Real-time PCR detection of Moritella viscosa, the likely causal agent of winter-ulcer in Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss

S Grove; L J Reitan; T Lunder; D Colquhoun

doi:10.3354/dao01972

Real-time PCR detection of Moritella viscosa, the likely causal agent of winter-ulcer in Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss

Dis Aquat Organ. 2008 Nov 20;82(2):105-9. doi: 10.3354/dao01972.

Authors

S Grove¹, L J Reitan, T Lunder, D Colquhoun

Affiliation

¹ National Veterinary Institute, PO Box 8156 Dep, 0033 Oslo, Norway. soren.grove@vetinst.no

PMID: 19149373
DOI: 10.3354/dao01972

Abstract

We report the development of a real-time PCR protocol for specific detection of Moritella viscosa. This bacterium is considered to be the main aetiological agent in development of winter-ulcer, a disease severely affecting salmonid aquaculture in Norway. From a newly elaborated draft version of the genome of M. viscosa, the tonB gene sequence was selected as a suitable basis for the development of the real-time PCR assay. The real-time PCR demonstrated the presence of M. viscosa DNA sequences in 88.1% of samples collected from 35 outbreaks of winter-ulcer in Norwegian fish farms. In contrast, standard culturing on blood agar identified M. viscosa in only 39.7% of fish. While the culturing method revealed a similar prevalence (26 to 27%) of M. viscosa in kidney and ulcer samples, substantially more ulcer (81.5%) than kidney (49.7%) samples were shown positive by real-time PCR.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bacteriological Techniques
Fish Diseases / microbiology*
Gram-Negative Bacterial Infections / microbiology
Gram-Negative Bacterial Infections / veterinary*
Moritella / isolation & purification*
Oncorhynchus mykiss*
Polymerase Chain Reaction / veterinary*
Salmo salar*
Sensitivity and Specificity