids [FAA]) and oocyte quality (trypsin-like specific activity, and concentrations of RNA, RNA/protein ratio and FAA). The artificially fed mackerel had higher body weights (1.7 times) but with less white muscle protein concentration (0.5 time), compared to the control group. Both groups showed higher levels of capacity for protein synthesis in the oocytes than in the white muscle, but it was about two times higher in the artificially fed fish whereas about four times higher in the control group. This indicated that, during maturation, development of oocytes and muscle for growth occurred concurrently in higher growth mackerel, while development of oocytes dominated in slower growth fish. A higher trypsin-like specific activity with higher FAA levels in the oocytes from females fed with an artificial diet, compared to the control group, suggested differences in development and quality between the gametes of the fish with different feedings. PRACTICAL APPLICATIONS The work illustrates differences in digestive efficiency and the quality of growth performance (growth and protein metabolism in muscle and oocytes) in fish with different feedings. The use of various methods for evaluating digestive efficiency and the quality of fish growth performance could provide reasonable information for some important biological differences between fish groups, especially when the number of samples are low. It is more advantageous to apply different methods simultaneously than using growth parameter alone in order to study for precise evaluation of the quality of fish growth performance. The methods are very practical for studying food utilization and growth quality of fish in different environmental conditions and with different behaviors in aquaculture as well as in natural ecosystem where food consumption rate and feeding regime cannot be under control. [source] BACTERIAL FORMATION OF HISTAMINE IN JACK MACKEREL (TRACHURUS SYMMETRICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2004A. BERMEJO ABSTRACT Peak histamine concentrations of 0.023, 0.031 and 0.027 g histamine/100 g muscle and maximal bacteria concentrations of 1.75, 1.59 and 0.423 g dry cells/100 g muscle were observed in muscles of jack mackerel stored at 25, 15 and 5C, respectively. Incubated fish homogenates suggest rate and transport limitations in histamine formation in muscle. The Mulchandani model predicted bacterial growth in muscle. The Luedeking and Piret expression fitted histamine formation in muscle; , values were 3.0 × 10,3, 1.23 × 10,2 and 4.17 × 10,2 g histamine/g dry cells, while ,-values were 4.5 × 104, 8.0 × 10,5 and 0 g histamine/g dry cells × h at 25, 15, and 5C, respectively. The model predicts that jack mackerel could be stored from 4.5 to 5.5 days in ice, from 1 to 2 days at 15C and from 17 h to 2 days at 25C before fishmeal quality might be affected. [source] GROWTH AND CHARACTERIZATION OF THE HISTAMINE-FORMING BACTERIA OF JACK MACKEREL (TRACHURUS SYMMETRICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2003ALINA BERMEJO ABSTRACT Consumption of fish with high histamine poses health hazards. The isolation, identification and viable counts of the histamine-forming bacteria from jack mackerel in batch cultures in trypticase soy broth with 2 % histidine at 25, 15 and 5C were performed. Proteus vulgaris, Aeromonas hydrophila and Photobacterium damsela were the most histamine producing population. The community had a maximal specific growth rate (,max) of 0.304, 0.217 and 0.048 h,1 at 25, 15 and 5C, respectively. Mulchandani's model, with an exponential value of 5.21, predicted bacterial growth. Histamine production was proportional to growth rate; proportionality coefficients were 1.987, 0.436 and 1.439 and the community's maximal spefic rates for histamine production were 0.604, 0.095 and 0.068 [g histamine (g dry cells h),1] af 25, 15 and SC, respectively. Lesser histamine production at 15C needs further investigation in whole fish, as it is a relevant result forfish handling. [source] Diel variation in feeding rate and prey composition of herring and mackerel in the southern Gulf of St LawrenceJOURNAL OF FISH BIOLOGY, Issue 5 2003E. Darbyson Diel feeding patterns of herring Clupea harengus and mackerel Scomber scombrus in the southern Gulf of St Lawrence were examined based on samples obtained by midwater trawling between 19 and 26 June 2001. Within 3 h time periods, stomach contents tended to be more similar between fish from the same tow than between fish from different tows. Thus, in contrast to previous diet studies, which have used individual fish stomachs as independent observations, tow was used as the experimental unit in statistical analyses in this study. Diel patterns in stomach fullness were identified using generalized additive models. Two peaks in stomach fullness occurred for herring, one in the morning and the other in the evening. Mackerel showed an increase in feeding intensity throughout the day with a peak in mid-afternoon. The diel changes in stomach contents suggested rapid gastric evacuation rates for both species, especially for herring. The estimate of the instantaneous evacuation rate for herring was twice that for mackerel. Calanus copepods (mainly C. hyperboreus), fishes (mainly capelin Mallotus villosus) and euphausiids were the main prey found in the stomachs of both species. Calanus copepods dominated the diet of herring regardless of time period. They also dominated the diet of mackerel during the late afternoon, evening and night while fishes and euphausiids were dominant during the morning and early afternoon. These diel patterns emphasize the need for sampling throughout the day and night in order to estimate ration and