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Relationship between resistance of salmonids to furunculosis and recovery of Aeromonas salmonicida from external mucus

R. C. Cipriano·L.A. Ford·T.E. Jones
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Abstract

Fish were sampled at the Ed Weed State Fish Hatchery (South Hero, Vermont, USA) in September 1992. Aeromonas salmonicida was common, with concentrations as high as 10 5 to 10 7 colony-forming units per gram of mucus, and readily recovered from most mucus samples obtained from furunculosis-sensitive populations of brook trout ( Salvelinus fontinalis ), lake trout ( Salvelinus namaycush ), and Atlantic salmon (Salmo salar) . The pathogen was the predominant microorganism and accounted for greater than 85% of the total number of bacteria isolated from the mucus of these fish. By comparison, A. salmonicida was recovered only from two rainbow trout ( Oncorhynchus mykiss ), and bacterial frequencies did not exceed 10 3 colony-forming units per gram of mucus. The pathogen was not recovered from the mucus of steelhead ( O. mykiss ) or Rome brown trout ( Salmo trutta ) selectively bred for resistance to furunculosis, even though there was widespread contagion throughout the hatchery and fish were cultured on a common, unprotected water supply.

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BibTeXRIS

R. C. Cipriano, L.A. Ford, T.E. Jones. 1994. Relationship between resistance of salmonids to furunculosis and recovery of Aeromonas salmonicida from external mucus. https://doi.org/10.7589/0090-3558-30.4.577

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