Zinc Influx Across the Isolated, Perfused Head Preparation of the Rainbow Trout (Salmo gairdneri) in Hard and Soft Water

1988 ◽  
Vol 45 (12) ◽  
pp. 2206-2215 ◽  
Author(s):  
Douglas J. Spry ◽  
Chris M. Wood
Keyword(s):  
Steady State ◽  
Rainbow Trout ◽  
Hard Water ◽  
Soft Water ◽  
Chloride Cells ◽  
Salmo Gairdneri ◽  
First Order ◽  
Scanning Electron Micrography ◽  
Primary Substrate ◽  
Stimulation Of

At a waterborne [Zn] of 1.9 mg∙L−1 in hard water (~1 mmol Ca∙L−1), Zn influx across an isolated, saline-perfused head preparation of rainbow trout (Salmo gairdneri) was about 1.5 nmol∙kg−1∙h−1 through the lamellar pathway and about 1 nmol∙kg−1∙h−1 through the filamental route. Flux rates came rapidly to steady state in both pathways. Trout preexposed to artificial soft water (~0.05 mmol Ca∙L−1) for 5 d showed differential stimulation of flux rates to about 42 and 5 nmol Zn∙kg−1∙h−1 through the lamellar and filamental pathways, respectively. Under these conditions, steady-state fluxes across the lamellae did not occur until 15–20 min after the start of perfusion. Preparations from hardwater-acclimated trout tested in soft water gave typical hardwater fluxes showing that these changes in influx were not simply due to acute exposure of the gill surface to low waterborne [Ca]. Influxes in softwater trout, studied over [Zn] from 0.4 to 7.5 mg Zn∙L−1, revealed a saturable, first-order uptake with apparent Jmax and Km of 150 nequiv∙kg−1∙h−1 and 1.5 mg Zn∙L−1 (23 μmol∙L−1), respectively. Because the apparent Km is in the toxic range, Zn is clearly not the primary substrate. Scanning electron micrography revealed hypertrophy and increased apical exposure of chloride cells; this stimulation, coupled with the increase in Zn influx, suggests that chloride cells may be the site of entry of Zn across the gill.

The Influence of Calcium on the Physiological Responses of the Rainbow Trout, Salmo Gairdneri, to Low Environmental pH

1980 ◽  
Vol 88 (1) ◽  
pp. 109-132
Author(s):  
D. G. McDONALD ◽  
H. HŌBE ◽  
C. M. WOOD
Keyword(s):  
Rainbow Trout ◽  
Calcium Concentration ◽  
Physiological Responses ◽  
Hard Water ◽  
Low Ph ◽  
Soft Water ◽  
Salmo Gairdneri ◽  
Minor Depression ◽  
Regulatory Failure ◽  
A Minor

The physiological responses of 1- to 2-year-old rainbow trout to low pH are dependent on the environmental calcium concentration. Trout, maintained for 5 days in moderately hard water ([Ca2+] = 1·6–2·7 m-equiv/1) at a mean pH of 4·3, developed a major blood acidosis but exhibited only a minor depression in plasma ion levels. In acidified soft water ([Ca2+] = 0·3 m-equiv/1), only a minor acidosis occurred, but plasma ion levels fell and there were substantially greater mortalities. Lethal bioassays performed on fingerling trout over a range of pH levels (3·0–4·8) revealed an important influence of external [Ca2+] on resistance to acid exposure. Terminal physiological measurements on adult fish succumbing to low pH in soft water indicate the singular importance of iono-regulatory failure as the toxic mechanism of action under these circumstances.

Water Quality Modifies Uptake of Waterborne Methylmercury by Rainbow Trout, Salmo gairdneri

1983 ◽  
Vol 40 (6) ◽  
pp. 824-828 ◽  
Author(s):  
D. W. Rodgers ◽  
F. W. H. Beamish
Keyword(s):  
Water Quality ◽  
Rainbow Trout ◽  
Mercuric Chloride ◽  
Relative Efficiency ◽  
Zinc Sulphate ◽  
Hard Water ◽  
Soft Water ◽  
Salmo Gairdneri ◽  
Calcium Dependent ◽  
Sublethal Concentrations

We measured the efficiency of uptake of waterborne methylmercury relative to oxygen consumption for rainbow trout, Salmo gairdneri, in hard or soft water and during exposure to sublethal concentrations of mercuric chloride or zinc sulphate. The relative efficiency of methylmercury uptake in soft water was more than double that measured in hard water. When mercuric chloride was added with waterborne methylmercury, uptake efficiency was further increased, with similar values obtained in hard and soft water. In contrast, addition of zinc sulphate decreased the relative efficiency of methylmercury uptake. Water quality thus significantly affects the accumulation of waterborne methylmercury by fish. In particular, calcium-dependent changes in gill permeability may explain elevated methylmercury residues observed in fish from lakes of low alkalinity and pH.