diet composition for bioenergetic and ecosystem models. [source] Effect of Combining Proteolysis and Lactic Acid Bacterial Fermentation on the Characteristics of Minced MackerelJOURNAL OF FOOD SCIENCE, Issue 3 2005Li-Jung Yin ABSTRACT: To improve the quality of fish muscle, mackerel muscle protein was hydrolyzed by proteases from Aspergillus oryzae, and then fermented by lactic acid bacteria (LAB). The highest protease activities were obtained from A. oryzae after 72 h incubation at 25°C. Acidic protease activity was much higher than neutral and alkaline proteases. SDS-PAGE indicated the degradation of muscle proteins after 1 or 2 h hydrolysis by A. oryzae proteases at 50°C. During 48 h fermentation by Pediococcus pentosaceus L and S at 37°C, rapid growth of LAB, decline in pH, and suppression in the growth of microflora, Enterobacteriaceae, Staphylococcus, and Pseudomonas, occurred while increases in whiteness, nonprotein nitrogen, sensory quality, and free amino acids were observed. These data suggested that the acceptability of LAB -fermented mackerel hydrolysates could be substantially improved. [source] The Physicochemical Quality Characteristics of Charcoal Grilled MackerelsJOURNAL OF FOOD SCIENCE, Issue 3 2002M-Y. Kim ABSTRACT: : The effects of different fuel sources used in grilling on the physicochemical and sensory characteristics of mackerel were investigated. Oak and sawdust charcoals were used as fuel sources. The content of saturated fatty acids was increased during grilling. Histidine was the most predominant amino acid; grilling significantly increased glutamic acid. Mackerel shows a high inosine 5,-monophosphate content that is increased during grilling. Oak charcoal and sawdust charcoal contained high levels of potassium and sodium, respectively. Potassium content was increased at the surface muscle of oak charcoal grilled mackerel (OM). The flavor preference for OM was significantly (p < 0.05%) higher than for sawdust charcoal grilled mackerel. These results indicate that physicochemical and sensory properties of grilled foods can be affected by the fuel source. [source] A diet enriched with mackerel (Scomber scombrus),derived products improves the endothelial function in a senior population (Prevención de las Enfermedades Cardiovasculares: Estudio Santoña , PECES project)EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2009J. R. De Berrazueta ABSTRACT Background, Regular consumption of fish reduces cardiovascular risks. Here, we investigate if the consumption of products with mackerel (Scomber scombrus) with 8·82 g of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) content per 100 g of product improves parameters of endothelial function in a controlled population. Materials and methods, Subjects maintained a 12-week diet with products with mackerel. The population consisted of 58 senior subjects (12 withdrawals, 25 women), aged 82·08 ± 8·13 years (Group A). Twenty-three senior subjects (13 women) on a regular diet were used as the control group (Group B). Subjects of Group A received 57 portions throughout 12 weeks (four to five portions a week of products with a mean EPA + DHA content of 2·5 g a day). A continuous follow-up and a final evaluation were performed to determine the level of consumption. Plasma samples were stored at ,70 °C for a biochemical study. Endothelial function was analysed by reactive hyperemia with a mercury strain gauge plethysmography with measurement of blood flow in the forearm, both baseline and at the end of the 12-week diet. Results, Endothelium-dependent vasodilatation significantly increased in Group A subjects (P < 0·001). No changes were found in Group B. The subgroup analyses showed that improvements were produced in Group A subjects without cardiovascular disease (P < 0·001). Nitrites/nitrates and von Willebrand factor plasma concentrations were higher in participants after the 12-week diet. Conclusions, The consumption of mackerel meat products improves endothelium-dependent, flow-mediated vasodilatation in a senior population. This finding might explain some of the cardioprotective effects of fish consumption. [source] Fatty acid composition of selected roes from some marine speciesEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 9 2009Miguel Ángel Rincón-Cervera Abstract Fifteen roes from different marine fish species available in Spain were analyzed in order to determine their fatty acid (FA) composition, especially the eicosapentaenoic acid (20:5n -3, EPA) and docosahexaenoic acid (22:6n -3, DHA) contents. Roes from Atlantic bonito (Sarda sarda), European squid (Loligo vulgaris), cuttlefish (Sepia spp.), lumpfish (Cyclopterus lumpus), European hake (Merluccius merluccius), Atlantic salmon (Salmo salar) and gonads of male Atlantic mackerel (Scomber scombrus) reached EPA + DHA amounts higher than 30% of the total FA, and among them, roes from lumpfish, European hake and salmon provide different FA type ratios that could make them adequate as dietary sources of EPA and DHA. [source] Ichthyoplankton-based spawning dynamics of blue mackerel (Scomber australasicus) in south-eastern Australia: links to the East Australian CurrentFISHERIES OCEANOGRAPHY, Issue 4 2008FRANCISCO J. NEIRA Abstract We describe findings of three ichthyoplankton surveys undertaken along south-eastern Australia during spring (October 2002, 2003) and winter (July 2004) to examine spawning habitat and dynamics of blue mackerel (Scomber australasicus). Surveys covered ,860 nautical miles between southern Queensland (Qld; 24.6°S) and southern New South Wales (NSW; 41.7°S), and were mainly centred on the outer shelf including the shelf break. Egg identifications were verified applying mtDNA