SURVEY OF SALMONID PATHOGENS IN OCEAN-CAUGHT FISHES IN BRITISH-COLUMBIA, CANADA

A survey of wild fishes captured around marine net-pen salmon farms an d from open waters for certain salmonid pathogens was conducted in the coastal waters of British Columbia. Viral hemorrhagic septicemia viru s was detected in Pacific herring Clupea pallasi, shiner perch Cymatog aster aggregata, and threespine sticklebacks Gasterosteus aculeatus. I nfectious hematopoietic necrosis (IHN) virus was detected in one Pacif ic herring (collected well away from the farms) and in tube-snouts Aul orhynchus flavidus and shiner perch collected from a farm experiencing an IHN outbreak. Renibacterium salmoninarum was observed in moribund Pacific hakes Merluccius products collected from within a net-pen and was also detected in several ocean-caught salmon. Aeromonas salmonicid a subsp. salmonicida (typical strain) was isolated from a juvenile chi nook salmon Oncorhynchus tshawytscha, whereas the atypical strain of t his organism was isolated from a lingcod Ophiodon elongatus. Loma salm onae (Microsporea) was observed in chinook salmon, chum salmon Oncorhy nchus keta, coho salmon O. kisutch, sockeye salmon O. nerka, and pink salmon O. gorbuscha, all of which were captured well away from net-pen s. Loma spp. (Microsporea) were observed in the gills of shiner perch, lingcod, Pacific tomcod Microgadus proximus, Pacific cod Gadus macroc ephalus, walleye pollock Theragra chalcogramma, and sablefish Anoplopo ma fimbria; all but the first species represent new hosts for Loma. Ep itheliocystis, caused by a chlamydia-like organism, was detected in th e gills of chinook salmon, chum salmon, coho salmon, pink salmon, ling cod, Pacific cod, Pacific hakes, Pacific tomcod, walleye pollock, sabl efish, shiner perch, Dover soles Microstomus pacificus, Pacific sandda bs Citharichthys sordidus, and various species of rockfish Sebastes sp p., most of which represent new host records for this infection.