Search results for "Trout"

Type I keratin cDNAs from the rainbow trout: independent radiation of keratins in fish

2002

Five different type I keratins from a teleost fish, the rainbow trout Oncorhynchus mykiss, have been sequenced by cDNA cloning and identified at the protein level by peptide mass mapping using MALDI-MS. This showed that the entire range of type I keratins detected biochemically in this fish has now been sequenced. Three of the keratins are expressed in the epidermis (subtype Ie), whereas the other two occur in simple epithelia and mesenchymal cells (subtype Is). Among the Is keratins is an ortholog of human K18; the second Is polypeptide is clearly distinct from K18. We raised a new monoclonal antibody (F1F2, subclass IgG1) that specifically recognizes trout Is keratins, with negative react…

Dietary ontogeny and niche shift to piscivory in lacustrine brown trout Salmo trutta revealed by stomach content and stable isotope analyses

2012

The feeding ecology and ontogeny of a large size range of brown trout Salmo trutta in Lake Fyresvatnet, southern Norway, were examined by stomach content and stable isotope analyses. According to the stomach contents, the S. trutta changed their diet at c. 30 cm total length (L(T) ). The smaller size classes fed on benthic invertebrates and surface insects, whereas larger S. trutta (30 cm) fed mainly on whitefish Coregonus lavaretus. A similar, but more gradual shift to piscivory in the size range 25-30 cm was found when using the stable isotope mixing model SIAR to reveal dietary ontogeny. The δ¹³C isotopic signature confirmed that S. trutta independent of size predominantly relied upon be…

Different sensitivity of carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss) to the immunomodulatory effects of UVB irradiation.

2006

Abstract In order to study the sensitivity of two fish species, carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss), to the immunomodulatory effects of ultraviolet B (UVB) radiation, the fish were exposed to a single UVB dose of 50, 250, 500 or 1000 mJ cm−2. These species represent different phylogenetic groups of fish, and they differ also in their behaviour inhabitating often dark and turbid (carp) or clear and transparent waters (salmonids). Immune responses were studied on day 1 post-irradiation. Unexposed fish, and fish exposed to radiation depleted of UV wavelengths served as controls. UVB irradiation markedly enhanced the blood respiratory burst and cytotoxic activity in c…

Socializing makes thick-skinned individuals: on the density of epidermal alarm substance cells in cyprinid fish, the crucian carp (Carassius carassiu…

2010

Published version of an article in the journal: Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology. Also available on SpringerLink: http://dx.doi.org/10.1007/s00359-010-0550-4 In cyprinid fish, density of epidermal club cells (i.e. alarm substance cells) has been found to vary between lakes with different predator fauna. Because predators can be labelled with chemical cues from prey, we questioned if club cell density could be controlled indirectly by predators releasing prey cues. In particular, we suspected a possible feedback mechanism between chemical alarm signals and their cellular source. We raised crucian carp singly and in groups of four.…

Long-term UVB irradiation affects the immune functions of carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss).

2009

The effects of long-term, low-dose ultraviolet B (UVB) radiation on immune functions of two fish species representing different taxonomic groups, carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss), were assessed in this study. The fish were exposed to 7, 20 or 60 mJ cm(-2) UVB three times per week, for 6 weeks. In carp, UVB exposure affected the respiratory burst activity of blood and head kidney phagocytes, differential blood leukocyte counts and blood chemistry. Phytohemagglutinin (PHA)-stimulated in vitro proliferation responses of blood and head kidney lymphocytes, however, remained unchanged. Rainbow trout tolerated the irradiations with fewer alterations, but significant c…

Coping with continual danger: assessing alertness to visual disturbances in crucian carp following long-term exposure to chemical alarm signals.

2013

Chemical alarm signals in fish are passively released into the water from ruptured epidermal cells, and induce instant fright responses in conspecifics. Fish also display alarm responses to injured heterospecific skin, as well as to scent of piscivorous predators that have ingested prey. A conspicuous alertness to visual disturbances has also been observed in fish following long-term exposure to extracts of filtered, homogenized skin, but the chemical inducers of such vigilance are actually unknown. We tested if a continual exposure to water-soluble alarm signals, from either conspecifics or heterospecifics, affects alertness of fish. Based on previous experience, it was assumed that alertn…

The toxicity of MCPA to fish. Light and electron microscopy and the chemical analysis of the tissue.

1978

Metabolites of the aquatic pollutant diclofenac in fish bile.

2010

The uptake and metabolism of anti-inflammatory drug diclofenac (DCF) was studied by exposing rainbow trout (Oncorhynchus mykiss) to DCF intraperitoneally, and via water at concentration of 1.7 μg L(-1). The bile was collected and the formed metabolites were identified. The identification was based on the exact mass determinations by a time-of-flight mass analyzer and on the studies of fragments and fragmentation patterns of precursor ions by an ion trap mass analyzer. The main metabolites found were acyl glucuronides of hydroxylated DCFs. In addition, one ether glucuronide of hydroxylated DCF was found. Also, unmetabolized DCF was detected in the bile. The total bioconcentration factors (BC…

Wild brown trout affected by historical mining in the Cévennes national park, France.

2011

8 pages; International audience; In the protected area of the Cévennes National Park (Southern France), 114 wild brown trout (Salmo trutta fario) were captured at six locations affected to different extents by historical mining and metallurgy dating from the Iron Age to Modern Times. Cadmium and lead in trout livers and muscles reflect high sediment contamination, although an age-related effect was also detected for hepatic metal concentrations. Lead isotope signatures confirm exposure to drainage from mining and metallurgical waste. Developmental instability, assessed by fluctuating asymmetry, is significantly correlated with cadmium and lead concentrations in trout tissues, suggesting th…

Occurrence of Yersinia ruckeri infection in farmed whitefish, Coregonus peled Gmelin and Coregonus muksun Pallas, and Atlantic salmon, Salmo salar L.…

1986

Yersinia ruckeri, the aetiological agent of enteric redmouth disease (ERM), is now generally recognized to be distributed worldwide. The pathology and epizootiology of the disease was first described by Rucker (1966) and although rainbow trout, Salmo gairdneri Richardson, has been the most frequently affected species, all salmonids are now considered to be potential hosts for the organism (McDaniel 1979). The present paper reports the first confirmed occurrence of Y. ruckeri infection in farmed whitefish and Atlantic salmon, Salmo salar L., in Finland, with the known host range being extended to include the whitefish Coregonus peled Gmelin and Coregonus muksun Pallas . The outbreaks of infe…