First identification of Flavobacterium columnare infection in farmed freshwater striped catfish Pangasianodon hypophthalmus

Diseases of Aquatic Organisms

Tu Thanh Dung¹  Nguyen Thi Tien¹  Mags Crumlish¹  Nguyen Anh Tuan¹ 

关键词: Flavobacterium columnare;    White patch disease;    Pangasianodon hypophthalmus;   

DOI  :  10.3354/dao02478

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: The bacterium Flavobacterium columnare was recovered and identified as the aetiological agent causing freshwater columnaris infection in farmed striped catfish Pangasianodon hypophthalmus (Sauvage) fingerlings that had suffered high mortality rates within commercial hatchery ponds in Vietnam. The gross clinical signs were typical of columnaris-infected fish. Histological examination found numerous Gram-negative, filamentous bacteria present on the skin, muscle and gill tissues of affected fish. The yellow-pigmented bacteria were isolated and identified as F. columnare using primary, biochemical and PCR methods. An experimental immersion-challenge study with 2 strains was also performed. It fulfilled Koch’s postulates and showed a median lethal concentration (LC₅₀) of 4.27 × 10⁵ and 1.66 × 10⁶ cfu ml⁻¹ for the F. columnare strains FC-HN and FC-CT, respectively. To the best of our knowledge this is the first report of freshwater columnaris infection in P. hypophthalmus.

【 授权许可】

Unknown