The highlighted article in this issue by Tilton et al. (2005a) is an innovative approach to evaluate the modulation of estrogen receptor (ER) and aryl hydrocarbon (Ah)-receptor pathways as mechanisms underlying indole-3-carbinol (I3C) tumor promotion in rainbow trout (Onchorhynchus mykiss). I3C and its major in vivo component 3,3'-diindolylmethane (DIM) are potent tumor promoters that appear to...

Rainbow trout are carnivorous fish and poor metabolizers of carbohydrates, which established this species as a model organism to study the comparative physiology of insulin. Following the recent characterisation of key roles of several miRNAs in the insulin action on hepatic intermediary metabolism in mammalian models, we investigated the hypothesis that hepatic miRNA expression is postprandial...

Gut-associated lymphocytes were described in fish, but their involvement in immune responses is still unknown. In rainbow trout, intraepithelial lymphocytes (IELs) are scattered between gut epithelial cells, but neither Peyer's patches nor mesenteric lymph nodes were identified. Rainbow trout IELs contain mainly T cells, because they expressed transcripts of T cell marker homologs of CD8, CD4, ...

Objective- The study aims to determine efficacy of propofol as an inmersión agent to induce anesthesia in rainbow trout (Oncorhynchus mykiss). Design- Experimental study. Animals- 36 healthy rainbow trout Procedure- Trouts were sorted ramdomly in two groups, 18 fish each one. Both groups were anesthesized by bath, one of them with 2,5 mg/l, the other one at 5 mg/l concentratio...

When nonnative species become established within new communities, competition may play a role in determining the persistence of ecologically similar native species. In western North America, many native cutthroat trout (Oncorhynchus clarkii) populations have been replaced by nonnative rainbow trout (Oncorhynchus mykiss). Superior competitive ability of rainbow trout and cutthroat–rainbow trout ...

Myxobolus cerebralis caused severe declines in rainbow trout populations across Colorado following its introduction in the 1980s. One promising approach for the recovery of Colorado's rainbow trout populations has been the production of rainbow trout that are genetically resistant to the parasite. We introduced one of these resistant crosses, known as the GR×CRR (cross between the German Rainbo...

Polymorphism. A variable number of tandem repeat (VNTR; Nakamura et al., 1987) polymorphism was detected in rainbow trout (Oncorhynchus rnykiss Walbaum) using BgZII. The probe, RW9401, was isolated from a genomic DNA cosmid library developed from the RTG-2 cell line (Wolf and Quimby, 1962). Method of Detection. Nylon filters containing rainbow trout genomic DNA digested with BgZII were prehy...

Olfactory epithelial structure and olfactory bulb neurophysiological responses were measured in chinook salmon and rainbow trout in response to 25 to 300 mg copper (Cu)/L. Using confocal laser scanning microscopy, the number of olfactory receptors was significantly reduced in chinook salmon exposed to $50 mg Cu/L and in rainbow trout exposed to $200 mg Cu/L for 1 h. The number of receptors was ...

Freshwater fish populations often exist in systems characterized by novel ecological processes resulting from human alteration. Salmonid embedded within coldwater sections of warmwater rivers are spatially constrained habitat availability. Tailwater contend with fluctuating river discharges and density-dependent associated stocking exploitation. sustained through versus natural reproduction may...

As there are few data on primary structures of fish apolipoproteins (apo), we determined the N-terminal sequence of a 28 kDa major serum protein of rainbow trout, a possible homologue of apoAI protein in higher vertebrates. Rainbow trout serum was separated by two-dimensional electrophoresis. A spot of the 28 kDa protein (pl 5.45) was cut out and directly applied to a protein sequencer. We succ...