牛蛙致病变形菌的鉴定及其敏感药物筛选

Identification and sensitive drug test of pathogenic Proteus vulgaris from Rana catesbeiana

摘要:

【目的】分离鉴定引起牛蛙(Rana catesbeiana)皮肤溃疡病症的致病菌，筛选抗菌药物。【方法】采用无菌解剖组织划线分离法分离致病菌，通过人工感染试验、菌体和菌落形态观察、API 20E系统鉴定、16S rRNA基因序列分析，确定分离菌的致病性及分类地位，并对该菌进行药物敏感性试验。【结果】从患病濒死牛蛙体内分离细菌NWG20141026，通过形态特征观察、生理生化试验、API 20E系统鉴定和16S rRNA基因序列相似性分析，认为NWG20141026菌株为普通变形菌(Proteus vulgaris)。人工感染试验显示，NWG20141026菌株不仅可以通过皮肤伤口感染引起蛙体表溃疡溃烂病症，也可通过消化道感染引起蛙肠炎病。药敏实验结果表明，氟苯尼考、四环素、多西环素、萘啶酸、磺胺异噁唑、恩诺沙星、红霉素等7种药物对普通变形菌具有较好的抑杀菌作用。【结论】引起牛蛙(R. catesbeiana)皮肤溃疡病症的致病菌NWG20141026为普通变形菌(P. vulgaris)，所患疾病命名为牛蛙变形菌病。普通变形菌对健康牛蛙具有较强致病性，氟苯尼考、四环素、多西环素、萘啶酸、磺胺异噁唑等5种药可作为防治牛蛙变形菌病的候选药物。

Abstract:

[Objective] Pathogen isolation, identification, and drug sensitivity test were performed on Rana catesbeiana that were suffering from skin ulcers in order to provide references to effectively prevent and control skin ulcers disease. [Methods] Pathogens, separated from the heart, liver and nidus of dying Rana catesbeiana infected by skin ulcers with the use of routine separation methods, were identified through artificial infection test, API 20E biochemical identification system, and 16S rRNA gene sequence analysis. Then, drug sensitivity test was conducted using paper diffusion method. [Results] One superior strain (NWG20141026), isolated from Rana catesbeiana infected by skin ulcers, exhibited strong pathogenicity to Rana catesbeiana by Artificial infection test. Through API 20E biochemical identification and 16S rRNA gene sequence analysis, it was found that the strain was Proteus vulgaris. The results from drug sensitivity test showed that phathogen of skin ulcer were highly sensitive to 7 medicines, such as florfenicol, tetracycline, doxycycline, nalidixic acid, sulfisoxazole, enrofloxacin, and erythrocin. [Conclusion] Skin ulcer disease, caused by Proteus vulgaris, could be treated by florfenicol, tetracycline, doxycycline, nalidixic acid, and sulfisoxazole.