Visual pigment changes in the rainbow trout, Salmo gairdneri

1972 ◽  
Vol 50 (8) ◽  
pp. 1117-1126 ◽  
Author(s):  
W. L. Jacquest ◽  
D. D. Beatty
Keyword(s):  
Rainbow Trout ◽  
Visual Pigment ◽  
Intramuscular Injection ◽  
Visual Pigments ◽  
The Other ◽  
Salmo Gairdneri ◽  
Thyrotropic Hormone

The retinae of rainbow trout, Salmo gairdneri, have mixtures of two visual pigments, one based on retinaldehyde (VP5031), the other on 3-dehydroretinaldehyde (VP5272). Increases in the proportion of VP5272 or maintained high percentages of VP5272 were induced in three ways: (1) feeding a diet rich in 3-dehydroretinol; (2) intraperitoneal injections of L-thyroxine; and (3) intramuscular injection of bovine thyrotropic hormone. The possible significance of these findings in relation to carotenoid conversions in fish is discussed.

Changes in the visual pigments of trout

1973 ◽  
Vol 51 (9) ◽  
pp. 901-914 ◽  
Author(s):  
Donald M. Allen ◽  
William N. McFarland ◽  
Frederick W. Munz ◽  
Hugh A. Poston
Keyword(s):  
Rainbow Trout ◽  
Brown Trout ◽  
Visual Pigment ◽  
Brook Trout ◽  
Forest Canopy ◽  
Environmental Control ◽  
Cutthroat Trout ◽  
Visual Pigments ◽  
Salmo Gairdneri ◽  
Canopy Access

The proportions of two visual pigments (rhodopsin and porphyropsin) were examined in four species of trout under experimental and natural conditions. Brook trout (Salvelinus fontinalis), rainbow trout (Salmo gairdneri), and brown trout (Salmo trutta) have different relative proportions of visual pigments in their retinae. The visual pigment balance in wild cutthroat trout (Salmo clarki) is related to forest canopy (access to light) and season. The brown trout have a more red-sensitive and less labile pair of visual pigments than brook or rainbow trout, which respond to photic conditions by increasing the proportion of porphyropsin (in light) and increasing rhodopsin (in darkness). The brown trout have a high percentage of porphyropsin, regardless of experimental conditions. This result does not reflect an inability to form rhodopsin but rather may relate to a consistently high proportion of 3-dehydroretinol in the pigment epithelium. The possible advantages and mechanisms of environmental control of trout visual pigment absorbance, as currently understood, are discussed.

A Standardized Model of Experimental Furunculosis in Rainbow Trout (Salmo gairdneri)

1980 ◽  
Vol 37 (4) ◽  
pp. 746-750 ◽  
Author(s):  
C. Michel
Keyword(s):  
Rainbow Trout ◽  
Intramuscular Injection ◽  
Infected Fish ◽  
Aeromonas Salmonicida ◽  
Salmo Gairdneri ◽  
Exponential Growth Phase ◽  
Cell Counts ◽  
Viable Cells ◽  
Treated Fish ◽  
Drop Plate

With the aid of published information, we have developed a standardized and reproducible experimental model of furunculosis in rainbow trout (Salmo gairdneri). The infective doses (LD50 = 200 to 2000 germs, i.m.) employed strains of Aeromonas salmonicida, the virulence of which was maintained by passage in 15-g fingerlings. The number of viable cells in the dose was conveniently determined using the drop-plate enumeration technique; however, meaningful cell counts could only be obtained if broth cultures used for infecting the fish were harvested early in the exponential growth phase (OD < 1.000 at 525 nm). Better results were obtained with intramuscular injection than with intraperitoneal injection. The infection procedure involved injecting a dose of 10 LD50, intramuscularly, into each of 30 fish held at 15 °C and recording the mortalities for 10 d. Protection tests in which Tribrissen (28 mg sulfadiazine and 5.6 mg trimethoprim/kg fish for 8 d) was fed or tetracycline (1 mg per fish) i.m. injected into the infected fish served to demonstrate the value of the model. Results were in agreement with field observations with no death for treated fish and a mortality of 96%, for untreated fish. Key wordss rainbow trout, Salmo gairdneri; Aeromonas salmonicida, furunculosis, experimental infection

pHi, contractility and Ca-balance under hypercapnic acidosis in the myocardium of different vertebrate species

