The objective of this study was to determine the impact of the Exxon Valdez oil spill on juvenile pink and chum salmon during their initial period of residency in nearshore marine habitats of western Prince William Sound. In oiled locations, both pink and chum salmon fry in the nearshore marine environment were contaminated by hydrocarbons in 1989, but not in 1990. Field observations and labora...

BACKGROUND Sea lice infection is the most expensive disease factor for Atlantic salmon sea-cage farming. For triploid salmon to be accepted as a commercial possibility, investigation of susceptibility of triploid salmon to sea lice infection is a fundamental milestone. The susceptibility of diploid and triploid salmon to infection with Lepeophtheirus salmonis was examined in a tank trial in Sco...

The role of escaped farmed salmon in spreading infectious agents from aquaculture to wild salmonid populations is largely unknown. This is a case study of potential disease interaction between escaped farmed and wild fish populations. In summer 2012, significant numbers of farmed Atlantic salmon were captured in the Hardangerfjord and in a local river. Genetic analyses of 59 of the escaped salm...

Relatively large rates of response to traits of economic importance have been observed in different selection experiments in salmon. Several QTL have been mapped in the salmon genome, explaining unprecedented levels of phenotypic variation. Owing to the relatively large selection intensity, individual loci may be indirectly selected, leaving molecular footprints of selection, together with incr...

Although species commonly modify habitats and thereby influence ecosystem structure and function, the factors governing the ecological importance of these modifications are not well understood. Pacific salmon have repeatedly been shown to positively influence the abundance of benthic biota by annually transferring large quantities of nutrients from marine systems to the nutrient-poor freshwater...

Predation on returning runs of adult salmon (Oncorhynchus spp.) can have a large influence on their spawning success. At McNeil River State Game Sanctuary (MRSGS), Alaska, brown bears (Ursus arctos) congregate in high numbers annually along the lower McNeil River to prey upon returning adult chum salmon (O. keta). Low chum salmon escapements into McNeil River since the late 1990s have been prop...

background : ligulae intestinalis is a parasitic cestode, which has the economic-health importance in fishery industries. the aim of this study was to determine the prevalence of this parasite in mazandaran. the effects of habitat temperature and kind of pool (sandy-cement) were considered as well. methods : in this study, 103 fish samples were obtained in all stages; the samples (male and fema...

Salmon migrate upstream against an opposing current in their natal river. However, the molecular mechanisms that stimulate upstream migratory behavior are poorly understood. Here, we show that 7α-hydroxypregnenolone (7α-OH PREG), a newly identified neuronal modulator of locomotion, acts as a key factor for upstream migration in salmon. We first identified 7α-OH PREG and cytochrome P450 7α-hydro...

Wild Atlantic salmon Salmo salar with swollen and/or bleeding vents (red vent syndrome) have been observed in rivers across England and Wales. Low numbers of salmon with this condition have previously been recorded, but reports have increased in 2006 and 2007. Affected and non-affected salmon were sampled from fish traps and their vent pathology was examined. Third stage larvae of the nematode ...

Analytical methods are needed to determine the presence of color additives in fish. We report a liquid chromatographic (LC) method developed to identify the synthetic form of the color additive astaxanthin in salmon, based on differences in the relative ratios of the configurational isomers of astaxanthin. The distributions of configurational isomers of astaxanthin in the flesh of wild Atlantic...