The pathology of 'scale drop syndrome' in Asian seabass, Lates calcarifer Bloch, a first description.
J Fish Dis
; 35(1): 19-27, 2012 Jan.
Article
in En
| MEDLINE
| ID: mdl-22103767
ABSTRACT
This is the first pathological description of 'scale drop syndrome' (SDS) in Asian seabass, Lates calcarifer Bloch. Cumulative mortality was estimated at 40-50%. The vasculitis in all major organs including the skin and associated tissue necrosis was distinctive. The dermis overlying scale beds was often necrotic and associated with scale loss. Necrosis of splenic ellipsoids, renal glomeruli and choroid rete glands of eye were further hallmarks of a disease with systemic vascular involvement. The brain was not spared vascular damage, and the resulting multifocal encephalomalacia probably accounts for the spiral swimming behaviour in some affected fish. Other lesions included accentuated hepatic lobulation and gastric gland necrosis. Nuclear chromatin margination and karyolysis in hepatocytes, renal tubular epithelium and gastric and intestinal epithelium suggest specific targeting of cells. Basophilic cytoplasmic inclusions were present in spleen, kidney, liver, heart and choroid rete, but they were not prominent. Using transmission electron microscopy, two morphological forms of virions were observed single- and double-enveloped hexagonal virions. Based on size and morphology, these virions resemble iridovirus or herpesvirus. The cause of SDS is unknown, but the pathological changes, especially the vasculitis, suggest an infectious aetiology, possibly viral.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Bass
/
Fish Diseases
Limits:
Animals
Country/Region as subject:
Asia
Language:
En
Journal:
J Fish Dis
Journal subject:
BIOLOGIA
/
MEDICINA VETERINARIA
Year:
2012
Document type:
Article
Affiliation country:
Australia