Rapid Branchial Excretion of Dietary Quinoline by Rainbow Trout (Salmo gairdneri)

1989 ◽  
Vol 46 (4) ◽  
pp. 705-713 ◽  
Author(s):  
D. D. Dauble ◽  
L. R. Curtis
Keyword(s):  
Rainbow Trout ◽  
Parent Compound ◽  
Serum Levels ◽  
Nitrogen Heterocycle ◽  
Fecal Excretion ◽  
Salmo Gairdneri ◽  
First Order ◽  
Body Model ◽  
Β Phase ◽  
Gut Epithelium

Excretion of the nitrogen heterocycle 14C-quinoline was characterized in rainbow trout (Salmo gairdneri) following its ingestion with food. Quinoline-derived radioactivity was readily absorbed from the stomach as shown by peak serum levels that occurred 4–8 h after feeding. Pharmacokinetics were described using a two-compartment body model with first-order absorption and disposition; estimated half-lives for the α and β phase were 4.1 and 54.1 h, respectively. About 98% of the ingested dose was absorbed by gut epithelium before fecal excretion. Depending on dose, 71–83% of the ingested radioactivity was excreted during the first 24 h after feeding. Branchial elimination was the primary route of excretion since all other routes (fecal, biliary, urinary, and dermal) contributed < 5% of the eliminated dose within 48 h after ingestion. There was evidence for saturation of minor excretory pathways as the dose was increased from 1 to 100 mg quinoline∙kg−1 body weight. Apparent spillover occurred into the branchial route at the 100 mg∙kg−1 dose. Dietary quinoline was eliminated across the gills as parent compound, independent of the dose.

scholarly journals Present and potential nitrogen outputs from Norwegian soft water lakes – an assessment made by applying the steady-state First-order Acidity Balance (FAB) model

2002 ◽  
Vol 6 (1) ◽  
pp. 101-112 ◽  
Author(s):  
Ø. Kaste ◽  
A. Henriksen ◽  
M. Posch
Keyword(s):  
Steady State ◽  
Critical Loads ◽  
N Deposition ◽  
Soft Water ◽  
N Leaching ◽  
First Order ◽  
Fab Model ◽  
The Future ◽  
N Immobilisation

Abstract. The steady-state First-order Acidity Balance (FAB) model for calculating critical loads of sulphur (S) and nitrogen (N) is applied to 609 Norwegian soft-water lakes to assess the future nitrate (NO3‾) leaching potential under present (1992-96) S and N deposition. The lakes were separated into five groups receiving increasing levels of N deposition (<25, 25-49, 50-74, 75-99 and 100-125 meq m-2yr-1). Using long-term sustainable N sink rates presently recommended for FAB model applications, N immobilisation, net N uptake in forests, denitrification and in-lake N retention were estimated for each group of lakes. Altogether, the long-term N sinks constituted 9.9 ± 3.2 to 40.5 ± 11.4 meq m-2yr-1 in the lowest and highest N deposition categories, respectively. At most sites, the current N deposition exceeds the amount of N retained by long-term sustainable N sinks plus the NO3‾ loss via the lake outlets. This excess N, which is currently retained within the catchments may, according to the FAB model, leach as acidifying NO3‾ in the future. If these predictions are fulfilled, NO3‾ leaching at sites in the various N deposition categories will increase dramatically from present (1995) mean levels of 1-20 meq m-2yr-1, to mean levels of 7-70 meq m-2yr-1 at future steady state. To illustrate the significance of such an increase in NO3‾ leaching, the mean Acid Neutralising Capacity (ANC) at sites in the highest N deposition category may decrease from -18 ± 15 μeq L-1 at present, to -40 ± 20 μeq L-1. Under present S and N deposition levels, the FAB model predicts that 46% of the Norwegian lakes may experience exceedances of critical loads for acidifying deposition. In comparison, the Steady-State Water Chemistry model (SSWC), which considers only the present N leaching level, estimates critical load exceedances in 37% of the lakes under the same deposition level. Thus far, there are great uncertainties regarding both the time scales and the extent of future N leaching, and it is largely unknown whether the FAB model predictions will ever be fulfilled. Hence, long-term monitoring and further studies on N immobilisation processes under varying N deposition levels and ecosystem types seem necessary to make better predictions of future NO3‾ leaching. Keywords: Lakes, hydrochemistry, nitrogen, nitrate, sinks, leaching, acidification, critical loads, FAB model

