大口鲶病原菌蛭弧菌的分离及其生物学特性研究

Isolation of Bdellovibrio Infacting Silurus meridionalis Pathogens and Its Biological Characteristics

从患病南方大口鲶分离得到病原菌N1、N2、N3、N4,以N3为宿主菌,从鱼塘淤泥中分离到三株蛭弧菌。其中蛭弧菌Bd-tw7的宿主菌范围广泛,不仅能降解嗜水气单胞菌、N1、N2、N3、N4等鱼类病原菌,而且能降解大肠杆菌C600、金黄色葡萄球菌等细菌。其在1/10NB双层琼脂平板上形成圆形透明的噬菌斑,最适温度35℃,最适pH为7.5,短杆状,单极生鞭毛。在水体防病试验中,试验组的鱼存活率明显高于对照组(P<0.05)。

The pathogenic strains were isolated from sick Silurus meridionalis, named N1, N2, N3 and N4. And three Bdellovibrios were isolated from fishpond sullage using N3 as prey. The host range of Bdellovibrios Bd - tw7 was very wide. It no only can lyse the pathogenic strains Aeromonas hydrophila, N1, N2, N3 and N4, but also E. coli C600 and Staphylococcus aureus. The plaque of Bdellovibrios Bd - tw7 is round and clear on 1/10 NB double - layer agar medium. Its optimal temperature was 35 ℃ , the optimal pH was 7.5 , Its form was short rod and had one long flagellum on one end of the cell. With Bdellovibrios Bd -tw7 added into water , the survival rate of tested group was higher than normal control group （P〈0. 05）.