plasmacytoid leukemia of chinook salmon.plasmacytoid leukemia is a common disease of seawater pen-reared chinook salmon (oncorhynchus tshawytscha) in british columbia, canada, but has also been detected in wild salmon, in freshwater-reared salmon in united states, and in salmon from netpens in chile. the disease can be transmitted under laboratory conditions, and is associated with a retrovirus, the salmon leukemia virus. however, the proliferating plasmablasts are often infected with the microsporean enterocytozoon salmonis, which ma ...19979209333
a survey of microparasites present in adult migrating chinook salmon (oncorhynchus tshawytscha) in south-western british columbia determined by high-throughput quantitative polymerase chain reaction.microparasites play an important role in the demography, ecology and evolution of pacific salmonids. as salmon stocks continue to decline and the impacts of global climate change on fish populations become apparent, a greater understanding of microparasites in wild salmon populations is warranted. we used high-throughput, quantitative pcr (ht-qrt-pcr) to rapidly screen 82 adult chinook salmon from five geographically or genetically distinct groups (mostly returning to tributaries of the fraser r ...201728188649
gene expression profiling and environmental contaminant assessment of migrating pacific salmon in the fraser river watershed of british columbia.the health and physiological condition of anadromous salmon is of concern as their upriver migration requires navigation of human-impacted waterways and metabolism of stored energy reserves containing anthropogenic contaminants. such factors may affect reproductive success of fish stocks. this study investigates chemical contaminant burdens and select gene expression profiles in pacific sockeye (oncorhynchus nerka) and chinook (oncorhynchus tshawytscha) salmon which traverse the fraser river wat ...201019811841
an immune-complex glomerulonephritis of chinook salmon, oncorhynchus tshawytscha (walbaum).chinook salmon from new zealand were shown to have a generalized membranous glomerulonephritis that was most severe in large fish. marked thickening of the glomerular basement membrane was the most consistent lesion, with the presence of an electron-dense deposit beneath the capillary endothelium.severely affected glomeruli also had expansion of the mesangium and loss of capillaries,synechiae of the visceral and parietal epithelium and mild fibrosis of bowmans capsule. chinook salmon from britis ...200818752546
flesh quality of market-size farmed and wild british columbia salmon.this study compared the flesh quality of farmed and wild sources of british columbia (bc) salmon with respect to concentrations of polychlorinated biphenyl compounds, polychlorinated dibenzodioxins/dibenzofurans and their associated toxic equivalents, total mercury (thg), methylmercury (mehg), and selected fatty acids of known importance for human health viz., omega-3 (n-3) highly unsaturated fatty acids (n-3 hufas) and (n-6) fatty acids. skinned fillets from known sources of farmed atlantic, co ...200717310704
distribution, prevalence and severity of parvicapsula minibicornis infections among anadromous salmonids in the fraser river, british columbia, canada.polymerase chain reaction (pcr) and microscopic examination of stained kidney sections were used to diagnose infections with the myxozoan parasite parvicapsula minibicornis in maturing fraser river salmon. in 2 series of collections, the parasite was detected in 109 of 406 migrating sockeye salmon oncorhynchus nerka belonging to early stuart, early summer and summer run-timing groups, mainly upper fraser river stocks. however, the parasite was detected neither in fish at sea nor once they had mi ...200312718470
detection of infection and susceptibility of different pacific salmon stocks (oncorhynchus spp.) to the haemoflagellate cryptobia salmositica.the haematocrit centrifugation technique, modified by keeping the haematocrit tubes cold (between 1 and 10 c), was sensitive for detecting light infections of cryptobia salmositica (as few as 75 flagellates per ml of blood). in wet mount preparations, infections lighter than 7.5 x 10(3) flagellates per ml of blood could not be detected consistently. different pacific salmon stocks from british columbia demonstrated differences in susceptibility to c. salmositica in experimental studies using lab ...19846470889
sea lice, lepeophtheirus salmonis, transfer between wild sympatric adult and juvenile salmon on the north coast of british columbia, canada.we examine sea lice, lepeophtheirus salmonis, on juvenile and adult salmon from the north coast of british columbia between 2004 and 2006 in an area that does not at present contain salmon farms. there is a pronounced zonation in the abundance of l. salmonis on juvenile pink salmon, oncorhynchus gorbuscha, in the skeena and nass estuaries. abundances in the proximal and distal zones of these estuaries are 0.01 and 0.05 respectively. the outer zones serve as feeding and staging areas for the pink ...200919245630
