一株尼罗罗非鱼致病性嗜水气单胞菌的 分离鉴定及药敏试验

从自然感染发病的尼罗罗非鱼肝脏和脑组织中分离出1 株细菌，经革兰氏染色镜检、生化鉴定和PCR 鉴定，确定为嗜水气单胞菌，命名为GD001，进一步采用药敏纸片法测定分离菌株对多种抗生素的敏感性，并用该菌 株接种健康尼罗罗非鱼，鉴定其致病力。结果发现，GD001 菌株对恩诺沙星、头孢噻吩、四环素和克莱霉素等抗生素 敏感，对链霉素轻度敏感，对卡那霉素和青霉素不敏感。从人工感染10 g 左右的健康罗非鱼发现，GD001 菌株具有很 强的致病力，试验鱼在感染后3~4 h内全部死亡，且患病症状与自然发病症状的鱼一致。

Isolation, identification and drug sensitivity test of pathogenic Aeromonas hydrophila from Oreochromis niloticus

In this study, we isolated a bacterial strain named GD001 from liver and brain of natural infection Oreochromis niloticus. By gram staining, biochemical test and PCR identification, it was confirmed Aeromonas hydrophila. The results of drug sensitivity test indicated that the isolated strain was sensitive to enrofloxacin, cephalothin, tetracycline, clarith, light sensitive to streptomycin, and resistant to kanamycin and penicillin. The GD001 was used to infect healthy O. niloticus about 10 g, all infected fish died in 3-4 hours and the symptoms of the infected fish were consistent with the natural diseased fish.