barcoding techniques. Eggs (n = 2971) and larvae (n = 727; 94% preflexion) occurred both in spring and winter, and were confined to 25.0,34.6°S. Greatest abundances (numbers per 10 m2) of eggs (1214,7390) and larvae (437,1172) occurred within 10 nm shoreward from the break in northern NSW. Quotient analyses on egg abundances revealed that spawning is closely linked to a combination of bathymetric and hydrographic factors, with the outer shelf as preferred spawning area, in waters 100,125 m deep with mean temperatures of 19,20°C. Eggs and larvae in spring occurred in waters of the East Australian Current (EAC; 20.6,22.3°C) and mixed (MIX; 18.5,19.8°C) waters, with none occurring further south in the Tasman Sea (TAS; 16.0,17.0°C). Results indicate that at least some of the south-eastern Australian blue mackerel stock spawns during winter-spring between southern Qld and northern NSW, and that no spawning takes place south of 34.6°S due to low temperatures (<17°C). Spawning is linked to the EAC intrusion, which also facilitates the southward transport of eggs and larvae. Since spring peak egg abundances came from where the EAC deflects offshore, eggs and larvae are possibly being advected eastwards along this deflection front. This proposition is discussed based on recent data on blue mackerel larvae found apparently entrained along the Tasman Front. [source] Environmental effects on recruitment and productivity of Japanese sardine Sardinops melanostictus and chub mackerel Scomber japonicus with recommendations for managementFISHERIES OCEANOGRAPHY, Issue 4 2005AKIHIKO YATSU Abstract We compared a wide range of environmental data with measures of recruitment and stock production for Japanese sardine Sardinops melanostictus and chub mackerel Scomber japonicus to examine factors potentially responsible for fishery regimes (periods of high or low recruitment and productivity). Environmental factors fall into two groups based on principal component analyses. The first principal component group was determined by the Pacific Decadal Oscillation Index and was dominated by variables associated with the Southern Oscillation Index and Kuroshio Sverdrup transport. The second was led by the Arctic Oscillation and dominated by variables associated with Kuroshio geostrophic transport. Instantaneous surplus production rates (ISPR) and log recruitment residuals (LNRR) changed within several years of environmental regime shifts and then stabilized due, we hypothesize, to rapid changes in carrying capacity and relaxation of density dependent effects. Like ISPR, LNRR appears more useful than fluctuation in commercial catch data for identifying the onset of fishery regime shifts. The extended Ricker models indicate spawning stock biomass and sea surface temperatures (SST) affect recruitment of sardine while spawning stock biomass, SST and sardine biomass affect recruitment of chub mackerel. Environmental conditions were favorable for sardine during 1969,87 and unfavorable during 1951,67 and after 1988. There were apparent shifts from favorable to unfavorable conditions for chub mackerel during 1976,77 and 1985,88, and from unfavorable to favorable during 1969,70 and 1988,92. Environmental effects on recruitment and surplus production are important but fishing effects are also influential. For example, chub mackerel may have shifted into a new favorable fishery regime in 1992 if fishing mortality had been lower. We suggest that managers consider to shift fishing effort in response to the changing stock productivity, and protect strong year classes by which we may detect new favorable regimes. [source] An individual-based model of the early life history of mackerel (Scomber scombrus) in the eastern North Atlantic, simulating transport, growth and mortalityFISHERIES OCEANOGRAPHY, Issue 6 2004J. Bartsch Abstract The main purpose of this paper is to provide the core description of the modelling exercise within the Shelf Edge Advection Mortality And Recruitment (SEAMAR) programme. An individual-based model (IBM) was developed for the prediction of year-to-year survival of the early life-history stages of mackerel (Scomber scombrus) in the eastern North Atlantic. The IBM is one of two components of the model system. The first component is a circulation model to provide physical input data for the IBM. The circulation model is a geographical variant of the HAMburg Shelf Ocean Model (HAMSOM). The second component is the IBM, which is an i-space configuration model in which large numbers of individuals are followed as discrete entities to simulate the transport, growth and mortality of mackerel eggs, larvae and post-larvae. Larval and post-larval growth is modelled as a function of length, temperature and food distribution; mortality is modelled as a function of length and absolute growth rate. Each particle is considered as a super-individual representing 106 eggs at the outset of the simulation, and then declining according to the mortality function. Simulations were carried out for the years 1998,2000. Results showed concentrations of particles at Porcupine Bank and the adjacent Irish shelf, along the Celtic Sea shelf-edge, and in the southern Bay of Biscay. High survival was observed only at Porcupine and the adjacent shelf areas, and, more patchily, around the coastal margin of Biscay. The low survival along the shelf-edge of the Celtic Sea was due to the consistently low estimates of food availability in that area. [source] Simulation of mackerel (Scomber scombrus) recruitment with an individual-based model and comparison with field dataFISHERIES OCEANOGRAPHY, Issue 6 2004J. Bartsch Abstract An individual-based model (IBM) for the simulation of year-to-year survival