1982 ◽  
Vol 96 (1) ◽  
pp. 405-412
Author(s):  
H. Gesser ◽  
E. Jorgensen
Keyword(s):  
Rainbow Trout ◽  
Negative Inotropic Effect ◽  
The Other ◽  
Inotropic Effect ◽  
Salmo Gairdneri ◽  
Hypercapnic Acidosis ◽  
Hydrogen Ions ◽  
Vertebrate Species ◽  
High Co2 ◽  
Intracellular Ca

The influence of hypercapnic acidosis upon the heart was examined in four vertebrate species. The CO2 in the tissue bath was increased from 2.7 to 15% at 12 degrees C for flounder (Platichthys flesus) and cod (Gadus morhua) and from 3 to 13% at 22 degrees C for turtle (Pseudemys scripta) and rainbow trout (Salmo gairdneri). During hypercapnia, as previously described, there was a decline and recovery of contractility in heart strips of flounder and turtle, and a sustained decrease in cod and rainbow trout. At high CO2 the increase in contractile force following increases in the extracellular Ca-concentration were smaller for the cod myocardium than for the other myocardia. The intracellular pH (pHi), measured with the DMO method, in heart strips of turtle and trout was significantly lower at high than at low CO2. This acidifying effect expressed as the increase in the intracellular concentration of hydrogen ions was larger in the turtle than in the trout myocardium. Intracellular Ca-activity, measured by efflux of 45Ca from preloaded heart strips, was unaffected by high CO2 in trout, but was raised in the other three species. Thus the ability to counteract the negative inotropic effect of hypercapnia is apparently not due to cellular buffering or extrusion of hydrogen ions. More probably it involves (a) a release of intracellular Ca; (b) a positive inotropic effect of an increase in intracellular Ca-activity.

Response of Wild Rainbow (Salmo gairdneri) and Cutthroat Trout (S. clarki) to Stocked Rainbow Trout in Fertile and infertile Streams

1988 ◽  
Vol 45 (12) ◽  
pp. 2087-2105 ◽  
Author(s):  
C E. Petrosky ◽  
T. C. Bjornn
Keyword(s):  
Rainbow Trout ◽  
Mortality Rate ◽  
Survival Rates ◽  
Cutthroat Trout ◽  
The Other ◽  
Salmo Gairdneri ◽  
Summer Mortality ◽  
Wild Trout ◽  
Stocking Rates

Wild rainbow trout (Salmo gairdneri) and cutthroat trout (S. clarki) were unaffected by stocking of catchable-size rainbow trout in two Idaho streams, except at the highest stocking rates, and even then the effects were limited. In the infertile stream, stocking 50 or 150 trout per section (doubling or tripling the density) did not reduce the abundance of wild cutthroat trout. Wild trout abundance declined at a faster rate in an unreplicated section stocked with 500 trout than in unstocked sections. In the fertile stream, stocking 50 or 100 hatchery trout in sections containing 26–120 similar-sized wild trout did not increase the dispersion or reduce the abundance, growth, or survival rates of wild rainbow trout. When we stocked 400 trout (100 on four dates) in sections containing 32–53 tagged wild trout of similar size, the summer mortality rate of wild trout was higher in stocked than in unstocked sections; the other parameters were not significantly different.

