Adaptation of the brown trout to fresh water containing increasing concentrations of calcium resulted in a decrease in plasma electrolyte level and total electrolyte excretion. The electrolyte excretion rate was higher at the beginning than at the end of the urine collection periods. Hypophysectomized fish had a lower plasma electrolyte concentration than the controls. This deficiency was parti...

Empirical estimates of pathogen prevalence in samples of fish may underestimate true prevalence because available detection techniques are incapable of perfect detection. Trout of several species were collected from enzootic (Myxobolus cerebralis, causative agent in whirling disease) habitats, and individual fish were examined for presence of the parasite two or six times by one of four methods...

Salmonid fishes, native to the northern hemisphere, have become naturalized in many austral countries and appear linked to the decline of native fishes, particularly galaxiids. However, a lack of baseline information and the potential for confounding anthropogenic stressors have led to uncertainty regarding the association between salmonid invasions and galaxiid declines, especially in lakes, a...

We studied the uptake of L-serine by trout red blood cells and the effect of a /5-adrenergic agonist (isoproterenol) on this process. The results obtained indicate that L-serine is taken up by these cells by means of a concentrative process. The uptake seems to be mediated both by a sodium-dependent process and by a sodium-independent process. The sodium-dependent uptake is mediated by a transp...

Fifteen classical linkage groups were identified in two salmonid species (Salmo trutta and Salmo gairdneri) and three fertile, interspecific hybrids (S. gairdneri X Salmo clarki, Salvelinus fontinalis X Salvelinus namaycush and S. fontinalis X Salvelinus alpinus) by backcrossing multiply heterozygous individuals. These linkage relationships of electrophoretically detected, protein coding loci w...

Males are the heterogametic sex in salmonid fishes. In brown trout (Salmo trutta) the sex-determining locus, SEX, has been mapped to the end of linkage group BT-28, which corresponds to linkage group AS-8 and chromosome SSA15 in Atlantic salmon (Salmo salar). We set out to identify the sex chromosomes in brown trout. We isolated Atlantic salmon BAC clones containing microsatellite markers that ...

The mechanisms that can contribute in the fish movement strategies and the associated behaviour can be complex and related to the physiology, genetic and ecology of each species. In the case of the brown trout (Salmo trutta), in recent research works, individual differences in mobility have been observed in a population living in a high mountain river reach (Pyrenees, NE Spain). The population ...

The study was aimed at analysing body size in relation to form of gonad maturation (amount of mature germ cells) in 329 under-yearling sea trout males. The fish, aged 7 months, were caught in late October-early November in 3 streams located in north-western Poland. Each stream supported fish belonging to a different sib group. Standard histological techniques and a computer image analysis progr...

In the present report, an efficient method for isolating multiple cytosolic forms of glutathione S-transferases from liver and kidney cytosolic samples of two salmonid species (brown trout and Atlantic salmon) is described, and some of the multiple properties of these enzymes are presented. Glutathione S-transferases were partially purified by low-pressure affinity chromatography on a column wi...

1 Gesna Estudis Ambientals, S.L., Linyola, Catalonia, Spain 2 Institute of Aquatic Ecology, University of Girona, Girona, Catalonia, Spain 3 Department of Aninal Biology, University of Barcelona, Barcelona, Catalonia, Spain 4 Dirección de Medio Ambiente y Cambio Climático de España y Portugal, Endesa, Spain 5 Departamento de Medio Ambiente y Ciencias del Suelo, Universitat de Lleida, Lleida, Ca...