Sequence data from salmonid alphavirus (SAV) strains obtained from farmed marine Atlantic salmon, Salmo salar L. , over a 20‐year period between 1991 and 2011 was reviewed to examine the geographical distribution of the genetically defined SAV subtypes in twelve regions across Ireland and Scotland. Of 160 different Atlantic salmon SAV strains examined, 62 belonged to subtype 1, 28 to subtype 2, 34 to subtype 4, 35 to subtype 5...

A comparative challenge study of six marine isolates representing subtypes 1–6 of salmonid alphavirus ( salmon pancreas disease virus , Genus Alphavirus , Family Togaviridae ) was conducted in Atlantic salmon in a fresh water cohabitation trial. Histopathological lesions typical of pancreas disease were observed with all subtypes, and virus was re‐isolated from serum of cohabitant fish in each case. Using a virus neutralizatio...

A simple method of detecting the presence of the salmonid alphaviruses (SAVs), salmon pancreas disease virus (SPDV) and sleeping disease virus (SDV), from serum samples is described. Using a 96‐well tissue‐culture plate format, test sera are diluted in medium and added to chinook salmon embryo (CHSE‐214) cells. After incubation for 3 days at 15 °C, plates are fixed and stained using a monoclonal antibody (mAb)‐based immunopero...

Breeding systems vary widely in birds, from monogamous pairs through to complex group systems where subordinates assist breeding individuals to rear young each season. The Australian magpie varies geographically both in plumage patterns and social organization. Some populations of both eastern and western plumage forms are plural breeders with group size varying from three to over 15 mature individuals. This study used variati...

An annual disease problem with high levels of mortality in Atlantic salmon, Salmo salar L., on a freshwater farm was investigated. In 2000, mortalities began early in October and peaked in December, being unevenly distributed between tanks. Histopathological changes included severe hyperplasia of gill epithelium, with fusion of secondary lamellae, and extensive necrosis of the haematopoietic centres in the kidney and spleen, t...

Pancreas disease (PD) is a serious disease of farmed Atlantic salmon, Salmo salar L . It was first described in Scotland in 1976 and has subsequently been found in Ireland, Norway and North America. The disease primarily affects Atlantic salmon smolts during their first year at sea and losses can be as high as 50% of the yearly smolt input, but more recently it has become more common in one sea winter fish. Although there have...