Introgressive Hybridization in Populations of Paiute Cutthroat Trout (Salmo clarki seleniris)

1981 ◽  
Vol 38 (8) ◽  
pp. 939-951 ◽  
Author(s):  
Craig A. Busack ◽  
G. A. E. Gall
Keyword(s):  
Population Structure ◽  
Rainbow Trout ◽  
Introgressive Hybridization ◽  
Cutthroat Trout ◽  
The Other ◽  
Salmo Gairdneri ◽  
Electrophoretic Data ◽  
The Difference ◽  
Salmo Clarki ◽  
Two Populations

Two populations of Paiute cutthroat trout (Salmo clarki seleniris) were compared meristically and electrophoretically with Lahontan cutthroat (S. c. henshawi) and rainbow trout (S. gairdneri) to elucidate population structure and verify the occurrence of introgressive hybridization. In Silver King Creek, both meristic and electrophoretic evidence indicated two populations were present, one appearing to be pure Paiute cutthroat, the other Paiute cutthroat introgressed with rainbow trout. Lahontan cutthroat introgression was a possibility in Silver King Creek but could not be evaluated because of the strong meristic and electrophoretic similarity of Paiute and Lahontan cutthroat. The other Paiute population, Cottonwood Creek, meristically appeared to be pure Paiute cutthroat but electrophoretic data indicated it was introgressed with rainbow trout. The existence of the two Silver King Creek populations indicated introgression was incomplete in that stream; introgression appeared to be complete in Cottonwood Creek. The meristic similarity of Cottonwood Creek trout to pure Paiute cutthroat was probably a result of strong selection by management agencies for a Paiute cutthroat phenotype. Electrophoresis was more discriminating than meristic analysis in this study in detecting introgression. Electrophoresis also allowed more detailed analysis of population structure than meristics because of the difference in complexity of the genetic systems analyzed by the two techniques. However, the application of both techniques contributed greatly to our understanding of introgression in the Paiute cutthroat and demonstrated the complementarity of the two approaches.Key words: Salmo clarki, Salmo gairdneri, Paiute cutthroat, Lahontan cutthroat, meristics, electrophoresis, introgression, hybridization, gametic disequilibrium, principal components

scholarly journals The Function of Photomechanical Movements in the Retina of the Rainbow Trout (Salmo Gairdneri)

1982 ◽  
Vol 96 (1) ◽  
pp. 389-403 ◽  
Author(s):  
R. H. DOUGLAS
Keyword(s):  
Rainbow Trout ◽  
Dark Adaptation ◽  
Visual Pigment ◽  
Time Course ◽  
Temporal Correlation ◽  
Salmo Gairdneri ◽  
Direct Sunlight ◽  
Pigment Concentrations ◽  
Wave Sensitivity ◽  
Effect Of Light

1. The function of photomechanical movements in the retina of rainbow trout (Salmo gairdneri) was investigated by determining both the effect of light on the level of extractable visual pigment, and the electroretinographic b-wave sensitivity, during various stages of photomechanical light and dark adaptation. 2. Dark-adapted fish, light-adapted fish, and dark-adapted fish exposed to ten minutes direct sunlight had on average visual pigment concentrations of 100, 82 and 36% respectively. 3. The intensity of illumination required to bleach a specified amount of visual pigment in the light-adapted retina was found to be 1.29 log units higher than that needed to bleach the same amount of visual pigment in a dark-adapted eye. 4. The level of extractable visual pigment was observed to be relatively constant over natural twilight periods. 5. A close temporal correlation was observed between the time course of electroretinographic adaptation, measured by the b-wave sensitivity, and photomechanical changes. 6. All these observations tend to support the hypothesis that photomechanical movements serve, at least in part, to protect the rod visual pigment from overstimulation in the light-adapted retina.

