牛蛙爱德华氏菌病病原菌的鉴定和致病因素的研究

从患爱德华氏菌病的牛蛙肌肉、肝、肾、血液和腹水中分离到8株细菌，根据其形态和生理生化特性鉴定为野生型迟钝爱德华氏菌。人工感染实验均为该病的病原菌，毒素检测试验表明，致病因素主要是内毒素而不是外毒素。分离菌株的主要特性为杆状、革兰氏阴性、周生鞭毛、兼性厌氧。接触酶、甲基红试验和硝酸盐还原均为阳性。在三糖铁琼脂上产H2S。氧化酶、丙二酸盐利用、V．P试验、明胶液化、尿素酶。苯丙氨酸脱氨酶为阴性。分解葡萄糖、甘露糖、麦芽糖，产酸产气，不利用甘露醇、蔗糖和阿拉伯糖。

Studies on the pathogencities and biologic characteristics of the pathogens causing the Edwardsiellosis of the bullfrog

This paper first describes Edwardsiellosis of the bullfog. Eight becterial strains were isolated from muscle, liver, kidney, blood and ascites of the diseased bullfrog.Infection experiments ascertained that the bacterial isolates were the cause of the disease, the toxin test showed the bacterium produced endotoxin instead of exotoxin. All of the isolates were Gram - negative rods with peritrichous flagella, and were characteristic of facultative anaerobiosis, catalase and methl red positive, and reduce nitrate to nitrite. They produced abundant hydrogen sulfide on TSI agar. Voges - proskauer,gelatin, urease and phenlalanine deaminase were negative. Acid and gas were produced by them from D - glucose, D - mannose and maltose. D - mannitol, Sucrose and L - Arabinose were not utilized. The strains were identified as Edwardsiella tarde wild type.