The species Oncorhynchus mykiss is characterized by a complex life history that presents a significant challenge for population monitoring and conservation management. Many factors contribute to genetic variation in O. mykiss populations, including sympatry among migratory phenotypes, habitat heterogeneity, hatchery introgression, and immigration (stray) rates. The relative influences of these ...

Microplastic (MP) sorption and transfer of chemical contaminants has been widely reported, yet few studies have investigated combined effects contaminant-loaded MPs on organisms. This study examined pristine or chlorpyrifos (CPF)-loaded polystyrene (PS)‎ fragments histopathological histomorphometrical biomarkers in rainbow trout (Onchorhynchus mykiss)‎. In laboratory, O. mykiss were exposed for...

Adult steelhead Oncorhynchus mykiss tagged with archival transmitters primarily migrated through a large river corridor at depths >2 m interspersed with frequent but short (<5 min) periods closer to the surface. The recorded swimming depths and behaviours probably provided adequate hydrostatic compensation for the supersaturated dissolved gas conditions encountered and probably limited developm...

A new, image-based, tritiated ligand technique for measuring cardiac β2 -adrenoceptor (β2 -AR) binding characteristics was developed and validated with adult rainbow trout Oncorhynchus mykiss hearts so that the tissue limitation of traditional receptor binding techniques could be overcome and measurements could be made in hearts nearly 14-times smaller than previously used. The myocardial cell-...

The profiles of specific fatty acids (FA) in white muscle and liver of fasting steelhead trout Oncorhynchus mykiss were evaluated at three periods during their prespawning migration and at kelt emigration in the Snake-Columbia River of Washington, Oregon and Idaho, to improve the understanding of energy change. Twenty-seven FAs were identified; depletion of 10 of these was positively correlated...

Adaptation to novel habitats and phenotypic plasticity can be counteracting forces in evolution, but both are key characteristics of the life history of steelhead/rainbow trout (Oncorhynchus mykiss). Anadromous steelhead reproduce in freshwater river systems and small coastal streams but grow and mature in the ocean. Resident rainbow trout, either sympatric with steelhead or isolated above barr...

The streams draining of into San Francisco Bay, California, have been impacted by habitat alteration for over 150 years, and roads, dams, water diversions, and other impediments now block the paths of many aquatic migratory species. These changes can affect the genetic structure of fish populations, as well as driving adaptive evolution to novel environmental conditions. Here, we determine the ...

Aloe vera has been used worldwide in pharmaceutical, food and cosmetic industries due to the plethora of biological activities of its constituents. This study was done to evaluate the effects of dietary aloe vera on growth and lipid peroxidation in rainbow trout (Oncorhynchus mykiss). A total number of 480 O. mykiss (mean weight 9.50 ± 0.85 g) were randomized into four experimental groups inclu...

We describe 12 diagnostic single nucleotide polymorphism (SNP) assays for use in species identification among rainbow and cutthroat trout: five of these loci have alleles unique to rainbow trout (Oncorhynchus mykiss), three unique to westslope cutthroat trout (O. clarkii lewisi) and four unique to Yellowstone cutthroat trout (O. clarkii bouvieri). These diagnostic assays were identified using a...

This study evaluated the effect of probiotics (Clostridium butyricum, Bacillus coagulans) and Chinese herb polysaccharides (Astragalus polysaccharides, APS) on growth performance, immunity, disease resistance, intestinal microbiota rainbow trout (Oncorhynchus mykiss). Specimens O. mykiss (n = 360; 79.9 ± 2.2 g) were fed for 42 days with different diets containing a basal diet (control, C0), sup...