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Bacterial cold water disease (BCWD) is a bacterial disease of salmonid fish. It is caused by ''Flavobacterium psychrophilum'' (previously classified in the genus ''Cytophaga''), a gram-negative〔 rod-shaped bacterium of the family Flavobacteriaceae.〔Nematollahi, A., et al. (2003). (''Flavobacterium psychrophilum'' infections in salmonid fish. ) ''Journal of Fish Diseases'' 26(10), 563–74. doi 10.1046/j.1365-2761.2003.00488.x PMID 14653314〕 The disease typically occurs at temperatures below 13⁰C, and it can be seen in any area with water temperatures consistently below 15⁰C.〔 Salmon are the most commonly affected species. This disease is not zoonotic. Asymptomatic carrier fish and contaminated water provide reservoirs for disease. Transmission is mainly horizontal, but vertical transmission can also occur. BCWD may be referred to by a number of other names including cold water disease, peduncle disease, fit rot, tail rot and rainbow trout fry mortality syndrome. ==Diagnosis== Fish infected with typical BCWD have lesions on the skin and fins. Fins may appear dark, torn, split, ragged, frayed and may even be lost completely. Affected fish are often lethargic and stop feeding. Infection may spread systemically. Salmonid fish can also get a chronic form of BCWD〔 following recovery from typical BCWD. It is characterised by erratic “corkscrew” swimming, blackened tails and spinal deformities.〔 In rainbow trout fry syndrome, acute disease with high mortality rates occurs. Infected fish may show signs of lethargy, inappetance and exopthalmos before death. A presumptive diagnosis can be made based on the history, clinical signs, pattern of mortality and water temperature, especially if there is a history of the disease in the area. The organism can be cultured for definitive diagnosis. Alternatively, histology should show periostitis, osteitis, meningitis and ganglioneuritis.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Bacterial cold water disease」の詳細全文を読む スポンサード リンク
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