魚體常有細菌之研究—Ⅰ存在于外觀健康之鰻魚之鰓腸血液及內臟之細菌

Studies on the Bacterial Flora of Fish Body-Ⅰ. Bacterias in Gill, Intestine, Blood and Viscera of Apparently Healthy pond-cultured Eels

鍾虎云(Huu-Yun Chung) ； 郭光雄(Guang-Hsiung Kou)

《臺灣水產學會刊》 2卷2期 (1973/12) Pp. 20-25

https://doi.org/10.29822/JFST.197312.0004

摘要

自1972年8月起至1973年7月止，在本省桃園、羅東、鹿港、屏東等地區之養鰻場採集外觀健康之鰻魚，進行魚體鰓部、腸內、血液及內臟（肝臟及腎臟）之細菌分離得以下之結果：
(1)由108尾健康鰻共分離出390株菌，可分為Aeromonas，Pseudomonas，Enterobacteriaceae，Vibrio，Achromobacter-Alcaligenes，Flavobacterium及Unidentified Gram-negative rods等7個groups，而以Aeromonas，Pseudomonas及Enterobacteriaceae之出現率為最顯著。
(2)鰓、腸內、內臟（肝、腎）之細菌相皆為同一組成，故可推測細菌是經由鰓或腸而進入魚體內，同時此細菌相受外圍環境水域之細菌相所支配。
(3)由魚體內臟分離出細菌之鰻魚以分離出Aeromonas及Enterobacteriaceae之魚數目最多，Pseudomonas，Flavobacterium及Achromobacter-Alcaligenes次之，而以分出Unidentified Gramnegative rods者為最少，僅有2尾(1.85%)。內臟帶有細菌之魚數為45尾佔41.67%。
(4)分離菌102株菌中對泥鰍病原性試驗之結果為26株具有病原性，佔25.49%，其中以Aeromonas之20株(19.6%)佔絕大多數，Pseudomonas為2株(1.96%)，Enterobacteriaceae為4株(3.92%)。在各類供試菌中之比例則為Aeromonas 43.48%，Pseudomonas 14.29%，Enterobacteriaceae 15.38%，Flavobacterium，Achromobacter-Alcaligenes及Unidentified Gram-negative rods等3個groups中皆無病原性菌株出現。由此推斷進入魚體內之细菌除一般所謂淡水魚類病原菌Aeromonas之外，Pseudomonas及Enterobacteriaceae在魚體健康情況惡化時，開始繁殖並致使魚體生病之可能性亦很高。

並列摘要

A total of 108 apparently healthy eels were collected from eel ponds in Taoyuan, Roatung, Lukang and Pingtung for examination of the presence of aerobic bacteria. A total of 390cultures of bacteria were isolated from gills, intestines, blood and viscera of the fish. The isolated bacteria were classified into seven groups: Aeromonas, Pseudomonas, Enterobacteriaceae, Vibrio, Flavobacterium, Achromobacter-Alcaligenes and unidentified Gram-negative rods. Among these groups the occurrence of Aeromonas, Pseudomonas and Enterobacteriaceae were predominant.
The bacteria concerned appear to be water species, which invade the muscle and body cavity of the fish, as well as the gill and gut-content. The frequency of positive cases inviscera of apparently healthy eels was 45 out of a total number of 108, i.e. 41.67%. Insome cases, two or more bacteria groups were isolated from the same eel. The frequencies of bacteria in the viscera were as follow: Aeromonas 14.81%; Pseudomonas 9.26%; Flavobacterium11.11%; Enterobacteriaceae 13.89%; Achromobacter-Alcaligenes 5.56%; unidentified Gram-negative rods 1.85%.
According to the results of pathogenecity tests, the virulent strains were 26 out of a total of 102 strains examined, i .e. 25.49%. Most of the virulent strains were Aeromonas (20 strains).