奶牛乳房炎重要致病菌和常用抗菌药物体外在牛奶中的分布  

Distribution of major mastitis-causing bacteria and common antimicrobial drugs in milk

作　　者：曹立亭[1] 胡松华[1] 

机构地区：[1]浙江大学奶业科学研究所,浙江杭州310029

出　　处：《中国兽医学报》2010年第10期1381-1384,共4页Chinese Journal of Veterinary Science

基　　金：浙江省支疆项目;浙江省"三农五方"项目(2005C1-2015);杭州市重大科技攻关项目(2005211A06)

摘　　要：为了解奶牛乳房炎重要致病菌和常用抗菌药物在乳房内的分布情况,本试验分析了一次挤奶过程中不同时间段牛奶的主要乳成分变化,并研究了金黄色葡萄球菌和大肠杆菌以及常用抗菌药物体外在牛奶中的分布。结果表明,随着挤奶过程的进行,牛奶中的脂肪含量逐渐升高,挤奶后期显著高于挤奶前期和中期(P<0.05),而乳蛋白和乳糖含量变化不大;金黄色葡萄球菌和大肠杆菌主要富集在牛奶的上部,细菌计数上部显著高于中部和下部(P<0.01);常用抗菌药物盐酸林可霉素、青霉素钠、硫酸庆大霉素、盐酸四环素、氨苄西林钠、乳糖酸红霉素、乳酸环丙沙星、头孢噻呋钠在牛奶中下部显著高于上部和中部,乳酸链球菌素Nisin Z在牛奶中分布比较均匀,并在上部略高。本研究结果提示,经奶牛乳头管进入的细菌可以随牛奶中的脂肪滴上浮,侵入乳腺的深层组织;乳房炎致病菌和常用治疗药物在乳房中分别向上下两极移动,这种分布上的分离现象可导致抗菌药物和致病菌不能充分接触,可能是临床上乳房炎治疗失败的一个原因。This study was designed to investigate variations in major constituents of milk during milking in dairy cows,and in vitro distribution of major mastitis-causing bacteria and common antimicrobial drugs in milk.Results indicated that the concentration of fat gradually increased with the progress of milking,and was significantly higher in the milk collected during the last period than those collected during other period of milking;the concentration of milk protein and lactose changed little.Staphylococcus aureus and Escherichia coli were found largely in upper portion of the milk,and the colony forming units（CFU）/mL of both S.aureus and E.coli were significantly higher than those in middle and lower portions（P0.01）.Antibacterial drug benzylpenicillin sodium,gentamycin sulfate,ciprofloxacin lactate,ceftiofur sodium,lincomycin hydrochloride,erythromycin lactobionate,tetracycline hydrochloride,ampicillin sodium were found to have significantly higher concentration in lower portion of milk than in middle and upper portions.Nisin Z was distributed more evenly but a little higher concentration in the upper portion.It is suggested that bacteria getting entrance into teat canal may float up through attaching to fat globes and invade the deep tissues.Bacteria and antibacterial drugs may not contact each other sufficiently due to their contra-direct movements,resulting in poor response of mastitic cases to antibacterial therapy.

关 键 词：乳房炎 金黄色葡萄球菌 大肠杆菌 抗菌药物 

分 类 号：S857.26[农业科学—临床兽医学]