Renal portal phagocytosis of bacteria in rainbow trout (Salmo gairdneri Richardson): ultrastructural observations

1984 ◽  
Vol 62 (12) ◽  
pp. 2505-2511 ◽  
Author(s):  
H. W. Ferguson
Keyword(s):  
Endothelial Cells ◽  
Electron Microscope ◽  
Rainbow Trout ◽  
Salmo Gairdneri ◽  
Portal Circulation ◽  
Prominent Feature ◽  
Large Area ◽  
Large Numbers

Catheterized rainbow trout (Salmo gairdneri) were inoculated with killed bacteria and the perfused – fixed kidney was examined in the electron microscope. The endothelium of the portal circulation was continuous but had evidence of marked pinocytotic activity with large numbers of intracytoplasmic vesicles, many of which were spiny coated. Intracytoplasmic transfer tubules were also a prominent feature. Bacteria were phagocytosed by macrophages closely associated with the endothelium, but not by the endothelial cells. Macrophage pseudopodia were occasionally seen traversing endothelium to touch the underlying haemopoietic tissue. The renal portal vasculature provides a large area for efficient antigen trapping.

Competition for Food Between Redside Shiners (Richardsonius balteatus) and Rainbow Trout (Salmo gairdneri) in Two British Columbia Lakes

1961 ◽  
Vol 18 (2) ◽  
pp. 203-220 ◽  
Author(s):  
R. E. Johannes ◽  
P. A. Larkin
Keyword(s):  
British Columbia ◽  
Rainbow Trout ◽  
Interspecific Competition ◽  
Stomach Contents ◽  
Salmo Gairdneri ◽  
Interspecific Aggression ◽  
Large Numbers ◽  
Competition For Food ◽  
Biological Environment ◽  
Richardsonius Balteatus

The distribution, movements, behaviour and food of trout and shiners in Paul and Pinantan Lakes were studied to determine the items and mechanisms of interspecific competition between them. Data from recent years were compared with data for years when trout alone inhabited the lakes.No interspecific aggression was observed. The possibility that the two species were competing for space was discounted. Stomach contents of shiners in Pinantan Lake revealed a marked qualitative diurnal food cycle. In Paul Lake, shiners have drastically reduced the Gammarus population relative to its pre-shiner abundance, forcing trout, as well as the shiners themselves, to shift their diets to other foods. This overgrazing was caused by the concentration of large numbers of shiners over the shoals where Gammarus are also present in their highest concentrations, and the ability of shiners to pursue food deeper into the weeds and to graze an area more thoroughly than trout. In Pinantan Lake, shiners have apparently reduced the density of Daphnia to a point where trout are unable to feed on them as rapidly as in pre-shiner years. The ability of both species to utilize many types of food tends to reduce the intensity of competition.The study demonstrates how false implications may arise from an appraisal of competition not initiated until after the effects of competition have been observed. If observations had not been made on Paul Lake until after competition had been observed, the importance of Gammarus as an item of competition would probably have been overlooked and the whole competitive relationship misconstrued.Environmental factors and behaviour were shown to be important influences on the dynamics of competition. The physical and biological environment and the distribution and behaviour of competitors may be in states of continual flux in which case the niches of the competitors cannot be considered constant.

Ultrastructure of the granule cells in the small intestine of the rainbow trout (Salmo gairdneri) before and after stratum granulosum formation

1983 ◽  
Vol 61 (1) ◽  
pp. 133-138 ◽  
Author(s):  
T. Bergeron ◽  
Bill Woodward
Keyword(s):  
Rainbow Trout ◽  
Developmental Stages ◽  
Granule Cells ◽  
Protein S ◽  
Salmo Gairdneri ◽  
Stratum Granulosum ◽  
Cytoplasmic Granules ◽  
Large Numbers ◽  
Before And After ◽  
Juvenile Trout