Physiological disturbances in rainbow trout (Salmo gairdneri) during acid and aluminum exposures in soft water of two calcium concentrations

1989 ◽  
Vol 67 (2) ◽  
pp. 314-324 ◽  
Author(s):  
Richard C. Playle ◽  
Greg G. Goss ◽  
Chris M. Wood
Keyword(s):  
Rainbow Trout ◽  
Water System ◽  
Respiratory Acidosis ◽  
Carbon Dioxide Tension ◽  
Soft Water ◽  
Cell Swelling ◽  
Salmo Gairdneri ◽  
Flow Through ◽  
Respiratory Gases ◽  
Respiratory Toxicity

Rainbow trout (Salmo gairdneri) fitted with dorsal aortic cannulae were exposed in a flow-through soft water system to three acidities (pH 5.2, 4.8, or 4.4) and two concentrations of Ca (45 or 410 μequiv.∙L−1), in the presence (105 μg∙L−1) or absence of Al. Blood was sampled for respiratory gases, ions, metabolites, and hematology before and at 4, 18, 28, 42, and 66 h exposure. Two toxic mechanisms of Al and acidity were seen: (i) ionoregulatory toxicity, which was caused by Al at pH 5.2 and 4.8 and by acidity at pH 4.4, and (ii) respiratory toxicity, which was caused solely by Al, and was greatest at higher pH. Ionoregulatory toxicity involved decreases in plasma Na+ and Cl−, red cell swelling, and hemoconcentration. Respiratory toxicity involved reduced blood oxygen tension, elevated blood carbon dioxide tension, and increases in blood lactate. Blood acidosis was a combination of respiratory acidosis (due to CO2 accumulation in the blood; higher pH exposures) and metabolic acidosis (probably due to differential Na+ and Cl− loss into the external, acidic environment; lower pH exposures). Higher water Ca reduced ionoregulatory disturbances due to acidity alone but not those due to Al at higher pH. Higher water Ca also reduced respiratory disturbances at lower pH but not at higher pH. The results are discussed with reference to the chemistry of Al and changes in the gill epithelium associated with acid and Al exposure.

The effects of zinc on rainbow trout (Salmo gairdneri) in hard and soft water

1974 ◽  
Vol 12 (2) ◽  
pp. 193-201 ◽  
Author(s):  
James R. Sinley ◽  
John P. Goettl ◽  
Patrick H. Davies
Keyword(s):  
Rainbow Trout ◽  
Soft Water ◽  
Salmo Gairdneri

Measurement of vitellogenin from rainbow trout by rocket immunoelectrophoresis: application to the kinetic analysis of estrogen stimulation in the male

1985 ◽  
Vol 63 (9) ◽  
pp. 982-987 ◽  
Author(s):  
Jean Louis Maitre ◽  
Catherine Le Guellec ◽  
Stephane Derrien ◽  
Martin Tenniswood ◽  
Yves Valotaire
Keyword(s):  
Rainbow Trout ◽  
Salmo Gairdneri ◽  
Immature Female ◽  
External Appearance ◽  
Seasonal Regulation ◽  
Low Levels ◽  
Estrogen Stimulation ◽  
Different Levels ◽  
Estradiol Levels ◽  
Stimulation Of

The study of the seasonal regulation of vitellogenesis in rainbow trout (Salmo gairdneri) is hampered by two features of the system which are not seen in species such as Xenopus. First, it is impossible to sex immature trout by external appearance and, secondly, the quantitation of the very low levels of vitellogenin in previtellogenic serum is technically difficult and tedious. We describe the preparation of a specific, sensitive anti-vitellogenin antibody and the use of this antibody in a rocket immunoelectrophoresis system to measure serum vitellogenin. The sensitivity of the assay is such that, using only 2 μL of serum, it is possible to detect vitellogenin at levels of 10 μg/mL, making this assay extremely useful for selecting immature female trout for further studies on the basis of the presence of vitellogenin. Using this system we have also measured the response of individual male trout to stimulation with different levels of estradiol, and we have shown that it is possible to measure the stimulation of vitellogenin by estradiol levels equivalent to those seen during the previtellogenic phase of the reproductive cycle in females. This simple assay system thus alleviates two of the major hurdles in studying vitellogenesis in trout.

Sign in / Sign up

Export Citation Format

Share Document