鲟鱼疑似肠炎病病原菌快速分离鉴定与药敏试验

Suspected sturgeon enteritis pathogen isolation and identification and medicine sensitivity test

对2尾患病杂交鲟体表、鳃、心、脾、肝、肠及肌肉病变进行观察,见病鱼体表粘液丰富,剖检见内脏出血、充血,肝脏坏死呈腐乳状,初诊为细菌性肠炎。取病鱼心、肝、脾、鳃、肠及肌肉分别同时接种于营养琼脂和普通肉汤培养基,培养后经革兰氏染色、氧化型与发酵型试验、氧化酶试验等初步鉴定。结果显示病灶处致病菌多为肠杆菌科细菌,仅一条鱼鳃部为弧菌科细菌。按肠杆菌科和弧菌科细菌的生化特性进行针对性生化试验。鉴定得5株细菌,分别是鲶鱼爱德华氏菌(Edwardsiella ictaluri)、猪霍乱沙门氏菌(Salmonella enterica)2株、发光致病杆菌(Photorhabdus luminescens)和霍乱弧菌(Vibrio cholerae)。药敏试验表明头孢噻肟对各菌株有很强的抑制作用,环丙沙星和四环素抑制作用较强,复方新诺明抑制作用最弱。

For two moribund sturgeon the following organs:skin,gills and the heart,spleen,liver,intestinal and muscle tissue lesions were observed,necropsy was carried out to observe the internal organs for suspected bleed congestion and it was found that the hepatic necrosis were curdle,which was considered to be the signed of bacterial enteritis disorders.Then for bacteria separation identification,the following organ:the heart,liver,spleen,gill,intestinal tissue,muscle and intestinal content respectively was vaccinated with nutrient agar and nutrient broth medium during training hours.After that the resulting test such as Gram s stains test,oxidation type and ferment type test,oxidation enzyme test was conducted for preliminary bacterial identification.Furthermore,according to preliminary identification results was used only for corresponding of biochemical identification and drug sensitivity test.The consequences of identification revealed that most of the organs were hit by Enterobacteriaceae bacteria,but in contrast only sturgeon gill was affected by Vibrionaceae bacteria.Depending on preliminary results of Vibrionaceae bacteria and Enterobacteriaceae bacteria biochemical characteristics were more detailed biochemical experiments.Total 5 strains bacteria were certified,Edwardsiella ictaluri,2 strains Salmonella enterica,Photorhabdus luminescens and Vibrio cholerae.The drug sensitivity test showed that cefotaxime had a strong inhibitory effect on all strains of bacteria,while ciprofloxacin and tetracycline had stronger inhibition effect,and the inhibitory effect of compound sulfamethazine was the lowest.