RT Journal Article
T1 A Summer Mortality Outbreak of Lactococcosis by Lactococcus garvieae in a Raceway System Affecting Farmed Rainbow Trout (Oncorhynchus mykiss) and Brook Trout (Salvelinus fontinalis)
A1 Pastorino, Paolo
A1 Vela Alonso, Ana Isabel
A1 Colussi, Silvia
A1 Cavazza, Giulia
A1 Menconi, Vasco
A1 Mugetti, Davide
A1 Righetti, Marzia
A1 Barbero, Raffaella
A1 Zuccaro, Gaetano
A1 Dondo, Alessandro
A1 Acutis, Pier Luigi
A1 Prearo, Marino
A1 Fernández-Garayzábal Fernández, José Francisco
AB Lactococcosis is a fish disease of major concern in Mediterranean countries caused by Lactococcus garvieae. The most susceptible species is the rainbow trout (Oncorhynchus mykiss), suffering acute disease associated with elevated mortalities compared to other fish species. References reported that other salmonids are also susceptible to the disease, but no mortality outbreak has been described to date. The aim of this study was to present a mortality outbreak that occurred in brook trout (Salvelinus fontinalis) farmed in northwestern Italy during the summer of 2018. Fish exhibited clinical signs, such as exophthalmos, diffused hemorrhages localized in the ocular zone, hemorrhagic enteritis, and enlarged spleen. L. garvieae was isolated in all fish. Molecular and epidemiological characterization of the isolates, through Pulsed Field Gel Electrophoresis (PFGE), confirmed the initial hypothesis of water as vehicle of infection favoring transmission between rainbow trout farmed in upstream compartments and brook trout located in downstream tanks. Moreover, several environmental conditions affected and promoted the outbreak, among them the high-water temperature, which probably induced a physiological stress in brook trout, being way above the optimal temperature for this species, increasing the susceptibility to infection.
PB MDPI
SN 2076-2615
YR 2019
FD 2019-11-29
LK https://hdl.handle.net/20.500.14352/7923
UL https://hdl.handle.net/20.500.14352/7923
LA eng
NO Ministerio de Ciencia e Innovación (MICINN)
DS Docta Complutense
RD 8 abr 2025