Salmon Bacteria 

Microbial pathogens of pen-reared salmon in tissue smears, imprints stained or histological sections from kidneys. Bar = 10 µm. a) kidney section of Chinook salmon with BKD stained with Periodic acid-Schiff (PAS). Note the PAS-positive (red) bacteria in phagocytes in the kidney interstitium. b) Renibacterium salmoniarum, Gram. c) Vibrio anguillarum, Gram. d) Aeromonas salmonicida, Gram.. e) rosette agent, Gram. f) rosette agent, Giemsa. (Download full resolution TIFF image, 4.0 megabytes)

  Coho salmon liver with Piscirickettsia salmonis. Note white lesions in liver. This intracellular pathogen is a serious problem in pen-reared salmon in Chile, and has occasionally caused disease in British Columbia farms. It has also been detected in California. (Download full resolution TIFF image, 6.3 megabytes)

  Intracellular Piscirickettisia salmonis cells (green) in cell culture.
(Download full resolution TIFF image, 0.2 megabytes)

  Bacterial kidney disease, caused by Renibacterium salmoninarum. Note white lesions in swollen kidney and swollen spleen. This chronic bacterial infection is one of the most important diseases of wild and cultured salmonids, particularly in the Pacific Northwest. The infection is spread through infected eggs, and thus is difficult to control. (Download full resolution TIFF image, 0.6 megabytes)

  Coldwater disease in Coho salmon presmolts, caused by Flavobacterium psychrophilum. This bacterium causes erosion of the fins and skin. In severe cases, fins are completely destroyed and lesions may extend deep into the muscle. B. Scanning electron micrograph showing massive numbers of bacteria in lesions (x). (Download full resolution TIFF image, 1.0 megabytes)