Potassium turnover was studied in rainbow trout, Salmo gairdneri Richardson, adapted to fresh water or 22 %o sea water using K and Rb. Potassium space of the whole body increased with time and was about 5 mmol kg" after 20h, while Rb space under the same conditions was only about 0-5 mmol kg", indicating slow penetration of body K by Rb + , especially in muscle and red blood cells. Potassium in...

The red cell adrenoceptor affinity for the unspecific agonists adrenaline and noradrenaline and the specific beta-agonist isoprenaline was studied in vitro on whole blood of rainbow trout, Salmo gairdneri at 15 degrees C. The erythrocytic adrenoceptors could be pharmacologically characterized as beta-receptors of the 'noradrenaline'-type (beta 1-type), with an order of potency of isoprenaline g...

Chinook salmon, Oncorhynchus tshawytscha (Walbaum), and rainbow trout, Salmo gairdneri Richardson, were used to determine if sublethal copper exposure would increase their susceptibility to Vibrio anguillarum infection. Eish were pretreated with copper at fractional levels of the 96 h copper LC50 before exposure to the pathogen. Mortality by vibriosis was greater among fish exposed to 9/0 of th...

Groups of rainbow trout (Salmo gairdneri; mean weight 5 g) were given diets containing 10, 12, 14, 17, 21, 24 and 26 g lysine/kg diet for 12 weeks. By analysis of the growth values the dietary requirement of lysine in this experiment was found to be 19 g/kg diet. A similar requirement value was obtained from a dose-response curve of expired 14CO2 (following an intraperitoneal injection of L-[U-...

RANDALL, D. J., AND J. N. CAMERON. Respiratory control of arterial pH as temperature changes in rainbow trout Salmo gairdneri. Am. J. Physiol. 225(4) : 997-1002. 1973.-Arterial blood pH decreased as temperature increased, dpH/dT was 0.017 unit/“C and was independent of the acclimation history of the fish. Ventilation volume increased in proportion to oxygen uptake with temperature. Changes in w...

We have investigated the morphological effects of a genetic locus, Pgm1-t, that affects the expression of a phosphoglucomutase locus (Pgm1) in liver of rainbow trout (Salmo gairdneri). We have previously shown that embryos with liver Pgm1 expression hatch earlier than those without liver Pgm1 expression. We predicted that this difference in developmental rate should cause a reduction in meristi...

Myocardial intracellular pH was measured in a perfused rainbow trout, Salmo gairdneri, with DMO (5,5-dimethyl-2,4-oxazlidinedione), to test the hypothesis that catecholamines promote active regulation of myocardial pH in order to protect contractility during a respiratory acidosis comparable to that observed after exercise. Under control conditions (extracellular pH = 8.0; PCO2 = 2 Torr), myoca...

Attempts were made to examine the ichthyotoxicity of paralytic shellfish poison (PSP) in sixteen species of marine and freshwater fishes. Most of them showed minimum lethal doses (LD100) ranging from 1-8 MU/20g body weight when injected with a partially purified PSP intra peritoneally. Exceptionally, several fishes such as a goby Acanthogobius flavimanus (LD100, 9-17 MU/20g) and puffer Fugu nip...

A dorsal cannulation technique is described. It has been employed for repeated blood sampling in unanaesthetized rainbow trout (Salmo gairdneri) kept singly in special receptacles described in the paper. The level of the studied haematological parameters (Haematocrit, Hb, glucose, lactate, K+, Na+, Ca2+) differed between fish kept in receptacles for 1 week and free-swimming fish, most probably ...

Paralongicollum nemacheili n. gen., n. sp. is described from Salmo gairdneri Richardson and Nemacheilus stoliczkai Steindacher in Lake Kul'say in the basin of Lake Balkhash, Kazakh S.S.R. Its long uniformly cylindrical neck and nonfiliform proboscis distinguish it from the other 3 genera of the family. Tenuiproboscis Yamaguti, 1935, has a filiform proboscis. The neck of Pomphorhynchus Monticell...