Pan-steatitis in farmed northern bluefin tuna, Thunnus thynnus (L.), in the eastern Adriatic.
Clinical, gross and histopathological investigations were carried out into large-scale mortalities on eastern Mediterranean bluefin tuna, Thunnus thynnus (L.), farms. Fish showed only nervous signs and darkened colour. At post-mortem the liver was bronze coloured and the pyloric area waxy in consistency. There was no evidence of any other gross pathology. Histopathology showed severe hepatic necrosis and lipidosis. Peri-pancreatic lipoid tissue was heavily infiltrated with an inflammatory round cell infiltrate. Fish on all three farms had been fed on a North African pilchard diet rather than traditional local or Baltic species. Once the diet was modified, losses ceased. A diagnosis of pan-steatitis as seen in other farmed fish species, as well as in terrestrial animals, on particular fish-based diets was made, although the actual factor within the diet which induced the inflammatory effect is not known.
Roberts
R J
RJ
Hagerman Fish Culture Experiment Station, University of Idaho, Hagerman, ID 83332, USA. heronpisces@btinternet.com
Agius
C
C
D000273:Adipose Tissue / Q000473:pathology; D000821:Animal Feed / Q000009:adverse effects*; D000818:Animals; D004032:Diet / Q000662:veterinary*; D005393:Fish Diseases / Q000209:etiology* / Q000503:physiopathology; D005398:Fisheries; D008099:Liver / Q000473:pathology; D008522:Mediterranean Sea; D013231:Steatitis / Q000209:etiology* / Q000503:physiopathology; D016896:Treatment Outcome; D014413:Tuna / Q000502:physiology*