Seasonal change in the amount of visual pigment in the retinae of fish

1982 ◽  
Vol 60 (3) ◽  
pp. 281-287 ◽  
Author(s):  
Donald M. Allen ◽  
Ellis R. Loew ◽  
William N. McFarland
Keyword(s):  
Seasonal Change ◽  
Constant Temperature ◽  
Visual Pigment ◽  
Salmo Trutta ◽  
Salvelinus Fontinalis ◽  
Visual Pigments ◽  
Salmo Gairdneri ◽  
Concomitant Increase ◽  
Retinal Photoreceptors ◽  
The Way

The total amount of two visual pigments, rhodopsin and porphyropsin, extracted from retinal photoreceptors of three trouts and a cyprinid, changes seasonally. In Salmo gairdneri, Salmo trutta, and Salvelinus fontinalis maintained in an outdoor raceway at constant temperature (8 °C) the total amount of visual pigment increased about twofold during the winter, though the proportions of rhodopsin and porphyropsin were relatively unchanged. In eastern common shiners, Notropis cornutis, sampled from a stream, visual pigment increased by about fourfold in winter as compared with summer, and porphyropsin rose from about 17 to 68% of the total amount. A later sample of summer and winter shiners revealed no difference in the density of visual pigment within individual rods.An increased amount of visual pigment will broaden the overall pigment absorptance spectrum and a concomitant increase in porphyropsin will further broaden and shift absorptance toward longer wavelengths. Thus, change in total amount of visual pigment represents a new dimension in the way that visual pigment absorptance can be dynamically altered in certain fishes.

scholarly journals The Effect of Hypoxia and Anaemia on the Swimming Performance of Rainbow Trout (Salmo Gairdneri)

1971 ◽  
Vol 55 (2) ◽  
pp. 541-551 ◽  
Author(s):  
DAVID R. JONES
Keyword(s):  
Rainbow Trout ◽  
High Temperature ◽  
Low Temperature ◽  
Swimming Performance ◽  
Metabolic Cost ◽  
Water Velocity ◽  
The Other ◽  
Salmo Gairdneri ◽  
Water Tunnel ◽  
Significant Difference

1. A series of increasing water-velocity tests in a water tunnel has been used to investigate the maximum swimming performance of two groups of rainbow trout, one acclimated to high temperature (21-23 °C) and the other to low temperature (8-10 °C). 2. At temperatures close to their acclimation temperatures there was no significant difference between the maximum swimming speeds of the two groups of trout. 3. Exposure to an environmental oxygen tension of half the air-saturation value resulted in a 43 % reduction in maximum swimming performance at low temperature and a 30 % reduction at high temperature compared with normal animals. 4. Reduction in haematocrit to one-half or one-third normal resulted in a 34% reduction in maximum swimming speed at low temperature and a 40% reduction at high temperature compared with control animals (blank injected). 5. The results are discussed in terms of whether fish can be assumed to be in a steady state at all velocities below the critical velocity and whether it is possible to attribute the differences in performance, during anaemia and hypoxia, to increased metabolic cost of the cardiac and branchial pumps.

Measurements of serum thyroxine and the proportions of rhodopsin and porphyropsin in rainbow trout

1977 ◽  
Vol 55 (5) ◽  
pp. 836-842 ◽  
Author(s):  
Donald M. Allen
Keyword(s):  
Rainbow Trout ◽  
Visual Pigment ◽  
Salmo Gairdneri ◽  
Serum Thyroxine

Immersion of yearling rainbow trout (Salmo gairdneri) in 0.1 or 1.0 ppm quantities of thyroxine (T4) significantly increased both T4 in the serum and the proportion of porphyropsin visual pigment in the retina. In fish not treated with T4, levels of porphyropsin were higher at 6 °C than at 14 °C. However, under different conditions of light or temperature there was no consistent correlation between serum T4 and percentage of porphyropsin. Furthermore, there was no tendency for individuals higher in porphyropsin to have higher titre of T4, or vice versa. The results generally do not support the hypothesis that serum T4 titre and porphyropsin are physiologically interdependent.

Sign in / Sign up

Export Citation Format

Share Document