研究1992年至1996年間養殖吳郭魚之流行性病害,典型的病害特徵包括在各組織器官中形成多發性白色結或肉芽腫,病變以脾臟及前腎最嚴重,從罹病魚可以分離出革蘭氏陽性球菌,依據細菌之形態學、生物學及生物化學等特質,將細菌鑑定為表皮葡萄球菌Staphylococcus epidermidis,病原性試驗係以分離菌株LK0728 S. epidermidis進行,試驗魚之組織病變包含肉芽腫病變、組織傷及出現高電子密度顆粒等,病變發生情形均與自然罹病之吳郭魚很類似,本文係為第一篇吳郭魚遭受表皮葡萄球Staphylococcusepidermidis 侵害的病害報告。
This paper describes the epizootiology of a disease of tilapia with clinical signs that include white nodules and microscopic granulomatous formations. Diseased fish showed splenomegaly with diffusion of numerous white nodules. The most severe lesions were presented in the spleen and anterior kidney. Morphological, biological, and biochemical characteristics of microorganisms isolated from the diseased tilapia were examined and classified by Baird-Parker’s biochemical subgrouping scheme. Strain LK0728 identified as Staphylococcus epidermidis, was used in a challenge test. Histopathological changes were similar to those seen in naturally infected fish. This is the 1st report on the isolation of staphylococci pathogenic to tilapia and on the confirms the etiological agent causing mass mortality in tilapia from 1992 to 1996 in Taiwan.