during the early life-history stages of the north-east Atlantic stock of mackerel (Scomber scombrus) was developed within the EU funded Shelf-Edge Advection, Mortality and Recruitment (SEAMAR) programme. The IBM included transport, growth and survival and was used to track the passive movement of mackerel eggs, larvae and post-larvae and determine their distribution and abundance after approximately 2 months of drift. One of the main outputs from the IBM, namely distributions and numbers of surviving post-larvae, are compared with field data as recruit (age-0/age-1 juveniles) distribution and abundance for the years 1998, 1999 and 2000. The juvenile distributions show more inter-annual and spatial variability than the modelled distributions of survivors; this may be due to the restriction of using the same initial egg distribution for all 3 yr of simulation. The IBM simulations indicate two main recruitment areas for the north-east Atlantic stock of mackerel, these being Porcupine Bank and the south-eastern Bay of Biscay. These areas correspond to areas of high juvenile catches, although the juveniles generally have a more widespread distribution than the model simulations. The best agreement between modelled data and field data for distribution (juveniles and model survivors) is for the year 1998. The juvenile catches in different representative nursery areas are totalled to give a field abundance index (FAI). This index is compared with a model survivor index (MSI) which is calculated from the total of survivors for the whole spawning season. The MSI compares favourably with the FAI for 1998 and 1999 but not for 2000; in this year, juvenile catches dropped sharply compared with the previous years but there was no equivalent drop in modelled survivors. [source] Transport of larval jack mackerel (Trachurus japonicus) estimated from trajectories of satellite-tracked drifters and advective velocity fields obtained from sequential satellite thermal images in the eastern East China SeaFISHERIES OCEANOGRAPHY, Issue 6 2002Hee-Yong Kim Abstract Transport processes of jack mackerel (Trachurus japonicus) larvae in the waters off the west coast of Kyushu in the eastern East China Sea, have been investigated using satellite-tracked surface drifters and consecutive satellite thermal images. Trajectories of drifters describe northward flows over the continental shelf, eastward flows of the Kuroshio south-west of Kyushu, and a weak clockwise gyre off the west coast of Kyushu. In particular, the clockwise gyre causes the entrainment of jack mackerel larvae into the waters off the west coast of Kyushu. Consecutive satellite thermal images help to elucidate the northward warm water intrusion from the Kuroshio front south-west of Kyushu. Particle trajectories using sea surface current fields computed with the Maximum Cross Correlation (MCC) technique also reveal that the transport of jack mackerel larvae into the nursery ground off the west coast of Kyushu caused by the anti-cyclonic gyre and the warm streamers are an important process for successful recruitment. [source] Blue fish burgers: nutritional characterisation and sensory optimisationINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2009Rossella Di Monaco Summary In order to reduce waste of marine resources, valorise fishing discards and move towards fish consumption, a new ready-to-cook seafood product was developed. In particular, a chemical investigation on chub mackerel and hake was conducted to the aim of mixing the two fish species to produce nutritionally balanced fish burgers. In addition, to evaluate consumer opinion about these new fresh products and best acceptability of different proportions of mackerel and hake, focus group interviews and consumer test were also performed. The results of the chemical analyses achieved on both selected fish species gave rise to minimally processed fish products with a high amount of chub mackerel, therefore providing the desired nutritional properties and low level of hake in order to obtain firmer and wetter burgers. By means of focus group interviews, the novelty and high level of convenience of the developed fresh commodity was highlighted. Consumer test declared that the most successful sample was that with 70% chub mackerel and 30% hake. [source] Anti-oxidant activity of added tea catechins on lipid oxidation of raw minced red meat, poultry and fish muscleINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2001Shuze Tang The comparative anti-oxidative effects of added tea catechins (TC) and ,-tocopherol to raw minced red meat (beef and pork), poultry (chicken, duck and ostrich) and fish (whiting and mackerel) muscle on susceptibility to lipid oxidation were investigated during 10 days of refrigerated (4 °C) display. Fresh meats, poultry and fish, purchased from a local market, were trimmed to remove bones, skin and surface fat and minced through a 4 mm plate. The minced muscle of each species was treated with either the addition of 300 mg TC kg,1 minced muscle (TC300) or 300 mg ,-tocopherol kg,1 minced muscle (VE300). Minced muscle without any additives served as control (C). Oxidative stability (TBARS) was measured at 3-day intervals. Total lipids, fatty acid composition, total iron and haem iron from minced muscle for each species were also analysed. The susceptibility of untreated minced muscle to lipid oxidation was in the decreasing order: mackerel > beef > duck > ostrich > pork , chicken > whiting. This may be because of the different content of total fat, iron and fatty acid composition between species. The TC300 significantly (P < 0.05) reduced lipid oxidation compared with controls for all seven species as shown by lower