molecular epidemiology of viral haemorrhagic septicaemia virus (vhsv) in british columbia, canada, reveals transmission from wild to farmed fish.viral haemorrhagic septicaemia virus (vhsv) is a fish pathogen found throughout the northern hemisphere and is capable of infecting and causing mortality in numerous marine and freshwater hosts. in the coastal waters of british columbia, canada, the virus has been detected for 20 yr with many occurrences of mass mortalities among populations of pacific herring clupea pallasii (valenciennes) and sardine sardinops sagax as well as detections among cultured atlantic salmo salar and chinook oncorhyn ...201323709462
piscine reovirus, but not jaundice syndrome, was transmissible to chinook salmon, oncorhynchus tshawytscha (walbaum), sockeye salmon, oncorhynchus nerka (walbaum), and atlantic salmon, salmo salar l.a jaundice syndrome occurs sporadically among sea-pen-farmed chinook salmon in british columbia, the westernmost province of canada. affected salmon are easily identified by a distinctive yellow discolouration of the abdominal and periorbital regions. through traditional diagnostics, no bacterial or viral agents were cultured from tissues of jaundiced chinook salmon; however, piscine reovirus (prv) was identified via rt-rpcr in all 10 affected fish sampled. by histopathology, jaundice syndrome i ...201625630226
mercury and other trace elements in farmed and wild salmon from british columbia, canada.the present study reports measured levels of hg and other trace elements in commercial salmon feed; farmed atlantic, coho, and chinook salmon (n = 110); and wild coho, chinook, chum, sockeye, and pink salmon (n = 91). metal concentrations in farmed and wild salmon from british columbia, canada, were relatively low and below human health consumption guidelines. methylmercury in all salmon samples (range, 0.03-0.1 microg/g wet wt) were below the 0.5 microg/g guideline set by health canada. negligi ...200818211126
a retrovirus in chinook salmon (oncorhynchus tshawytscha) with plasmacytoid leukemia and evidence for the etiology of the disease.a plasmacytoid leukemia (pl) has caused mortalities in chinook salmon (oncorhynchus tshawytscha) reared in seawater netpens in western british columbia, canada, since 1988. kidney or eye tissues from 11 of 13 fish from netpens with clinical pl had reverse transcriptase (rt) activity. this rt activity was associated with virus particles of retrovirus morphology and buoyant density. in a transmission experiment, pl-positive donor fish tissues also had rt activity and virus particles of retrovirus ...19921384964
quantitative interlake comparison of thyroid pathology in great lakes coho (oncorhynchus kisutch) and chinook (oncorhynchus tschawytscha) salmon.coho salmon (oncorhynchus kisutch) and chinook salmon (oncorhynchus tshawytscha) from lakes ontario, michigan, erie, or huron were found to suffer epizootics of thyroid hyperplasia and goiters which appeared to have an environmental etiology. there were 13-fold differences in goiter prevalence within the great lakes, and the differences in goiter frequency were correlated with the degree of thyroid hyperplasia. a means of assessing the degree of thyroid hyperplasia (thyroid index) is described, ...19817237420
distinguishing the impacts of inadequate prey and vessel traffic on an endangered killer whale (orcinus orca) population.managing endangered species often involves evaluating the relative impacts of multiple anthropogenic and ecological pressures. this challenge is particularly formidable for cetaceans, which spend the majority of their time underwater. noninvasive physiological approaches can be especially informative in this regard. we used a combination of fecal thyroid (t3) and glucocorticoid (gc) hormone measures to assess two threats influencing the endangered southern resident killer whales (srkw; orcinus o ...201222701560
habitat-based pcb environmental quality criteria for the protection of endangered killer whales (orcinus orca).the development of an area-based polychlorinated biphenyl (pcb) food-web bioaccumulation model enabled a critical evaluation of the efficacy of sediment quality criteria and prey tissue residue guidelines in protecting fish-eating resident killer whales of british columbia and adjacent waters. model-predicted and observed pcb concentrations in resident killer whales and chinook salmon were in good agreement, supporting the model's application for risk assessment and criteria development. model a ...201223098163
persistent organic pollutants in chinook salmon (oncorhynchus tshawytscha): implications for resident killer whales of british columbia and adjacent waters.we measured persistent organic pollutant (pop) concentrations in chinook salmon (oncorhynchus tshawytscha) in order to characterize dietary exposure in the highly contaminated, salmon-eating northeastern pacific resident killer whales. we estimate that 97 to 99% of polychlorinated biphenyls (pcbs), polychlorinated dibenzo-p-dioxins (pcdds), polychlorinated dibenzofurans (pcdfs), dichlorodiphenyltrichloroethane (ddt), and hexachlorocyclohexane (hch) in returning adult chinook were acquired during ...200918702563
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