Aquaculture and Fisheries最新文献

Targeted metabolomic analysis was conducted on juvenile Chinook salmon exposed for 10 days to wastewater effluent (WWE) from a large urban treatment plant. Exposures included five dilutions of WWE (20%, 5.3%, 1.4%, 0.4%, and 0.1%) and a control with 7 replicates per treatment. Liver was extracted from fish and analyzed via liquid chromatography – mass spectrometry (LC-MS) for 361 endogenous metabolites, of which 185 were detected. Control-versus-treatment comparisons identified several metabolites that were associated with altered biochemical pathways observed for all treatments, including several that are important for energy generation and utilization. These altered pathways are crucial for fish health and may be an early indicator of potential adverse effects on growth, reproduction, behavior, and immune function. Juvenile ocean-type Chinook salmon spend several days to weeks in the nearshore estuary where they may encounter high concentrations of WWE contaminants. They are exposed to a wide range of potent pharmaceuticals, personal care products, and industrial compounds from WWE that have the potential to affect physiological homeostasis and disrupt their normal life cycle.

Crucian carp (Carassius auratus gibelio), an extensively cultivated freshwater fish, was one of the model species for the study of fish immunology. Polyclonal antibodies were advantageous molecular tools for studying teleost immune system. Specifically, polyclonal antibodies reacting with immunoglobulins (Ig) were used successfully in studies of the teleost fishes. In the present study, we produced polyclonal antibody against CH2 domains of crucian carp IgM, and measured the in vivo dynamics of IgM mRNA caused by CyHV-2 infection. The recombinant protein IgM with relative molecular weight about 53 KD was correctly expressed in prokaryotic cells. The specificity of the polyclonal antibody was evaluated by Western blotting and results revealed that the antibody not only specifically recognized crucian carp serum but also cross-reacted with grass carp serum. Quantitative RT-PCR analysis demonstrated the expression of IgM mRNA changed significantly after CyHV-2 infection. The expression of IgM in the kidney increased and reached a maximum at 6 h post-infection (hpi), while dropped to a low level at 5 days post-infection (dpi). In conclusion, the expression of IgM was significantly upregulated in the kidney of crucian carp infected with CyHV-2, indicating that IgM played a potential role in systemic immunity against viral infection. Polyclonal antibody against crucian carp IgM had certain clinical relevance, which might provide insight into the early stage of virus infection and prevention of the disease.

Good information is the basis for good decisions. For many invaluable salmon species, chemical information is necessary to guide and fine-tune their migrations to and from freshwater mating grounds. A problem is that salmon of the current world are running a gauntlet of toxic chemicals arising from diverse anthropogenic inputs and these chemicals are known to disrupt information. There is sufficient evidence that effluents from cities, mines, agriculture and industry contain chemicals that can rapidly, and sometimes irreversibly, impair the olfactory sense that salmon use to gather information. Some toxic inputs may not only be strong enough to impair migration, but be strong enough to redirect salmon away from their routes. There is also evidence that some synthetic chemicals may serve as the basis for ‘new’ information and be useful in making correct migratory decisions. On the plus side, there are examples of new regulations that limit the input of chemicals of known olfactory toxicity, but on the minus side, increased urbanization and global climate change will likely increase the number and/or severity of some neurotoxic inputs. Here we identify the specific avenues of chemical risks to information disruption and in so doing prioritize and rank the risks to migrating salmon. The data collected here can be used to lay the foundation for modelling the effects of anthropogenic inputs on information disruption in diverse salmonid species from around the world and therefore help secure their longevity in a changing chemical environment.