Vertebral column deformity with curved cross‐stitch vertebrae in Norwegian seawater‐farmed Atlantic salmon, Salmo salar L

Pathological changes in the vertebral column of farmed Atlantic salmon in Norway have been reported since the 1990s. Based on the characteristic radiographic findings, we here present a vertebral column deformity named “curved cross‐stitch vertebrae” that mainly affects the middle aspect of the vert...

Full description

Saved in:
Bibliographic Details
Published in:Journal of fish diseases 2020-03, Vol.43 (3), p.379-389
Main Authors: Trangerud, Cathrine, Bjørgen, Håvard, Koppang, Erling Olaf, Grøntvedt, Randi Nygaard, Skogmo, Hege Kippenes, Ottesen, Nina, Kvellestad, Agnar
Format: Article
Language:English
Subjects:
Chemical analysis
Computed tomography
Fish
Freshwater fishes
gas
Histology
Malformations
Marine fishes
Necropsy
Notochord
Perforation
Radiography
Salmo salar
Salmon
Seawater
spinal deformity
Tomography
Vertebra
Vertebrae
Water analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Pathological changes in the vertebral column of farmed Atlantic salmon in Norway have been reported since the 1990s. Based on the characteristic radiographic findings, we here present a vertebral column deformity named “curved cross‐stitch vertebrae” that mainly affects the middle aspect of the vertebral column. Sixty fish, from the west/northwest coast of mid‐Norway, were sampled at slaughter and examined by radiography, computed tomography (CT), necropsy, macrophotography, and histology. The vertebral deformities were radiographically graded as mild, moderate, or marked. The main differences between these grades of changes were defined by increased curving of the peripheries of endplates, reduced intervertebral spaces, and vertical displacement of the vertebrae. The curved rims of endplates were located peripheral to a continuous and approximately circular borderline. The CT studies revealed small, multifocal, hypo‐attenuating, round to crescent‐shaped areas in the notochord, compatible with the presence of gas. Additionally, histology revealed that the axial parts of endplates had circular zones with perforations, through which either notochordal tissue prolapsed into the vertebrae or vascularized fibrochondroid proliferations extended from the vertebrae into the notochord. Inflammation was present in many vertebral bodies. To the best of our knowledge, this is the first report of gas in the notochord of fish.
ISSN:0140-7775
1365-2761
DOI:10.1111/jfd.13136