鱘魚病魚分離Staphylococcus lugdunensis之特性及病原性研究

Study on the characteristics and pathogenicity of Staphylococcus lugdunensis isolated from sturgeon, Acipenser schrencki

薛人華(Jen-Hua Hsueh)

指導教授 ： 張本恒

國立臺灣大學/獸醫專業學院/獸醫學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.00208

摘要

本研究首次在台灣從鱘魚 (Acipenser schrencki) 分離出Staphylococcus lugdunensis，自動物園飼養之鱘魚分離Staphylococcus lugdunensis 菌株進行病原性試驗，以人工皮膚割傷後，菌液浸泡幼魚，以8.1×108CFU/mL、1.95×109CFU/mL及1.95×109CFU/mL細菌濃度進行三組重複試驗，第14天累計死亡率分別為83.3％、66.6％及33.3％，顯示該菌對鱘魚之致病性較為慢性，死亡魚隻浮游水表面或沉於底部，魚體呈現彎曲狀，且體表色變淡並附著黏液，於鰓蓋底部、體腹表面及擦傷部位可見明顯潮紅及出血現象。分離株於形態學、生長特性和生理生化特性方面類似標準菌株S. lugdunesis。對大多數抗生素對具有感受性。以葡萄球菌16S rDNA引子，增幅出1320bp片段，與S. lugdunensis有99％相似度。再根據S. lugdunesis之外毒素hemolysin (slush) 基因設計，可增幅出1011bp之PCR片段，與S. lugdunensis hemolysin gene有99％相似度。本研究顯示出鱘魚引起出血敗血病變與S. lugdunensis之病原性具有關聯性，也證實出為台灣首度鱘魚感染S. lugdunensis病例。

關鍵字

鱘魚 ； Staphylococcus lugdunensis ； 葡萄球菌 ； 出血性敗血症

並列摘要

This study described the first isolation of Staphylococcus lugdunensis from sturgeon, Acipenser schrencki, in Taiwan. The pathogenicity experiments were performed by immersion challenge in juvenile sturgeons. Fish were received 8.1×108CFU/mL, 1.95×109CFU/mL and 1.95×109CFU/mL of bascterial suspension and triple duplicate, and the cumulative mortality was 83%, 66.6％and 33.3％, respectively. It revealed chronic pathogenicity of S. lugdunensis for sturgeons. During the necropsy, the body of dead fish appeared curved shape, discorolation and mucus secretion. The congestion and hemorrhage were present on the base of operculum, the surface of abdmenal skin, and the skin of scraping area. The growth character, morphology and biochemical properties of S. lugdunensis isolated from sturgeons were similar to the reference strain of S. lugdunensis. The 16S rDNA sequence of 1320bp amplicon from isolates has shown 99% identify with S. lugdunensis. The S. lugdunensis hemolysin (SLUSH) sequence of 1011bp amplicon also has shown 99% identify with S. lugdunensis hemolysin gene. The results of this study revealed pathologenicitic and hemorrhagic of S. lugdunensis in sturgeons. This was the first report of S. lugdunensis in sturgeon cases.

並列關鍵字

Sturgeon ； Staphylococcus lugdunensis ； Hemorragic septicema

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