scholarly journals Stress caused by social interaction and its effect on susceptibility to Aeromonas hydrophila infection in rainbow trout Salmo gairdneri

1988 ◽  
Vol 4 ◽  
pp. 83-89 ◽  
Author(s):  
G Peters ◽  
M Faisal ◽  
T Lang ◽  
I Ahmed
1979 ◽  
Vol 36 (10) ◽  
pp. 1174-1179 ◽  
Author(s):  
T. J. Trust ◽  
L. M. Bull ◽  
B. R. Currie ◽  
J. T. Buckley

Grass carp (Ctenopharyngodon idella), bred in Arkansas and maintained in British Columbia under defined culture conditions on pelleted diets and on aquatic weeds, were examined to determine their commensal gastrointestinal bacterial flora. Using anaerobic incubation, the total bacterial numbers cultured ranged from 6 × 104 to 4 × 108 (average 4 × 106) per g of alimentary tract plus contents. Obligately anaerobic bacteria were isolated and identified as species of Actinomyces, Bacteroides, Eubacterium, Fusobacterium, and Peptostreptococcus. This is the first description of the presence of these strictly anaerobic organisms in the gastrointestinal tract of fish. Indeed, many of the anaerobes isolated did not conform to previously described species. Members of the Genus Clostridium were also isolated by enrichment culture and appeared to be associated with a pond weed diet. A wide variety of facultative anaerobic bacteria were also isolated, with Aeromonas hydrophila predominating. The gastrointestinal tracts of goldfish (Carassius auratus) were also found to contain sizable numbers of obligate anaerobes, but the gastrointestinal tracts of hatchery-cultured rainbow trout (Salmo gairdneri) contained insignificant numbers. Key words: grass carp, anaerobic bacteria, gastrointestinal microflora, Aeromonas hydrophila, rainbow trout, goldfish


1966 ◽  
Vol 23 (12) ◽  
pp. 1957-1963 ◽  
Author(s):  
George Post

Rainbow trout serum was shown to be made up of three major protein components. These three major components did not coincide by electrophoretic mobility or by relative salt solubility with the classic albumin, α-, β-, and γ-globulin separation of the sera of higher animals. A component equivalent to γ-globulin of higher animals was found to be completely lacking in the sera of both immunized and non-immunized rainbow trout.Specific humoral antibodies in rainbow trout immune sera were found to be contained in the electrophoretically least mobile proteins. These proteins coincided most nearly to the β-globulins and possibly the least electrophoretically mobile α-globulins of higher animals. Salt solubility of the serum proteins containing the specific antibody assisted in this conclusion. The electrophoretically least mobile major serum protein components were found to contain all of the antibody activity. These proteins could be removed from immune serum by 20% sodium sulfate. The assumption was made that Aeromonas hydrophila antibodies in immunized rainbow trout blood serum may be made up of a complex of serum proteins with a broad range of salt solubility and electrophoretic mobilities.Serum proteins of rainbow trout could also be classified as euglobulins or pseudoglobulins. The serum proteins which contained the A. hydrophila antibodies were found to be euglobulins.


1966 ◽  
Vol 23 (10) ◽  
pp. 1487-1494 ◽  
Author(s):  
George Post

Rainbow trout (Salmo gairdneri) produced antibodies specific for Aeromonas hydrophila. Two parenteral routes yielded no measurable difference in rate of antibody synthesis. Method of bacterin suspension indicated adjuvant suspension was superior in maintenance of humoral antibody and challenge protection when compared to saline suspension of the organism.Antibody synthesis from adjuvant-suspended bacterin lagged approximately 30 days behind the rate of synthesis by fish receiving saline suspended bacteria. The highest measurable antibody titer reached by an individual was 1:64. Individuals receiving saline suspended bacterin showed evidence of loss of titer approximately 2 months after the last antigen inoculation. Definite decrease in titer was noted 5 months after the last antigen inoculation and the return to a probable nonimmune class by approximately one-half of the individuals 7 months after the last inoculation. All individuals receiving adjuvant-suspended bacterin remained in the probable immune class for as long as 6 months following the last bacterin inoculation, but only approximately one-half of the individuals remained in the probable immune class 7 months postinoculation.All fish receiving a weighed quantity of killed A. hydrophila orally each day for 9 consecutive months showed presence of humoral A. hydrophila antibody. This immunization procedure produced 50% of the individuals with humoral antibody titers considered to be in the probable immune class.Fish receiving no immunization remained with negative antibody titers throughout the experimental period.Definite protection was given fish which had been immunized by parenteral inoculation.Similar protection was given after immunization by either intramuscular or intraperitoneal routes. Fish receiving either saline or adjuvant-suspended bacterin parenterally showed analogous protection when challenged by the specific bacteria. Fish receiving oral bacterin received questionable protection against parenteral challenge of the specific organism.Phagocytosis was found to occur to a greater extent in immunized rainbow trout than in nonimmunized rainbow trout. An average phagocytic index of parenterally immunized rainbow trout was 1.08. Nonimmunized rainbow trout of the same age and egg source had an average phagocytic index of 0.30. The opsonic index was 3.6.


1981 ◽  
Vol 27 (10) ◽  
pp. 1114-1122 ◽  
Author(s):  
Brenda J. Allan ◽  
Roselynn M. W. Stevenson

Aeromonas hydrophila NRC 505 produced extracellular substances which were capable of causing pathological effects when injected into trout. Proteolytic activity and haemolytic activity of the extracellular products, and the effect on fish, were lost on heating. The extracellular substances from strain G35, a protease-deficient mutant, were significantly more toxic to both rainbow trout (Salmo gairdneri) and speckled trout (Salvelinus fontinalis) than the analogous preparation from the parental strain NRC 505. The response of speckled trout injected intraperitoneally with dilutions of the extracellular preparations implicates haemolytic activity as a significant lethality factor.


1971 ◽  
Vol 28 (11) ◽  
pp. 1801-1804 ◽  
Author(s):  
R. W. McCauley ◽  
W. L. Pond

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.


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

Sign in / Sign up

Export Citation Format

Share Document