Maximum Tolerable Level, Digestion, and Metabolism of D-Glucose (Cerelose) in Rainbow Trout (Salmo gairdneri) Reared on a Practical Trout Diet

1982 ◽  
Vol 39 (9) ◽  
pp. 1229-1234 ◽  
Author(s):  
J. W. Hilton ◽  
J. L. Atkinson ◽  
S. J. Slinger
Keyword(s):  
Rainbow Trout ◽  
Water Temperature ◽  
Glucose Level ◽  
Energy Content ◽  
Liver Glycogen ◽  
Salmo Gairdneri ◽  
Dietary Energy ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Increased Activity ◽  
Tolerable Level

The maximum tolerable dietary level, digestion, and metabolism of D-glucose (cerelose) were investigated in rainbow trout (Salmo gairdneri) reared on practical diets containing optimum protein and lipid levels at two different water temperatures for 12 wk. Liver glycogen levels (LG) and liver:body weight ratios (LB) initially increased with increasing dietary glucose, but leveled off above 10–15% glucose. The plateauing of LB and LG was consistent with the plateauing of liver glucose-6-phosphate dehydrogenase activity (G6PD) and probably overall hexose monophosphate shunt (HMS) activity at high dietary levels of glucose. This indicates that there may be an optimum ratio of digestible carbohydrate to lipid in salmonid diets. LG and LB tended to be higher in trout reared upon the same dietary glucose level in fish reared at 11 °C as compared with those at 15 °C. This may have been caused by increased activity of the HMS as indicated by increased activity of liver G6PD in fish acclimated to 11 °C as compared to trout reared at 15 °C on the same dietary glucose level (when assayed at 15 °C). The digestion coefficient of glucose was uniformly high (96–99%) and not affected by either dietary glucose level (up to 25% of the diet) or water temperature (11 or 15 °C). The maximum tolerable level of glucose in salmonid diets appears to be dependent upon the protein, lipid, and overall energy content of the diet.Key words: trout, glucose digestion, glucose metabolism, maximum tolerable levels, water temperature, dietary energy

scholarly journals Response of rainbow trout (Salmo gairdneri) to increased levels of available carbohydrate in practical trout diets

1982 ◽  
Vol 47 (3) ◽  
pp. 597-607 ◽  
Author(s):  
J. W. Hilton ◽  
J. L. Atkinson
Keyword(s):  
Body Weight ◽  
Rainbow Trout ◽  
Weight Gain ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Liver Glycogen ◽  
Salmo Gairdneri ◽  
Dietary Carbohydrate ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Percentage Conversion ◽  
Different Levels

1. The physiological response of rainbow trout (Salmo gairdneri) reared on different levels of available carbohydrate in practical trout diets having the same levels of energy and nitrogen for 16–24 weeks was determined.2. Weight gain was significantly reduced in trout reared on the highest level of available carbohydrate, 210 g cerelose (α-glucose)/kg, and there was a significant linear regression (R2 0.88) of dietary carbohydrate on weight gain.3. Liver: body-weight values and liver glycogen levels increased in relation to increased dietary carbohydrate.4. Liver glucose-6-phosphate dehydrogenase (EC 1.1.1.49) activity increased and liver phosphoenolpyruvate carboxykinase (EC 4.1.1.32) activity decreased per kg body-weight of fish with increasing dietary carbohydrate. However, no significant effect was noted on the activity of these liver enzymes above a dietary cerelose level of 140 g/kg.5. Liver fructose diphosphatase (EC 3.1.3.11) activity increased with increasing dietary carbohydrate has been interpreted as meaning a recycling of triosephosphate to glucose-6-phosphate.6. Dietary carbohydrate level had no significant effect on the liver pyruvate kinase (EC 2.7.1.40) activity, the rate of glucose utilization or the percentage conversion of [14C]alanine to glucose in the plasma of trout.7. The results indicate that rainbow trout have a limited ability to adapt to increased dietary carbohydrate and a level in excess of 140 g/kg of the diet is not efficiently utilized.

Changes in plasma insulin and carbohydrate metabolism of zinc-stressed rainbow trout, Salmo gairdneri

1982 ◽  
Vol 60 (9) ◽  
pp. 2079-2084 ◽  
Author(s):  
G. F. Wagner ◽  
B. A. McKeown
Keyword(s):  
Rainbow Trout ◽  
Pancreatic Beta Cells ◽  
Plasma Insulin ◽  
Zinc Sulphate ◽  
Liver Glycogen ◽  
Salmo Gairdneri ◽  
Control Group ◽  
Exposed Fish ◽  
Glucose Levels ◽  
Insulin Radioimmunoassay

An experiment was conducted to determine if the hyperglycemia that is observed in zinc-stressed fish is also accompanied by changes in the levels of plasma insulin and liver glycogen. Juvenile rainbow trout were exposed to three concentrations of zinc sulphate along with a control group over 31 days. Plasma glucose levels were monitored in each group over the course of the experiment. The group demonstrating the most acute and sustained hyperglycemia (0.352 ppm zinc) was then analyzed along with the controls for changes in plasma insulin (using a teleost insulin radioimmunoassay) and liver glycogen levels. Significant depressions in plasma insulin and liver glycogen levels were observed in the zinc-exposed fish when compared with the controls. These changes are discussed with respect to possible influences of epinephrine, which is elevated in stressed fish, and (or) a direct effect of zinc metal on the pancreatic beta cells.