TBARS values. The anti-oxidant potential of TC was two to fourfold greater than that of ,-tocopherol at the same concentration and this potential was species dependent. The VE300 showed limited capacity in inhibiting lipid oxidation for pork, chicken, duck and whiting. The results obtained show that TCs are powerful natural antioxidants when used in minced muscle food. [source] Food habits of the silky shark Carcharhinus falciformis (Müller & Henle, 1839) off the western coast of Baja California Sur, MexicoJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2010A. A. Cabrera-Chávez-Costa Summary The objective of this study was to establish the trophic niche of the silky shark and to determine the ecological role of this predator in the ecosystem close to Baja California. The trophic spectrum was analyzed from samples taken during summer and autumn (2000,2002) from the fishing camps of Punta Lobos and Punta Belcher on the western coast of Baja California Sur. A total of 263 stomach contents were analyzed (143 with food; 120 empty). The index of relative importance (IRI) showed that at Punta Lobos, silky sharks fed mainly on red crabs Pleuroncodes planipes (%IRI = 83%), whereas at Punta Belcher the main food item was the jumbo squid Dosidicus gigas (%IRI = 41%), followed by chub mackerel Scomber japonicus (%IRI = 33%). According to the Levin Index (Bi), the trophic niche breadth in silky sharks is low (Bi = <0.6), which means that silky sharks are specialist predators because they mainly consume three prey types: red crab, chub mackerel, and jumbo squid. The Shannon-Wiener Index indicated that all trophic categories at Punta Belcher (0.85,1.22) had lower diversity than at Punta Lobos (0.50,1.6), because the silky shark feeds more on tropical prey found close to Punta Lobos. The Morisita-Horn Index (C,) showed an overlap in the diet between the two areas analyzed and between sexes (C, = >0.6). The juveniles and adult females did not show any overlap. In the caloric analysis of the main prey, the jumbo squid (D. gigas) contributed the most calories to the silky shark diet (76%). [source] An interdisciplinary evaluation of fishery production systems off the state of Pará in North BrazilJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2009V. J. Isaac Summary The performance of 20 fishery production systems off the state of Pará in the northern region of Brazil was compared using the ,RAPFISH' methodology, with 57 identified attributes distributed among five evaluation fields: economics, sociology, ecology, technology and politics. The results indicated the existence of three large groups of fishery sectors: (i) industrial (red snapper with traps, the Laulao catfish, shrimp trawl) and semi-industrial (lobster) fisheries; (ii) large-scale artisanal fisheries (acoupa weakfish, red snapper with lines, king mackerel, Spanish mackerel, coco sea catfish); and (iii) small-scale artisanal fisheries (shellfish, crab, estuarine longline, fish traps, etc.). While the industrial and large-scale artisanal systems demonstrated greater sustainability from an economic and social standpoint, small-scale fisheries appeared to be more ecologically sustainable. Based on the results, a reduction in industrial fishing efforts is recommended, along with the establishment of licensing quotas for fishing vessels, as well as an increased investment in research on proper guidance and management of the semi-industrial and large-scale artisanal fisheries sectors. For small-scale artisanal fisheries, economic incentives are suggested for the aggregate value of the products and to assist fishers in the development of an appropriate social organization. Finally, it is believed that a greater stakeholder involvement in the decision-making process would improve management actions for all modalities. [source] Genetic differentiation of Mediterranean horse mackerel (Trachurus mediterraneus) populations as revealed by mtDNA PCR-RFLP analysisJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2009By C. Turan Summary The genetic population structure of Mediterranean horse mackerel, Trachurus mediterraneus, from seven locations throughout the Black, Marmara, Aegean and eastern Mediterranean seas was investigated using restriction fragment length polymorphism (RFLP) analysis of the mtDNA 16S rDNA region. An approximately 2000-bp segment was screened in 280 individuals using six restriction enzymes, resulting in 10 composite haplotypes. The most common haplotype was present in 56.42% individuals; the next most frequent haplotype was present in 22.85% individuals. Average haplotype diversity within samples was moderate (0.38), and nucleotide diversity was low (0.00435). Mean nucleotide divergence for the seven sampling sites was 0.0028. Nucleotide divergence among samples was moderate, with the highest value detected between the Aegean Sea (Izmir) and the eastern Black Sea (Trabzon) populations (0.007055), and the lowest (,0.000043) between the Marmara Sea (Adalar) and the western Black Sea (Sile) populations. In Monte Carlo pairwise comparisons of haplotype frequencies, the Sinop from the middle Black Sea, Trabzon from the eastern Black Sea, and Iskenderun Bay from the north-eastern Mediterranean Sea exhibited highly significant (P < 0.001) geographical differentiation from each other and from all other populations. Mantel's test indicated that the nucleotide divergence among populations of T. mediterraneus was not significantly associated with their geographical isolation (r = ,0.2963; P > 0.05). Consequently, the mtDNA 16S rDNA region provided evidence for the existence of three distinct T. mediterraneus populations (Sinop, Trabzon and Iskenderun Bay) in the Black and