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Bacterial Kidney Disease (bacterial + kidney_disease)
Selected AbstractsLack of uptake of Renibacterium salmoninarum by gill epithelia of rainbow troutJOURNAL OF FISH BIOLOGY, Issue 5 2000D. Mcintosh The role of rainbow trout (Oncorhynchus mykiss, Walbaum) gill cells in uptake of the salmonid pathogen Renibacterium salmoninarum was examined using in vitro, whole animal and isolated perfused head models. Uptake of the pathogen was observed only when dissected gill tissue was exposed to the live pathogen. In contrast, live cells of Yersinia ruckeri interacted with the gill epithelia in the isolated perfused head model, confirming the findings of previous studies with whole animal and in vitro systems. These results are discussed in relation to the role of gill tissue in bacterial kidney disease (BKD) pathogenesis and in antigen trapping. [source] Randomized clinical field trial of a bacterial kidney disease vaccine in Atlantic salmon, Salmo salar L.JOURNAL OF FISH DISEASES, Issue 7 2010T A Burnley Abstract A randomized, blinded clinical trial was performed to assess the relative effectiveness of five commercial and one experimental vaccine in a population of farmed fish experiencing a bacterial kidney disease (BKD) outbreak that occurred in one study cage that was part of a larger clinical field trial. A total of 6000 uniquely identified Atlantic salmon S1 presmolts were randomly assigned to vaccine groups in the hatchery and transferred to a commercial marine aquaculture site. Repeated sampling events to evaluate growth, inherent physical conditions and health status were carried out over the entire production cycle. During the second summer at sea, the study cage developed an outbreak of BKD that lasted approximately 240 days. The effectiveness of the selected vaccines was evaluated using survival analysis methods. The sole vaccine group offering protection for BKD was found to significantly decrease the hazard of dying (hazard ratio, HR = 0.68, P = 0.018) during the outbreak, compared to the industry standard, vaccine group. Additionally, during the outbreak, fish with a shortened operculum had a significantly decreased hazard (HR = 0.38, P = 0.033) compared to those fish with a normal operculum, while fish with jaw deformities had a significantly increased hazard (HR = 2.55, P = 0.001) compared to fish with normal jaw status. [source] A sensitive loop-mediated isothermal amplification (LAMP) method for detection of Renibacterium salmoninarum, causative agent of bacterial kidney disease in salmonidsJOURNAL OF FISH DISEASES, Issue 6 2009S K Gahlawat Abstract Loop-mediated isothermal amplification (LAMP) is a novel technique for nucleic acid amplification with high specificity, sensitivity and rapidity and does not require expensive equipment or reagents. In the present study, we developed and evaluated a LAMP method for the rapid detection of Renibacterium salmoninarum causing the bacterial kidney disease in salmonids. This method was more sensitive than quantitative real-time polymerase chain reaction (qPCR). Using DNA template extracted from cultured R. salmoninarum, the LAMP method gave an amplification signal from template diluted to 10,8 while the limit of detection of qPCR was10,7. The LAMP method was also highly specific and did not amplify DNA purified from five other Gram-positive and -negative bacterial fish pathogens. The method also worked well using extracts of macrophages infected with R. salmoninarum and kidney material from rainbow trout, which were positive for R. salmoninarum by qPCR and crude R. salmoninarum culture. There was some evidence for inhibitors of the LAMP reaction in the kidney samples, which was overcome by diluting the sample. [source] An immune-complex glomerulonephritis of Chinook salmon, Oncorhynchus tshawytscha (Walbaum)JOURNAL OF FISH DISEASES, Issue 12 2008J S Lumsden Abstract Chinook salmon from New Zealand were shown to have a generalized membranous glomerulonephritis that was most severe in large fish. Marked thickening of the glomerular basement membrane was the most consistent lesion, with the presence of an electron-dense deposit beneath the capillary endothelium. Severely affected glomeruli also had expansion of the mesangium and loss of capillaries, synechiae of the visceral and parietal epithelium and mild fibrosis of Bowman's capsule. Chinook salmon from British Columbia, Canada with bacterial kidney disease caused by Renibacterium salmoninarum had similar histological lesions. They also had thickened glomerular basement membranes that were recognized by rabbit antiserum to rainbow trout immunoglobulin. This was true only when frozen sections of kidney were used and not formalin-fixed tissue. An attempt to experimentally produce a glomerulopathy in rainbow trout by repeated immunization with killed R. salmoninarum was not successful. Case records from the Fish Pathology Laboratory at the University of Guelph over a 10-year period revealed that a range of species were diagnosed with glomerulopathies similar to those seen in Chinook salmon. The majority of these cases were determined to have chronic inflammatory disease. This report has identified the presence of immunoglobulin within thickened basement membranes of Chinook salmon with glomerulonephritis and supports the existence of type III hypersensitivity in fish. [source] Atypical growth of Renibacterium salmoninarum in subclinical infectionsJOURNAL OF FISH DISEASES, Issue 1 2006V Hirvelä-Koski Abstract Two growth types of Renibacterium salmoninarum were isolated from subclinically infected rainbow trout, one producing the smooth colonies typical of R. salmoninarum and the other forming a thin film on the surface of the agar with no separate colonies. The atypical growth was present on kidney disease medium agar in primary cultures of the kidney but not on selective kidney disease medium (SKDM). Fluorescent antibody staining of the fresh isolate and polymerase chain reaction amplification were the most reliable techniques to identify the atypical growth of R. salmoninarum. The condition was reversible, with growth reverting from atypical to the smooth colony form in experimentally infected rainbow trout and under laboratory conditions. There was no mortality, or any clinical signs of bacterial kidney disease (BKD) in the fish challenged with the atypical growth, although small numbers of smooth colonies of R. salmoninarum were isolated from 8% of these fish. The atypical growth reported here may explain some of the failures of culture, when SKDM agar alone is used for the detection of BKD in subclinically infected fish. [source] | ||||||||||