Francisella philomiragia, bacteria asociada con altas mortalidades en salmones del Atlántico (Salmo salar) cultivados en balsas-jaulas en el lago Llanquihue

Abstract

SuMMARyFrancisella philomiragia was isolated from Atlantic salmon cage-farmed in the Llanquihue lake with outbreaks of a granulomatous disease, with high rates of morbidity and an accumulated mortalities between 5% to 20%. The isolates had 100% similarity with F. philomiragia ssp noatunensis or F. piscicida isolated in Atlantic cod, 99% similarity with Francisella sp. detected in tilapia from Asia and Central America and 99% of similarity with the reference strain F. philomiragia through 16s rDNA phylogenetic analysis.Palabras clave: Francisella philomiragia, salmón del Atlántico, análisis filogenético.

Antimicrobial susceptibility of Francisella noatunensis subsp. noatunensis strains isolated from Atlantic cod Gadus morhua in Norway

“…These values are similar to the values found in the present study (Table 1). However, Bohle et al (2009) also reported a MIC value of 0.5 µg ml −1 for oxytetracycline, which is much lower than the value of 64 µg ml −1 found in our investi gation (Table 1). In a recent study, Soto et al (2012) present MIC values for 10 isolates of F. noatunensis subsp.…”

“…strains isolated from fish. Bohle et al (2009) reported MIC values of 0.25 µg ml −1 for flumequine and oxolinic acid and 1.0 µg ml −1 for florfenicol for F. philomiragia cultures isolated from infected Atlantic salmon Salmo salar. These values are similar to the values found in the present study (Table 1).…”

Francisella infections in farmed and wild aquatic organisms

“…Extensive chronic granulomatous inflammation with multiple granuloma in all organs is the main histopathological finding with few to numerous, small Gram-negative bacteria, sometimes observed within granuloma [7]. A granulomatous condition is also reported in association with Francisella infections in Atlantic salmon [1,43]. No granuloma were observed in association with the first report of Francisellosis in a non-vertebrate i.e.…”

“…The lack of granuloma formation in abalone may be more related to the molluscan immunological repertoire, rather than differences in the infecting bacterium. Reported mortalities associated with natural infections range from low level in striped bass [37], 5-20% in Atlantic salmon [43] to 95% in tilapia [33]. Francisellosis in cod is associated with varying mortality levels.…”

Chilean Salmon Farming on the Horizon of Sustainability: Review of the Development of a Highly Intensive Production, the ISA Crisis and Implemented Actions to Reconstruct a More Sustainable Aquaculture Industry

“…Subsequently, in June 2006 the gram-negative bacteria Francisella was confirmed as the agent responsible for UA2, which caused severe mortalities in Atlantic salmon farms located in Lake Llanquihue (Birkbeck et al, 2007). Francisella philomiragia presented high rates of morbidity and outbreaks with cumulative mortality ranging from 5% to 20% (Bohle et al, 2009). This bacterium presented 100% homology with F. philomirhagia subsp.…”