north-eastern Mediterranean seas. [source] The diet of blue whiting, hake, horse mackerel and mackerel off PortugalJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2002H. N. Cabral This paper deals with the diets of blue whiting Micromesistius poutassou (Risso 1810), hake Merluccius merluccius (L. 1758), horse mackerel Trachurus trachurus (L. 1758), and mackerel Scomber scombrus (L. 1758) off Portugal and explores variations in fish length, water depth, latitude and season. All four species feed on fish; however, hake and mackerel are the first and second most important predators, respectively, blue whiting being the most important fish prey for both species. The diets of blue whiting and horse mackerel are composed mainly of crustaceans. Diet variations according to predator fish size are more important than either latitude or depth. In the diets of blue whiting, hake and horse mackerel, prey importance increases with predator size. For blue whiting and horse mackerel, diet variations with fish length and water depth are correlated: small fish are closely associated with coastal areas where they feed on copepods and decapod larvae. Seasonality in the diet is apparent for blue whiting, hake and mackerel. For blue whiting, the decapod Pasiphaea sivado is the most important prey in summer and autumn, being replaced by the euphausid Meganyctiphanes norvegica in winter. In the diet of hake, seasonality was characterised by the major importance of Macroramphosus scolopax in autumn, whereas the diet of mackerel consisted of zooplankton in summer, fish and decapods in autumn and decapod larvae in winter. Seasonal changes in the diet of horse mackerel correspond to a higher diversity of prey in autumn compared to other seasons (although euphausids are the main prey in all seasons). Seasonality in feeding activity is not as marked for the other species as it is for horse mackerel; the percentage of empty stomachs of horse mackerel is greatest in winter, when spawning takes place at the Portuguese coast. [source] A comparison of gut evacuation models for larval mackerel (Scomber scombrus) using serial photographyJOURNAL OF FISH BIOLOGY, Issue 4 2009R. Dunbrack A novel technique is described, using serial photography of the gut contents of transparent living larval fishes, to generate individual gut evacuation time series. This technique was applied to Atlantic mackerel Scomber scombrus larvae to compare three widely used models of gut evacuation: linear, exponential and square-root. Regression r2 for the exponential model exceeded those for the linear and square root models in 20 of 21 time series, strongly supporting the exponential model. At the initial gut fullness for each time series, total gut evacuation rates calculated with the exponential model averaged 2·2 and 1·3 times greater than those calculated with the linear and square-root models, respectively, and would produce correspondingly higher estimates of feeding rates for field-collected larvae with similar levels of gut fullness. The results highlight the importance of choosing the appropriate evacuation model in feeding studies, particularly those intended to examine short-term changes in larval fish feeding rates, a contributing factor to the highly variable yearly recruitment of many marine fish species. [source] Diel variation in feeding rate and prey composition of herring and mackerel in the southern Gulf of St LawrenceJOURNAL OF FISH BIOLOGY, Issue 5 2003E. Darbyson Diel feeding patterns of herring Clupea harengus and mackerel Scomber scombrus in the southern Gulf of St Lawrence were examined based on samples obtained by midwater trawling between 19 and 26 June 2001. Within 3 h time periods, stomach contents tended to be more similar between fish from the same tow than between fish from different tows. Thus, in contrast to previous diet studies, which have used individual fish stomachs as independent observations, tow was used as the experimental unit in statistical analyses in this study. Diel patterns in stomach fullness were identified using generalized additive models. Two peaks in stomach fullness occurred for herring, one in the morning and the other in the evening. Mackerel showed an increase in feeding intensity throughout the day with a peak in mid-afternoon. The diel changes in stomach contents suggested rapid gastric evacuation rates for both species, especially for herring. The estimate of the instantaneous evacuation rate for herring was twice that for mackerel. Calanus copepods (mainly C. hyperboreus), fishes (mainly capelin Mallotus villosus) and euphausiids were the main prey found in the stomachs of both species. Calanus copepods dominated the diet of herring regardless of time period. They also dominated the diet of mackerel during the late afternoon, evening and night while fishes and euphausiids were dominant during the morning and early afternoon. These diel patterns emphasize the need for sampling throughout the day and night in order to estimate ration and diet composition for bioenergetic and ecosystem models. [source] Effect of body size on the standard metabolism of horse mackerelJOURNAL OF FISH BIOLOGY, Issue 3 2000J-P. Herrmann The routine metabolic rate RR and standard metabolic rate RS were measured in horse mackerel Trachurus trachurus at 13°C over weight range of 1·4,390 g. A data extraction method rather than the more commonly used method of extrapolating the swimming speed-metabolic rate curves back to zero swimming speed was developed to measure the RS. The relation between RR and RS and weight was expressed as a linear regression with the log transformed data. The mean slope of the regression was 0·752 for RS and 0·725 for RS. [source] Hepatic