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Detection and quantification of Renibacterium salmoninarum DNA in salmonid tissues by real-time quantitative polymerase chain reaction analysis

D.M. Chase·D.G. Elliott·R.J. Pascho
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Abstract

Renibacterium salmoninarum is an important salmonid pathogen that is difficult to culture. We developed and assessed a real-time, quantitative, polymerase chain reaction (qPCR) assay for the detection and enumeration of R. salmoninarum. The qPCR is based on TaqMan technology and amplifies a 69-base pair (bp) region of the gene encoding the major soluble antigen (MSA) of R. salmoninarum. The qPCR assay consistently detected as few as 5 R. salmoninarum cells per reaction in kidney tissue. The specificity of the qPCR was confirmed by testing the DNA extracts from a panel of microorganisms that were either common fish pathogens or reported to cause false-positive reactions in the enzyme-linked immunosorbent assay (ELISA). Kidney samples from 38 juvenile Chinook salmon (Oncorhynchus tshawytscha) in a naturally infected population were examined by real-time qPCR, a nested PCR, and ELISA, and prevalences of R. salmoninarum detected were 71, 66, and 71%, respectively. The qPCR should be a valuable tool for evaluating the R. salmoninarum infection status of salmonids.

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D.M. Chase, D.G. Elliott, R.J. Pascho. 2006-07-01. Detection and quantification of Renibacterium salmoninarum DNA in salmonid tissues by real-time quantitative polymerase chain reaction analysis. https://doi.org/10.1177/104063870601800409

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