Polyphasic characterization of Aeromonas salmonicida isolates recovered from salmonid and non-salmonid fish
Michigan’s fisheries rely primarily upon the hatchery
propagation of salmonid fish for release in
public waters. One limitation on the success of
these efforts is the presence of bacterial pathogens,
including Aeromonas salmonicida, the causative
agent of furunculosis. This study was undertaken
to determine the prevalence of A. salmonicida in
Michigan fish, as well as to determine whether
biochemical or gene sequence variability exists
among Michigan isolates. A total of 2202 wild,
feral and hatchery-propagated fish from Michigan
were examined for the presence of A. salmonicida.
The examined fish included Chinook salmon,
Oncorhynchus tshawytscha (Walbaum), coho salmon,
O. kisutcha (Walbaum), steelhead trout, O. mykiss
(Walbaum), Atlantic salmon, Salmo salar L.,
brook trout, Salvelinus fontinalis (Mitchill), and
yellow perch, Perca flavescens (Mitchill). Among
these, 234 fish yielded a brown pigment-producing
bacterium that was presumptively identified as
A. salmonicida. Further phenotypic and phylogenetic
analyses identified representative isolates as
Aeromonas salmonicida subsp. salmonicida and
revealed some genetic and biochemical variability.
Logistic regression analyses showed that infection
prevalence varied according to fish species/strain,
year and gender, whereby Chinook salmon and
females had the highest infection prevalence.
Moreover, this pathogen was found in six fish species
from eight sites, demonstrating its widespread
nature within Michigan.
Keywords: Aeromonas salmonicida, bacteria, fish
disease, Great Lakes.
Auteur(s) : A Diamanka1, T P Loch1, R C Cipriano2 and M Faisal1,3
Pages : 949–963
Année de publication : 2013
Revue : Journal of Fish Diseases
N° de volume : 36
Type : Article
Mise en ligne par : DIAMANKA Arfang