The ultrastructure of the small intestinal granule cells (GC) of the rainbow trout (Salmo gairdneri) was studied in fry and fingerlings before the cells organized to form the stratum granulosum (SG) and in 12-month-old juveniles which possess a well-developed SG several cell diameters in thickness. The GC of juvenile trout exhibit a striking reduction in nucleolar numbers and in the quantity of rough endoplasmic reticulum relative to the GC of younger fish, but contain even greater numbers of large, electron-dense cytoplasmic granules. The final stages of cellular maturation therefore take place in the GC after their organization to form a layer, and the cells appear to lose their capacity to synthesize protein(s) for the cytoplasmic granules. Since the latter structures are, nevertheless, maintained in large numbers in mature GC, it is suggested that they function intact within the cell. No precursor to the granulated form of the GC was identified in the intestine, a result which suggests that the earliest developmental stages of the GC locate within another organ.

Selective Sampling and Orientation of Non-Homogeneous Tissues

1968 ◽  
Vol 26 ◽  
pp. 98-99
Author(s):  
C. C. Clawson ◽  
L. W. Anderson ◽  
R. A. Good
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Light Microscopy ◽  
Random Sampling ◽  
New Method ◽  
Microscope Examination ◽  
Small Areas ◽  
Selective Sampling ◽  
Large Numbers ◽  
Specific Orientation

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.

Ultramicroscopic and Coagulation-Fibrinolytic Findings Induced by Tissue Thromboplastin

1979 ◽  
Author(s):  
H Nagata ◽  
T Seya ◽  
Y Oguma ◽  
M Yamauchi ◽  
T Murakoshi ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Hypercoagulable State ◽  
Membrane Structures ◽  
Transmission Electron ◽  
Single Sheet ◽  
Tissue Thromboplastin ◽  
Short Time

We have studied the ultrastructures of tissue thromboplastin (T.Tbp) to demonstrate how It changes during coagulation.[Materials and Methods] T.Tbp from lungs of rabbits was used for these studies. It was injected into ear veins of rabbits. Lungs were resected at several seconds, 10sec, 1 min, 5 min, 24 hrs or 48 hrs after the injection. They were examined by transmission electron microscope.[Results] Concentrically arranged membrane structures of the injected T.Tbp disappeared in extremely short time after the injection. 1 min after the injection, fibrin fibers were seen between single sheet of membrane and endothelial cells of capillaries. In the rabbit which had died suddenly after the injection of T.Tbp, multiple pulmonary thrombi made of fibrin and platelets were seen in capillaries. The endothelial cells of capillaries were destroyed and interstitial tissues were edematous.The hypercoagulable state was seen 10~30sec after the start of the injection, indicating the shortening of r of TEG. Then, it gradually returned the level before injection. Moreover, changes of the measurements of fibrinogen, antiplasmin and prekallikrein were also seen after the injection.

Temperature Selection of Rainbow Trout (Salmo gairdneri) Fingerlings in Vertical and Horizontal Gradients

1971 ◽  
Vol 28 (11) ◽  
pp. 1801-1804 ◽  
Author(s):  
R. W. McCauley ◽  
W. L. Pond
Keyword(s):  
Rainbow Trout ◽  
Salmo Gairdneri ◽  
Temperature Preference ◽  
Temperature Selection ◽  
Horizontal Gradients ◽  
Significant Difference ◽  
Preferred Temperatures ◽  
Laboratory Investigations ◽  
Horizontal Temperature Gradients ◽  
Selection Of

Preferred temperatures of underyearling rainbow trout (Salmo gairdneri) were determined in both vertical and horizontal temperature gradients. No statistically significant difference was found between the preferred temperatures by the two different methods. This suggests that the nature of the gradient plays a lesser role than generally believed in laboratory investigations of temperature preference.

scholarly journals The Distribution of 35S-Sulfadiazine and 14G-Trimethoprim in Rainbow Trout, Salmo Gairdneri

1979 ◽  
Vol 20 (1) ◽  
pp. 25-37 ◽  
Author(s):  
Torill Bergsjø ◽  
Inger Nafstad ◽  
Kristian Ingebrigtsen
Keyword(s):  
Rainbow Trout ◽  
Salmo Gairdneri
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