title: Selective precipitation reaction: a novel diagnostic test for tissue pathology in Atlantic salmon, Salmo salar, infected with salmonid alphavirus (SAV3).
abstract: While investigating biomarkers for infection with salmonid alphavirus (SAV), the cause of pancreas disease (PD), a selective precipitation reaction (SPR) has been discovered in serum which could be an on-farm qualitative test and an in-laboratory quantitative assay for health assessments in aquaculture. Mixing serum from Atlantic salmon, Salmo salar, with SAV infection with a sodium acetate buffer caused a visible precipitation which does not occur with serum from healthy salmon. Proteomic examination of the precipitate has revealed that the components are a mix of muscle proteins, for example enolase and aldolase, along with serum protein such as serotransferrin and complement C9. The assay has been optimized for molarity, pH, temperature and wavelength so that the precipitation can be measured as the change in optical density at 340 nm (Δ340). Application of the SPR assay to serum samples from a cohabitation trial of SAV infection in salmon showed that the Δ340in infected fish rose from undetectable to a maximum at 6 weeks post-infection correlating with histopathological score of pancreas, heart and muscle damage. This test may have a valuable role to play in the diagnostic evaluation of stock health in salmon.
authors.affiliation: Institute of Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.
authors.forename: M
authors.initials: M
authors.lastname: Braceland
authors.affiliation: BioMar Ltd., Grangemouth, UK.
authors.forename: J
authors.initials: J
authors.lastname: Tinsley
authors.affiliation: Marine Harvest Scotland, Fort William, UK.
authors.forename: D
authors.initials: D
authors.lastname: Cockerill
authors.affiliation: BioMar Ltd., Grangemouth, UK.
authors.forename: R
authors.initials: R
authors.lastname: Bickerdike
authors.affiliation: Fish Vet Group, Inverness, UK.
authors.forename: M F
authors.initials: MF
authors.lastname: McLoughlin
authors.affiliation: Institute of Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.
authors.forename: P D
authors.initials: PD
authors.lastname: Eckersall
mesh_terms: D000524:Alphavirus / Q000502:physiology*; D018354:Alphavirus Infections / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary* / Q000821:virology; D000818:Animals; D017756:Aquaculture; D003955:Diagnostic Tests, Routine / Q000662:veterinary*; D005393:Fish Diseases / Q000175:diagnosis* / Q000473:pathology / Q000821:virology; D010182:Pancreatic Diseases / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary* / Q000821:virology; D040901:Proteomics; D020317:Salmo salar
keywords: blood; diagnostics; pathology; protein precipitation; salmon; virus infection