Record Display for the EPA National Library Catalog


Main Title Systemic Hexamitid (Protozoa: Diplomonadida) Infection in Seawater Pen-Reared Chinook Salmon 'Oncorhynchus tshawytscha'.
Author Kent, M. L. ; Ellis, J. ; Fournie, J. W. ; Dawe, S. C. ; Bagshaw, J. W. ;
CORP Author Environmental Research Lab., Gulf Breeze, FL. ;Department of Fisheries and Oceans, Nanaimo (British Columbia). Pacific Biological Station. ;Scanmar Seafood Ld., Sechelt (British Columbia).
Publisher c1992
Year Published 1992
Report Number EPA/600/J-93/069;
Stock Number PB93-169035
Additional Subjects Protozoan infections ; Fish diseases ; Salmon ; Mortality ; Ascites ; Kidney ; Hyperplasia ; Edema ; Inflammation ; Tissues(Biology) ; Reprints ; Hexamita salmonis ; Onchorhynchus tshawytscha
Library Call Number Additional Info Location Last
NTIS  PB93-169035 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 11p
A systemic infection with a hexamitid flagellate resembling Hexamita salmonis caused high mortality in chinook salmon Oncorhynchus tshawytscha reared at a seawater netpen farm in British Columbia, Canada. Affected fish were anemic and had swollen abdomens containing serosanguinous ascites and large blood clots. They also had an enlarged, mottled and congested liver, and an enlarged kidney and spleen. Numerous parasites were observed in the blood. The most remarkable histological changes were found in the liver and kidney. Livers of affected fish showed edema, congestion and inflammation. The renal interstitium was moderately hyperplastic due to proliferation of hemoblasts. The systemic infection was transmitted in the laboratory to chinook by intraperitoneal injection, by gavage of infected ascites and by waterborne exposure (in both fresh and sea water) with a mixture of infected ascites and tissue. The infection was also transmitted in fresh and sea water by cohabitation with infected chinook. Atlantic salmon were refractory to the infection. Based on the ease of transmission of the parasite in both fresh and sea water, and the high mortality associated with the infection, the disease poses a potentially serious threat to aquaculture of chinook salmon. (Copyright (c) Inter-Research 1992.)