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411.
412.
The most commercially important mollusk species from the Bulgarian Black Sea is the black mussel (Mytilus galloprovincialis). There is limited information about fat soluble vitamins, cholesterol, and fatty acid content of the Bulgarian Black Sea mussel. The aims of the present study are to determine and compare the fat soluble vitamin contents as well as relative daily intake of vitamins, cholesterol, fatty acid content, and lipid quality indices (atherogenic, thrombogenic) in the wild and farmed black mussels. Fat soluble vitamins and cholesterol were analyzed simultaneously using reverse phase high performance liquid chromatography. The fatty acid composition was analyzed by gas chromatography-mass spectrometry. In both mussels, fat soluble vitamins A and E were in high amounts, but they were a better source of vitamin D3. Cholesterol contents were 67.54 ± 0.50 mg/100 g ww (wild) and 49.88 ± 0.30 mg/100 g ww (farmed). The fatty acid distributions of wild and farmed mussels are: saturated > polyunsaturated > monounsaturated fatty acid. The n3/n6 and polyunsaturated/saturated fatty acid ratios were greater than that recommended by the Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO). A 100-g edible portion of both mussels contained from 0.252 g (wild) to 0.425 g (farmed) of eicosapentaenoic acid (EPA, C20:5n-3) + docosahexaenoic acid (DHA, 22:6n-3). 相似文献
413.
M D Jansen T Taksdal M A Wasmuth B Gjerset E Brun A B Olsen O Breck M Sandberg 《Journal of fish diseases》2010,33(5):391-402
A cohort study was initiated in the spring of 2006 to investigate epidemiological aspects and pathogenesis of salmonid alphavirus (SAV) subtype 3 infections and pancreas disease (PD). The aims were to assess involvement of the freshwater production phase, the extent and frequency of subclinical infections and to follow PD‐affected populations throughout the entire seawater production cycle, as well as investigate possible risk factors for PD outbreaks. Fish groups from 46 different Atlantic salmon freshwater sites in six counties were sampled once prior to seawater transfer and followed onto their seawater sites. A total of 51 Atlantic salmon seawater sites were included, and fish groups were sampled three times during the seawater production phase. SAV subtype 3 was not identified by real‐time RT‐PCR from samples collected in the freshwater phase, nor were any SAV‐neutralizing antibodies or histopathological changes consistent with PD. In the seawater phase, SAV was detected in samples from 23 of 36 (63.9%) studied sites located within the endemic region. No SAV subtype 3 was detected in samples from seawater sites located outside the endemic region. The cumulative incidence of PD during the production cycle amongst sites with SAV detected was 87% (20 of 23 sites). Average fish weight at time of PD diagnosis ranged from 461 to 5978 g, because of a wide variation in the timing of disease occurrence throughout the production cycle. Mortality levels following a PD diagnosis varied greatly between populations. The mean percentage mortality was 6.9% (±7.06) (range 0.7–26.9), while the mean duration of increased mortality following PD diagnosis was 2.8 months (±1.11) (range 1–6). 相似文献
414.
M D Jansen M A Wasmuth A B Olsen B Gjerset I Modahl O Breck R N Haldorsen R Hjelmeland T Taksdal 《Journal of fish diseases》2010,33(9):723-736
A prospective longitudinal study was performed on three cages at each of three Norwegian Atlantic salmon seawater sites that experienced outbreaks of pancreas disease (PD). Once salmonid alphavirus (SAV) ribonucleic acid (RNA) was detected by real‐time RT‐PCR (Rt RT‐PCR) at a site, it became detected in all studied cages and was persistently found until the end of the study period up to 19 months after first detection. SAV‐specific antibodies were detected at all sites until the end of the study period and were also found at a high prevalence in broodfish at the time of stripping. No evidence of increased viral activity was detected in these broodfish. One site tested negative over several months prior to the first detection of SAV by Rt RT‐PCR and SAV‐specific antibody, which occurred 1 month prior to clinical manifestations of PD. Moribund fish or thin fish/runts that were sampled after the first PD diagnosis had almost twice the risk of testing positive by one or more diagnostic tests compared to that of randomly selected apparently healthy individuals. This paper describes the first detailed investigation of the disease development of PD at site and cage level in Norway, as well as an assessment of the performance and agreement of the commonly used diagnostic tests. 相似文献