coccidiosis of the blue whiting, Micromesistius poutassou (Risso), and horse mackerel, Trachurus trachurus (L.), from Galician watersJOURNAL OF FISH DISEASES, Issue 6 2001E Abollo The aetiology, epidemiology and pathology of coccidiosis in commercially-exploited populations of Micromesistius poutassou and Trachurus trachurus from Galician waters were investigated. Sporogonic stages of Goussia clupearum and G. cruciata were found in the liver. Although the descriptive statistics of Goussia infrapopulations and demographic infection values were always higher in M. poutassou than in T. trachurus, parasite distribution was highly skewed for both coccidian species. In both fish species, the number of oöcysts showed a similar cumulative effect as parasite counts increased with increasing length and weight of fish, but did not change with host sex or sexual maturity. Pathological changes in infected liver parenchyma of both species were moderate (in T. trachurus) to severe (in M. poutassou), with greatly reduced livers in the most heavily infected fish. Large areas of liver tissue were replaced with oöcysts. Host response to infection included the formation of a fibrous capsule prior to infiltration by melanin and lymphocytes. Although post-recruit individuals of both fish species apparently tolerate a severe infection, there was statistical evidence of a serious contribution by the parasite to poor body condition in M. poutassou shown by changes in the hepatosomatic and K-Fulton indices and in the length- to-weight relationship. [source] EFFECT OF ARTIFICIAL FEEDING ON DIGESTIVE EFFICIENCY, GROWTH AND QUALITIES OF MUSCLE AND OOCYTE OF MATURING ATLANTIC MACKEREL (SCOMBER SCOMBRUS L.)JOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2007KRISNA RUNGRUANGSAK-TORRISSEN ABSTRACT Maturing Atlantic mackerel with and without artificial feeding, kept in sea pens (September to May), showed differences in digestive efficiency (protease activity ratio of trypsin to chymotrypsin), muscle growth (concentrations of RNA, protein, RNA/protein ratio and free amino acids [FAA]) and oocyte quality (trypsin-like specific activity, and concentrations of RNA, RNA/protein ratio and FAA). The artificially fed mackerel had higher body weights (1.7 times) but with less white muscle protein concentration (0.5 time), compared to the control group. Both groups showed higher levels of capacity for protein synthesis in the oocytes than in the white muscle, but it was about two times higher in the artificially fed fish whereas about four times higher in the control group. This indicated that, during maturation, development of oocytes and muscle for growth occurred concurrently in higher growth mackerel, while development of oocytes dominated in slower growth fish. A higher trypsin-like specific activity with higher FAA levels in the oocytes from females fed with an artificial diet, compared to the control group, suggested differences in development and quality between the gametes of the fish with different feedings. PRACTICAL APPLICATIONS The work illustrates differences in digestive efficiency and the quality of growth performance (growth and protein metabolism in muscle and oocytes) in fish with different feedings. The use of various methods for evaluating digestive efficiency and the quality of fish growth performance could provide reasonable information for some important biological differences between fish groups, especially when the number of samples are low. It is more advantageous to apply different methods simultaneously than using growth parameter alone in order to study for precise evaluation of the quality of fish growth performance. The methods are very practical for studying food utilization and growth quality of fish in different environmental conditions and with different behaviors in aquaculture as well as in natural ecosystem where food consumption rate and feeding regime cannot be under control. [source] BACTERIAL FORMATION OF HISTAMINE IN JACK MACKEREL (TRACHURUS SYMMETRICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2004A. BERMEJO ABSTRACT Peak histamine concentrations of 0.023, 0.031 and 0.027 g histamine/100 g muscle and maximal bacteria concentrations of 1.75, 1.59 and 0.423 g dry cells/100 g muscle were observed in muscles of jack mackerel stored at 25, 15 and 5C, respectively. Incubated fish homogenates suggest rate and transport limitations in histamine formation in muscle. The Mulchandani model predicted bacterial growth in muscle. The Luedeking and Piret expression fitted histamine formation in muscle; , values were 3.0 × 10,3, 1.23 × 10,2 and 4.17 × 10,2 g histamine/g dry cells, while ,-values were 4.5 × 104, 8.0 × 10,5 and 0 g histamine/g dry cells × h at 25, 15, and 5C, respectively. The model predicts that jack mackerel could be stored from 4.5 to 5.5 days in ice, from 1 to 2 days at 15C and from 17 h to 2 days at 25C before fishmeal quality might be affected. [source] GROWTH AND CHARACTERIZATION OF THE HISTAMINE-FORMING BACTERIA OF JACK MACKEREL (TRACHURUS SYMMETRICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2003ALINA BERMEJO ABSTRACT Consumption of fish with high histamine poses health hazards. The isolation, identification and viable counts of the histamine-forming bacteria from jack mackerel in batch cultures in trypticase soy broth with 2 % histidine at 25, 15 and 5C were performed. Proteus vulgaris, Aeromonas hydrophila and Photobacterium damsela were the most histamine producing population. The community had a maximal specific growth rate (,max) of 0.304, 0.217 and 0.048 h,1 at 25, 15 and 5C, respectively. Mulchandani's model, with an exponential value of 5.21, predicted bacterial growth. Histamine