致奶牛乳房炎大肠杆菌的分离鉴定及药敏试验

Isolation,Identification and Drug Resistance Test of Escherichia Coli. in Dairy Cow Mastitis

为查明新疆北疆地区某牛场奶牛乳房炎的主要病原菌,提供一套治疗方案,本实验以该场出现乳房炎症状的奶牛为研究对象,采用常规微生物学方法,进行细菌的分离鉴定及药敏实验。结果表明,引起奶牛乳房炎的致病菌为大肠杆菌,生理生化特性表明:M.R、吲哚反应变为红色为阳性;V-P与柠檬酸钠反应为阴性;三糖铁斜面能产气、产酸,不生成H2S;能发酵乳糖、葡萄糖、麦芽糖、棉子糖、山梨醇和甘露醇,一株可以分解蔗糖,另一株不能分解蔗糖。药敏试验结果表明,分离菌株对氨苄西林、头孢唑啉、氧氟沙星、恩诺沙星、克林霉素、庆大霉素、呋喃妥因敏感;对青霉素、阿莫西林、链霉素、四环素耐受。

In order to find out the main pathogens of dairy cow mastitis in a cattle farm in northern Xin jiang, a set of treatment plan was provided. In this experiment, the dairy cow with mastitis symptoms was used as the research object, and conventional microbiological methods were used to isolate and identify bac teria, and drug resistance test. The results showed that the pathogens causing dairy cow mastitis were Escherichia coli. The physiological and biochemical characteristics showed that the M. R and indole reac tions turns red to positive~ the VP and sodium citrate reaction was negative~ the trisaccharide iron could produce gas, acid and not generate H2S; and it can ferment lactose, glucose, maltose, raffinose, sorbitol and mannitol, one strain of bacteria can decompose sucrose ance test showed that the isolated strains were sensitive to elindamycin, gentamicin and nitrofurantoin, as well as this and the other not. The results of drug resist- ampicillin, cefazolin, ofloxacin, enrofloxacin, strains were tolerant to penicillin, amoxicillin,streptomycin and tetracycline.