奶牛乳房炎病原菌分离鉴定及耐药性试验.doc

奶牛乳房炎病原菌的分离鉴定及耐药性试验 摘要：为查清伊利合肥牧场奶牛乳房炎的主要病原菌种类、分布情况以及病原菌的耐药情况，并为奶牛乳房炎的综合防治提供依据，对本场采集的20份临床型乳房炎奶样进行细菌分离鉴定，并对主要病原菌进行药敏试验。共分离到13株细菌，结果金黄色葡萄球菌6株、表皮葡萄球菌2株、无乳链球菌1株、大肠杆菌3株、铜绿假单胞菌1株。在所选用的11种常用药物中，新霉素、乙酰螺旋霉素、壮观霉素、强力霉素对所分离的病原菌都有较好的杀灭作用，庆大霉素、红霉素、氯霉素、卡那霉素对革兰氏阳性菌的杀菌效果较好，而对革兰氏阴性菌不敏感。常用药物如青霉素、链霉素、磺胺类药物的抑菌效果不明显，大多菌株已产生耐药性。 关键词：奶牛乳房炎；病原菌；分离鉴定；药敏试验Isolation and Identification of Pathogenic Bacteria Causing Dairy Cattle Mastitis and Drug Sensitivity Test Student majoring in veterinary Zhang Sai Tutor Ren Baobo Abstract: To indagate the species and distributing of the main pathogetic bacteria causing dairy cow mastitis in Yili Cattle Farm in Hefei, identify the susceptivity to antibiotic of mail pathogens , and to provide a theory evidence for comprehensive prevention and control of dairy cow mastitis . 20 milk samples from the clinically infected cattle were collected from this cattle farm, and the main pathogens were identified and then used for drug sensitive test. We got 13 from 20 sample,including 6 isolates of Staphylococcus aureus,2 of Staphylococcus epidermidis,1 of E.coli., 3 of Streptococcus agalactiae,1 of Pseudomonas pyocyaneas.The result of sensitivity against 11 kind of common antibiotics shows that all the strains are sensitive to Neomycin Sulfate,Acetylspiramycin,Spectinomycin Doxycycline,and all gram-positive strains are sensitive to Gentamicin Sulfate ,Erythromycin,Kanamycin Sulfate,Chloramphenicol,while the opposite to gram-negative strains. The most popular antibiotics such as Pennicillin,Streptomycin Sulfate,sulfonamide,are not so effective because resistant against antibiotics above produced in majority of them. Key words: dairy cattle mastitis; pathogens; isolation and identification; drug sensitive test(DST) 引 言 奶牛乳房炎是奶牛乳腺组织受到物理，化学，微生物等因素的不良刺激而引起的炎症反应，是奶牛最常见的一种疾病，也是奶牛生产危害性最大的一种疾病。美国乳房炎委员会（NMC）在1978年根据乳房和乳汁有无肉眼可见变化，将奶牛乳房炎分为临床型和隐性型两种。临床型乳房炎主要表现为乳腺组织不同程度的红肿热痛和乳汁变性。隐性乳房炎又称亚临床型乳房炎，无临床症状表现，乳房和乳汁无肉眼可见的异常变化，但乳汁在理化性质和细菌学上已发生变化，实际生产中常被忽视，如不及时治疗，极易转化为临床型乳房