production was proportional to growth rate; proportionality coefficients were 1.987, 0.436 and 1.439 and the community's maximal spefic rates for histamine production were 0.604, 0.095 and 0.068 [g histamine (g dry cells h),1] af 25, 15 and SC, respectively. Lesser histamine production at 15C needs further investigation in whole fish, as it is a relevant result forfish handling. [source] Gel Strengthening Effect of Wood Extract on Surimi Produced from Mackerel Stored in IceJOURNAL OF FOOD SCIENCE, Issue 8 2009A.K. Balange ABSTRACT:, The effect of ethanolic kiam wood extract (EKWE) and commercial tannin (CT) on the gel properties of surimi produced from mackerel (Rastrelliger kanagurta) stored in ice for different times (0 to 12 d) was studied. During 12 d of iced storage, pH, total volatile base (TVB), trimethylamine (TMA), and trichloroacetic acid (TCA)-soluble peptide contents as well as thiobarbituric acid-reactive substances (TBARS) of mackerel mince increased while myosin heavy chain (MHC) band intensity decreased continuously (P,< 0.05). The result suggested that deterioration, protein degradation, and lipid oxidation proceeded with increasing storage time. For corresponding surimi, TVB and TMA were almost removed and TBARS and TCA soluble peptide contents were decreased. Conversely, MHC became more concentrated. Decreases in gel-forming ability of surimi were observed when fish used as raw material were stored in ice for a longer time, regardless of EKWE or CT addition. Whiteness of surimi gel decreased and expressible moisture increased especially when the storage time increased. However, superior breaking force and deformation of surimi gel with 0.15% EKWE or 0.30% CT added, compared to those of the control gel were observed during the first 6 d of the storage. Thereafter, EKWE and CT had no gel enhancing effect on surimi. Therefore, freshness was a crucial factor determining gel enhancing ability of EKWE or CT toward mackerel surimi. [source] Persistent Organic Pollutants in Fish Oil Supplements on the Canadian Market: Polychlorinated Biphenyls and Organochlorine InsecticidesJOURNAL OF FOOD SCIENCE, Issue 1 2009Dorothea F.K. Rawn ABSTRACT:, Fish and seal oil dietary supplements, marketed to be rich in omega-3 fatty acids, are frequently consumed by Canadians. Samples of these supplements (n,= 30) were collected in Vancouver, Canada, between 2005 and 2007. All oil supplements were analyzed for polychlorinated biphenyls (PCBs) and organochlorine insecticides (OCs) and each sample was found to contain detectable residues. The highest ,PCB and ,DDT (1,1,1-trichloro-di-(4-chlorophenyl)ethane) concentrations (10400 ng/g and 3310 ng/g, respectively) were found in a shark oil sample while lowest levels were found in supplements prepared using mixed fish oils (anchovy, mackerel, and sardine) (0.711 ng ,PCB/g and 0.189 ng ,DDT/g). Mean ,PCB concentrations in oil supplements were 34.5, 24.2, 25.1, 95.3, 12.0, 5260, 321, and 519 ng/g in unidentified fish, mixed fish containing no salmon, mixed fish with salmon, salmon, vegetable with mixed fish, shark, menhaden (n,= 1), and seal (n,= 1), respectively. Maximum concentrations of the other OCs were generally observed in the seal oil. The hexachlorinated PCB congeners were the dominant contributors to ,PCB levels, while ,DDT was the greatest contributor to organochlorine levels. Intake estimates were made using maximum dosages on manufacturers' labels and results varied widely due to the large difference in residue concentrations obtained. Average ,PCB and ,DDT intakes were calculated to be 736 ± 2840 ng/d and 304 ± 948 ng/d, respectively. [source] Effect of Combining Proteolysis and Lactic Acid Bacterial Fermentation on the Characteristics of Minced MackerelJOURNAL OF FOOD SCIENCE, Issue 3 2005Li-Jung Yin ABSTRACT: To improve the quality of fish muscle, mackerel muscle protein was hydrolyzed by proteases from Aspergillus oryzae, and then fermented by lactic acid bacteria (LAB). The highest protease activities were obtained from A. oryzae after 72 h incubation at 25°C. Acidic protease activity was much higher than neutral and alkaline proteases. SDS-PAGE indicated the degradation of muscle proteins after 1 or 2 h hydrolysis by A. oryzae proteases at 50°C. During 48 h fermentation by Pediococcus pentosaceus L and S at 37°C, rapid growth of LAB, decline in pH, and suppression in the growth of microflora, Enterobacteriaceae, Staphylococcus, and Pseudomonas, occurred while increases in whiteness, nonprotein nitrogen, sensory quality, and free amino acids were observed. These data suggested that the acceptability of LAB -fermented mackerel hydrolysates could be substantially improved. [source] The Physicochemical Quality Characteristics of Charcoal Grilled MackerelsJOURNAL OF FOOD SCIENCE, Issue 3 2002M-Y. Kim ABSTRACT: : The effects of different fuel sources used in grilling on the physicochemical and sensory characteristics of mackerel were investigated. Oak and sawdust charcoals were used as fuel sources. The content of saturated fatty acids was increased during grilling. Histidine was the most predominant amino acid; grilling significantly increased glutamic acid. Mackerel shows a high inosine 5,-monophosphate content that is increased during grilling. Oak charcoal and sawdust charcoal contained high levels of potassium and sodium, respectively. Potassium content was increased at the surface muscle of oak charcoal grilled mackerel (OM). The flavor preference for OM was significantly (p < 0.05%) higher than for sawdust charcoal grilled mackerel. These results indicate that physicochemical and sensory properties of grilled foods can be affected by the fuel source. [source] | |||||||||||||||||||