淡水魚類病原菌Aeromonas liquefaciens之出現及其病原株與非病原株之生化學特性的研究

Studies on the Occurrence and Biochemical Properties of Virulent and Avirulent Strains of Freshwater Fish Pathogen, Aeromonas liquefaciens

郭光雄(Guang-Hsiung Kou)

《臺灣水產學會刊》 1卷2期 (1972/09) Pp. 8-13

https://doi.org/10.29822/JFST.197209.0002

摘要

1．由1966年2月起至1970年7月止，在日本各地之養殖場採集鰻魚、鯉魚、金魚及香魚等四種魚之健康魚與病魚以及養殖池水中分離出A. liquefaciens計339株，依據對泥鰍之病原性分為病原株、準病原株及非病原株。
2．病原株之出現率雖因魚種、地域、時期有所差異，一般上在健康魚為0～16.7%（平均11.5%），呈現本菌感染症狀之病魚者為53.8～100%（平均84.8%），呈現本菌感染症以外症狀之病魚者為14.8～37.2%（平均29.6%），養殖池水者為5.1～16.6%（平均6.9%）。各內臟中腎臟之病原株出現率為最高。
3．病原株107株中有102株(95.3%)為VP陽性，氣體產生株；VP陰性23株中僅有3株(13.0%)是病原株，氣體非產生性16株中僅1株(6.3%)是病原株，這些結果與過去的研究結果相符合。
4．除了VP反應，氣體產生性與病原性之相關性在本研究中再度被確認外，發現病原性與gelatin液化性，Litmus milk分解性，Arabinose分解性等之强弱有密切的關係。
5．由本研究結果可推想病原性之强弱、有無均與蛋白質分解酵素之種類或菌本身具有之酵素之量有密切的關係。

並列摘要

1. 339 strains of Aeromonas liquefaciens have been isolated from eel, carp, goldfish, ayu and fish pond water samples in various parts of Japan from February 1966 to July 1970. According to the results of loach pathogenicity, they were divided into virulent, attenuated virulent and avirulent strains.
2. Although the occurrence ratio of virulent strains varied according to the kinds of fishes, date of collections and locations of collections, that in diseased fish with Aeromonas infected symptoms was 53.8-100% (average 84.8%); in diseased fish without Aeromonas infected symptoms, 14.8-37.2% (average 29.6%); in healthy fish,0-16.7% (average 11.5%); and in pond water, 5.1-16.6% (average 6.9%). Among the diseased fishes, the highest occurrence ratio of virulent strains was in the kidney.
3. The results showed that 102 out of 107 virulent strains were VP positive and gas produced strains, 3 out of 23 VP negative strains were virulent strains and 1 out of 16 gas non-produced strains was virulent strains. This was in good agreement with those data given by Eddy and Schubert.
4. Pathogenicity was found closely related to the VP reation, production of gas, hydrolysis of gelatin, peptonization of litmus milk and utilization of arabinose.
5. On the results of the present studies, it could be assumed that pathogenicity of the present organism was closely related to the kinds and quantity of proteolytic enzymes.