Effect of Temperature on Accumulation of Methylmercuric Chloride and p,p′DDT by Rainbow Trout (Salmo gairdneri)

1974 ◽  
Vol 31 (10) ◽  
pp. 1649-1652 ◽  
Author(s):  
Robert E. Reinert ◽  
Linda J. Stone ◽  
Wayne A. Willford
Keyword(s):  
Rainbow Trout ◽  
Water Temperature ◽  
Effect Of Temperature ◽  
Salmo Gairdneri ◽  
Methylmercuric Chloride ◽  
Concentration Factors

Amounts of mercury and DDT residues accumulated from water by yearling rainbow trout (Salmo gairdneri) in the laboratory increased as water temperature increased. Fish exposed to methylmercuric chloride at concentrations of 234–263 parts per trillion for 12 wk at 5, 10, and 15 C accumulated 1.19, 1.71, and 1.96 ppm; fish exposed to p,p′DDT at concentrations of 133–176 parts per trillion accumulated 3.76, 5.93, and 6.82 ppm. Concentrations of mercury accumulated by the fish were significantly different (P < 0.01) at each of the three temperatures, and the concentrations of DDT were significantly different at 5 and 10 and 5 and 15 C. Throughout the period of exposure, the concentration factors (concentration of contaminant in the fish/concentration in water) at each of the three temperatures were far higher for p,p′DDT than for methylmercuric chloride.

Endrin Toxicosis in Rainbow Trout (Salmo gairdneri)

1973 ◽  
Vol 30 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Blake F. Grant ◽  
Paul M. Mehrle
Keyword(s):  
Rainbow Trout ◽  
Total Protein ◽  
Serum Cortisol ◽  
Liver Glycogen ◽  
Salmo Gairdneri ◽  
Protein Distribution ◽  
Serum Electrolytes ◽  
Electrophoretic Patterns ◽  
Sublethal Doses ◽  
High Doses

In mature rainbow trout (Salmo gairdneri) receiving sublethal doses of endrin (4.3–145 × μg/kg body wt/day in 0.215–7.25 mg/kg of food) for 163 days and then forced to swim for 1 hr, the insecticide affected serum electrolytes, osmolality, total protein, cholesterol, cortisol, lactate, glucose, liver glycogen, and growth. Forced swimming alone altered 9 of 16 serum parameters examined. Apparent increases in serum Na and Cl and significant increases in osmolality and liver glycogen were directly related to dosage. A biphasic distribution of phosphate, total protein, and cholesterol with dosage was apparent. Glucose was increased about 50% by 145 μg/kg but was unaffected by lower doses. Variance analysis of zone electrophoretic patterns disclosed an in teraction between serum protein distribution and dose. Mobilization of liver glycogen was apparently inhibited by low doses and almost totally blocked by high doses. Correspondingly, trout given 14.5 μg/kg or more had lowered serum cortisol levels whereas the lowest dose elevated cortisol. Growth was inhibited appreciably by 145 μg/kg but not by lower doses. Visceral fat accumulated 4.8–8.7 μg endrin/g tissue in the 43 and 145 μg/kg exposures. We conclude that endrin caused dysfunction of physiologic processes critical to survival.

Investigation sur la toxicodynamique du cyanure et sur sa biotransformation chez la truite arc-en-ciel (Salmo gairdneri)

1986 ◽  
Vol 43 (10) ◽  
pp. 2017-2024 ◽  
Author(s):  
Pierre Raymond ◽  
Gérard Leduc ◽  
Jack A. Kornblatt
Keyword(s):  
Rainbow Trout ◽  
Blood Plasma ◽  
Cytochrome Oxidase ◽  
Liver Glycogen ◽  
Effective Concentration ◽  
Salmo Gairdneri ◽  
Pasteur Effect

The exposure of rainbow trout (Salmo gairdneri) to 0.01, 0.02 and 0.03 mg HCN∙L−1 for 20 d demonstrated the biotransformation of HCN into thiocyanate which accumulated in the blood plasma which increased the duration of exposure to cyanide. Despite its transformation into thiocyanate, there is still a sufficient quantity of cyanide to inhibit cytochrome oxidase by 60–80% within the first 24 h of exposure. This level of inhibition remained stable during the 20 d of the tests and was the same at the three concentrations tested. This observation permits the prediction of effective concentration of free HCN inside the fish. The measurements of liver glycogen levels illustrate the Pasteur effect in the rainbow trout subjected to cyanide. During cyanide exposure, liver glycogen was rapidly used, particularly at 0.03 mg HCN∙L−1 whereas at 0.01 and 0.02 mg HCN∙L−1 the glycogen levels gradually came back to normal after 7–10 d of exposure.

On the Function of the White Muscles in Teleosts at Intermediate Swimming Speeds

1973 ◽  
Vol 58 (2) ◽  
pp. 509-522 ◽  
Author(s):  
RICHARD C. L. HUDSON
Keyword(s):  
Rainbow Trout ◽  
Linear Relationship ◽  
Muscle Mass ◽  
Swimming Performance ◽  
Beat Frequency ◽  
Salmo Gairdneri ◽  
Electrical Activities ◽  
Tail Beat ◽  
Increased Activity

1. The swimming performance of rainbow trout, Salmo gairdneri, and the electrical activities, recorded extracellularly, of its red and mosaic muscles have been studied at different swimming speeds. 2. A linear relationship was found between the specific velocity (body lengths/sec) and the frequency of tail beating at frequencies up to 5/sec. 3. The red muscles are active at all swimming speeds at which the fish swim by tail oscillations. Discharges from this muscle decrease in duration with frequency up to 3.5-5.0 beats/sec and then increase while the interburst interval decreases linearly with tail-beat frequency. 4. Mosaic muscle becomes active at 3.05-3.60 tail beats/sec and increases slightly with increasing frequency of tail oscillations. Greatly increased activity was recorded in response to struggling and rapid accelerations. 5. The white (mosaic) muscle mass of teleosts is concluded to be involved at intermediate swimming speeds and to be active at the higher range of cruising speeds.

Sign in / Sign up

Export Citation Format

Share Document