中国畜牧兽医

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奶牛乳房炎无乳链球菌活菌数与吸光度之间相关性研究

肖敏1,杨峰2,王旭荣2,罗金印2,李新圃2,贾宁1,李宏胜2   

  1. 1.甘肃农业大学动物医学院,甘肃兰州  7300702.中国农业科学院兰州畜牧与兽药研究所,甘肃兰州  730050

  • 收稿日期:2013-12-03 出版日期:2014-05-20 发布日期:2014-06-25

Relations Between Bacterial Count and Absorbance of Streptococcus agalactiae in Bovine Mastitis

XIAO Min1,YANG Feng2,WANG Xu-rong2,LUO Jin-yin2,LI Xin-pu2,JIA Ning1,LI Hong-sheng2   

  1.  (1.College of Veterinary MedicineGansu Agricultural UniversityLanzhou 730070China2.Lanzhou Institute of Husbandry and Pharmaceutical Science of CAASLanzhou 730050China)

  • Received:2013-12-03 Online:2014-05-20 Published:2014-06-25

摘要: 为了建立一种通过吸光度测定能够快速准确检测奶牛乳房炎疫苗中无乳链球菌抗原浓度的方法,本试验将血平板培养的无乳链球菌用生理盐水将菌苔洗下,稀释成不同浓度的细菌悬浮液,然后用平板计数法测定不同浓度菌液的活菌数,同时测定其相应的吸光度,进而研究二者之间的相关性,建立标准曲线。结果表明,无乳链球菌的活菌数与其吸光度呈直线线性相关,无乳链球菌菌液浓度与吸光度之间的回归方程为y=7.5861x-0.0805,R2=0.9735,通过测定细菌悬浮液的吸光度,可以快速计算出该菌的菌液浓度。笔者对发酵罐培养的5批无乳链球菌菌液进行了吸光度测定和传统平板计数方法的比较及验证,证明了吸光度测定法优于平板计数法,具有简单、快速、准确的特点。

关键词: 奶牛乳房炎; 无乳链球菌; 活菌数; 吸光度; 相关性

Abstract: The present study was aimed to establish a method for quickly and accurately calculating the concentration of Streptococcus agalactiae antigen in dairy cow mastitis vaccine. Streptococcus agalactiae were washed from blood plate using physiological saline and diluted into different concentrations of bacteria suspension,which were used to calculate the number of viable bacteria suspension by plate count method.Meanwhile the corresponding absorbance (A450 nm) were determined. Then established the standard curve through the correlation between concentrations and absorbance.The result showed that the viable bacteria counts had a significant linear correlation with the absorbance of Streptococcus agalactiae.Thus,we build a regression equation between Streptococcus agalactiae bacteria suspension concentration and absorbance was y=7.5861x-0.0805,R2=0.9735,through which we could quickly calculate Streptococcus agalactiae concentration by measure the absorbance of its suspension.Compared to traditional plate count method,the absorbance measurement accuracy of the method was verified better by 5 batches of Streptococcus agalactiae bacteria suspension fostered by fermentor,and proved the new method has characteristics of simple,fast and accurate.

Key words:

bovine mastitis; Streptococcus agalactiae; bacterial count; absorbance; relations