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Atlantic Bluefin Tuna (atlantic + bluefin_tuna)
Selected AbstractsIdentification of Atlantic bluefin tuna (Thunnus thynnus) stocks from putative nurseries using otolith chemistryFISHERIES OCEANOGRAPHY, Issue 2 2003Jay R. Rooker Abstract Chemical signatures in the otoliths of teleost fishes represent natural tags that may reflect differences in the chemical and physical characteristics of an individuals' environment. Otolith chemistry of Atlantic bluefin tuna (Thunnus thynnus) was quantified to assess the feasibility of using these natural tags to discriminate juveniles (age 0 and age 1) from putative nurseries. A suite of six elements (Li, Mg, Ca, Mn, Sr and Ba) was measured in whole otoliths using solution-based inductively coupled plasma mass spectrometry. Otolith chemistry of age-1 T. thynnus collected from the two primary nurseries in the Mediterranean Sea and western Atlantic Ocean differed significantly, with a cross-validated classification accuracy of 85%. Spatial and temporal variation in otolith chemistry was evaluated for age-0 T. thynnus collected from three nurseries within the Mediterranean Sea: Alboran Sea (Spain), Ligurian Sea (northern Italy), and Tyrrhenian Sea (southern Italy). Distinct differences in otolith chemistry were detected among Mediterranean nurseries and classification accuracies ranged from 62 to 80%. Interannual trends in otolith chemistry were observed between year classes of age-0 T. thynnus in the Alboran Sea; however, no differences were detected between year classes in the Tyrrhenian Sea. Age-0 and age-1 T. thynnus collected from the same region (Ligurian Sea) were also compared and distinct differences in otolith chemistry were observed, indicating ontogenetic shifts in habitat or elemental discrimination. Findings suggest that otolith chemistry of juvenile T. thynnus from different nurseries are distinct and chemical signatures show some degree of temporal persistence, indicating the technique has considerable potential for use in future assessments of population connectivity and stock structure of T. thynnus. [source] Type and ultrastructure of Didymocystis wedli and Koellikerioides intestinalis (Digenea, Didymozoidae) cysts in captive Atlantic bluefin tuna (Thunnus thynnus Linnaeus, 1758)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2009I. Mladineo Summary Tissue encapsulation, one of the most common tissue reactions to invading parasites, is the hallmark sign of didymozoid (Digenea, Didymozoidae) infections in fish. Investigated were the types of intermediate filaments and ultrastructure of the connective tissue capsule elicited by the presence of didymozoids in the gills and intestine of Atlantic bluefin tuna (Thunnus thynnus Linnaeus, 1758). The evaluation was done performing TEM microscopy of two tissue-embedded didymozoid species, along with monoclonal antibodies labeling (anti-fish collagen type I, anti-human cytokeratin, anti-vimentin antibodies). Ultrastructure of Didymocystis wedli (Ariola, 1902) (prevalence = 61.75%, abundance = 28.91) encapsulated in gill filaments and Koellikerioides intestinalis (Yamaguti, 1970) (prevalence = 54.65%, abundance = 10.96) in the intestinal submucosa showed that the thin parasitic hindbody tegumentum was directly embedded in layers of connective tissue bands. Only a few cellular elements (lymphocytes, fibroblasts and fibrocytes) infiltrated the connective tissue capsule, which differed between the two didymozoid species in thickness, not in the type of filaments expressed. Cysts showed positive reaction to extracellular collagen as well as appearing positive for the cytoskeletal intermediate filaments vimentin and cytokeratin. [source] Pricing U.S. North Atlantic bluefin tuna and implications for managementAGRIBUSINESS : AN INTERNATIONAL JOURNAL, Issue 2 2001Michael T. Carroll Bluefin tuna is regarded as a high-quality product in the Japanese market and is characterized by an unusual marketing system by seafood industry standards. Each fish is individually inspected for various quality attributes before being flown to Japan for the fresh tuna market. The first objective of this study is to formally evaluate the degree to which the price of U.S. fresh bluefin tuna is determined by quality attributes of each fish, rather than by just the quantity supplied. This is accomplished using a Hedonic model. The results support the hypothesis that the fresh bluefin tuna price is, in fact, significantly influenced by the quality attributes of the fish, including the freshness, fat content, color, and shape. Interesting implications for public management of this highly valued resource arise from the results. [Econ-Lit citation: L150, L190, L660] © 2001 John Wiley & Sons, Inc. [source] A rapid latex agglutination test for gender identification in the Atlantic bluefin tuna, Thunnus thynnus (Linnaeus)AQUACULTURE RESEARCH, Issue 9 2010Elisabetta Micera Abstract A rapid, one-step agglutination assay has been developed, based on latex particles sensitized with antibodies against vitellogenin (Vtg), aimed at Atlantic bluefin tuna, Thunnus thynnus (Linnaeus) (ABFT), gender identification. The egg-yolk precursor protein Vtg was used as a gender marker for the assay as it is a female-specific protein synthesized during reproductive maturation. The presence of Vtg in the plasma was revealed in 60,120 s through an agglutination reaction by mixing small volumes of ABFT plasma and an anti-Vtg antibody-latex suspension on a microscope slide. The effectiveness of the present test was restricted to the months of May and June, concomitant with high circulating Vtg levels. Because of its rapidity and ease of performance in the field, the present gender identification assay could be useful for broodstock management in the aquaculture industry as well as in tagging studies on wild populations. [source] Growth, food intake and feed conversion rates in captive Atlantic bluefin tuna (Thunnus thynnus Linnaeus, 1758) under fattening conditionsAQUACULTURE RESEARCH, Issue 6 2005Felipe Aguado-Giménez First page of article [source] | ||||||||||