Residues of PBDEs in northeastern Pacific marine fish: evidence for spatial and temporal trends.

In the flesh (skinless fillet) of chinook, chum, coho, pink, and sockeye salmon (Oncorhynchus tshawytscha, O. keta, O. kisutch, O.

Development and validation of protocols to differentiate PCB patterns between farmed and wild salmon.

Polychlorinated biphenyl (PCB) congener patterns based on full congener PCB analyses of three farmed and five wild species of salmon from coastal British Columbia, Canada are compared using principal components analysis (PCA) and the best fit linear decomposition of the observed PCB composition in terms of Aroclor 1242, 1254, and 1260 end-members. The two complementary analysis methods are used to investigate congener composition pattern differences between species, trophic levels, feeding preferences, and farmed or wild feeding regimes, with the intent of better understanding PCB processes in both salmon and salmon consumers. PCA supports classification of PCB congeners into nine groups based on a) structure activity groups (SAG) related to the bioaccumulation potential in fish-eating mammals, b) Cl number, and c) the numbers of vicinal meta- and para-H.

Dietary lipid composition affects the gene expression of gill Na(+)/K (+)-ATPase alpha1b but not the alpha1a isoform in juvenile fall chinook salmon (Oncorhynchus tshawytscha).

We assessed the effects of dietary fatty acid composition on sodium-potassium ATPase (Na(+)/K(+)-ATPase) activity and isoform expression in the gills of juvenile fall chinook salmon, Oncorhynchus tshawytscha by supplementing diets with either anchovy oil (AO) or AO blended with canola oil (CO) so that CO comprised 0% (0CO), 11% (11CO), 22% (22CO), 33% (33CO), 43% (43CO), or 54% (54CO) of the measured dietary lipid content. The effects of diet were assessed in freshwater (FW) following 104 days of diet manipulation, in response to 24-h seawater (SW) transfer at this time, and following an additional 35 days of SW acclimation. Gill Na(+)/K(+)-ATPase activity was not significantly affected by diet at any sampling time, and there were no consistent effects of diet on the expression of the Na(+)/K(+)-ATPase alpha1a isoform.

Use of terrestrial based lipids in aquaculture feeds and the effects on flesh organohalogen and fatty acid concentrations in farmed Atlantic salmon.

Consumption of salmon, wild or farmed, has been encouraged by many scientists and by national and international health organizations due to the potential health benefits associated with their high contents of omega-3 (n-3) highly unsaturated fatty acids (n-3 HUFAs). In 2004, there was increased public concern regarding the safety of farmed Atlantic salmon following the publication of several studies that indicated higher levels of organohalogens in their flesh relative to those noted in the flesh of wild Pacific salmon. Farmed salmon obtain most of these contaminants from the consumption of marine fish oil (MFO) present in salmon feed.

Influence of diet and ration level on benzo[a]pyrene metabolism and excretion in rainbow trout (Oncorhynchus mykiss).

Juvenile rainbow trout (Oncorhynchus mykiss) were fasted or fed one of three isoenergetic diets varying in protein and lipid content at full satiation levels or half rations for up to 9 weeks. At 3, 6, and 9 weeks, fish in each treatment group were dosed intraperitoneally with 10 mg tritiated benzo[a]pyrene [3H]-B[a]P/kg (B[a]P) to examine the effects of diet composition and energy intake on xenobiotic biotransformation and excretion. The percent dose eliminated during the experiment did not differ among fish receiving the different diet compositions or rations (range 73% to 84%).

The effects of diet composition and ration on biotransformation enzymes and stress parameters in rainbow trout, Oncorhynchus mykiss.

Juvenile rainbow trout (Oncorhynchus mykiss) were fed one of three isoenergetic diets varying in protein (35-55%) and lipid content (8-18%), at full satiation levels or half rations for 6 weeks in order to investigate the effects of diet on baseline stress parameters and biotransformation enzyme activity. Growth was greatest in fish fed to satiation on a low protein and high lipid diet. Stress parameters, including plasma lactate, glucose and cortisol concentrations were not significantly affected by dietary treatment or ration.

Copper metabolism in actively growing rainbow trout (Oncorhynchus mykiss): interactions between dietary and waterborne copper uptake.

Juvenile rainbow trout Oncorhynchus mykiss were exposed to diets with low (12.6 nmol g(-1)), normal (50.4 nmol g(-1)) or elevated (4437.