Prevalence of viral RNA from piscine reovirus and piscine myocarditis virus in Atlantic salmon, Salmo salar L., broodfish and progeny

摘要

Heart and skeletal muscle in?ammation (HSMI) is a disease that generally affects Atlantic salmon, Salmo salar L., of approximately 1 kg some months after sea transfer. The mortality is commonly medium to low (may be up to 20%), but the morbidity is high as most of the ?sh in the affected cages display histopathological changes in the heart (Kongtorp, Kjerstad, Taksdal, Guttvik & Falk 2004). It took over 10 years from when the disease was ?rst described until a particular virus was associated with the disease. In 2010, piscine reovirus (PRV) was identi?ed in ?sh from an outbreak of HSMI as well as in experimentally challenged ?sh (Palacios, Lovoll, Tengs, Hornig, Hutchison, Hui, Kongtorp, Savji, Bussetti, Solovyov, Kristoffersen, Celone, Street, Trifonov, Hirschberg, Rabadan, Egholm, Rimstad & Lipkin 2010). The virus is ubiquitous, but the viral load is signi?cantly elevated during an HSMI outbreak (Palacios et al. 2010). Surviving ?sh from an outbreak of HSMI will typically recover, but seem to be lifelong carriers of PRV.