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红霉素与四环素耐药基因在猪链球菌临床分离株中的检测 总被引：1，自引：1，他引：0
为了解临床分离的48株猪链球菌对大环内酯类药物及四环素耐药基因的分布,用微量稀释法测定48株临床分离的猪链球菌对大环内酯类、四环素、β-内酰胺类及头孢类9种抗生素的药物敏感性,建立PCR方法对耐药菌株大环内酯类耐药基因ermA/B/C、mefA/E、msrD、mphB、23S rRNA,L4,L22和四环素耐药基因tetM、tetO、tetL、tetK及与Tn916转座子相关的int和xis基因进行检测。结果表明,31株2型猪链球菌中大环内酯类药物耐药率为3.23%,17株9型猪链球菌红霉素耐药率为88.24%,泰乐菌素、磷酸替米考星、阿奇霉素的耐药率均为70.59%。48株猪链球菌对四环素均耐药,但对青霉素、阿莫西林、头孢曲松钠、氨苄西林均敏感。大环内酯类耐药基因主要以ermB为主,占75%(12/16),mefA/E、msrD占25%(4/16),16株红霉素耐药菌株中,tetM、tetO、int、xis的检出率分别为25%(4/16)、62.5%(10/16)、31.25%(5/16)和31.25%(5/16),没有检测到ermA、ermC、mphB、tetL、tetK。所有红霉素耐药菌株均未检测到23S rRNA、L4和L22突变。 相似文献
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为了解内蒙古地区奶牛乳房炎链球菌毒力基因的分布情况及其耐药现状,通过该地区360份乳房炎奶样链球菌的分离鉴定,利用微量肉汤稀释法测定了81株链球菌对15种药物的MIC,采用PCR法检测耐药基因及毒力基因的携带情况。结果显示,分离到的81株链球菌对β-内酰胺类的耐药率最高;对红霉素和四环素的耐药率在40%~85%;对氟喹诺酮类的耐药率相对较低。多重耐药菌株达88.9%(n=72)。耐药基因pbp2b的检出率为86.4%,tetL和tetM的检出率在75%以上,红霉素耐药表型主要由ermB介导。分离菌株毒力基因中cfb的检出率最高(50.6%),其次为cyl和hylB。内蒙古地区奶牛乳房炎链球菌对β-内酰胺类、大环内酯类和四环素耐药情况严重,且发现多重耐药菌株的流行;链球菌中尤以无乳链球菌的毒力基因携带率较高。 相似文献
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《中国兽医学报》2015,(7):1130-1135
对江苏地区多个奶牛场采样,并对奶牛乳房炎(Bovine mastitis,BMT)检测阳性奶样进行病原菌分离、鉴定。对分离出的凝固酶阴性葡萄球菌(Coagulase-negative Staphylococci,CNS)分别进行20种药物的敏感性试验和相关耐药基因检测。结果显示,BMT检测阳性的奶样有610份,528份检出细菌,共检出细菌802株,鉴定为CNS的217株;大部分CNS对万古霉素、左氟沙星、氯霉素、磷霉素、呋喃妥因敏感,对青霉素、大观霉素具有较强耐药性;CNS对β-内酰胺类(blaZ)、大环内酯类(ermC)和四环素类(tetK、tetM、tetL、tetO)耐药基因的检出率分别为29.95%、2.30%、24.88%、1.84%、1.84%和0.00%。 相似文献
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东北部分地区猪链球菌对四环素类药物耐药机制的研究 总被引：5，自引：0，他引：5
为了研究东北部分地区猪链球菌对四环素类药物的耐药机制,在兰氏分群的基础上,对东北部分地区分离的12株猪链球菌进行四环素类药物的耐药性测定和相关基因的扩增。结果表明:12株猪链球菌均属于D群,其中91.7%对多西环素耐药,100%对土霉素耐药,83.3%对盐酸金霉素耐药;12株菌均扩增出tetM基因,但未扩增出tetO基因。同源性分析结果显示扩增的tetM基因与GenBank中的肺炎链球菌、粪肠球菌等的tetM基因的同源性为94%~100%。 相似文献
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《黑龙江畜牧兽医》2017,(10)
为了解新疆阿克苏地区致奶牛乳房炎性大肠杆菌的耐药性及其耐药基因的流行状况,从患有乳房炎的奶牛病例中分离出20株大肠杆菌,采用K-B(Kirby-Bauer)法对其耐药性进行了检测,对其耐药基因进行了分子生物学检测。结果表明:分离菌株对氨苄西林的耐药性最高,耐药率达到了50%,对多西环素、四环素和链霉素的耐药性次之,耐药率为40%,而对环丙沙星、阿米卡星、诺氟沙星则比较敏感;能够检出的毒力基因为astA、escV、eaeA、sepA和hlyA,能够扩增出的耐药基因为tetB、tetC、GyrA、GyrB和ParC。说明新疆阿克苏地区奶牛乳房炎源大肠杆菌主要携带四环素和氟喹诺酮类耐药基因,耐药菌株的耐药基因型与耐药表型呈现正相关。 相似文献
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奶牛乳房炎致病型耐甲氧西林金黄色葡萄球菌的分离鉴定 总被引：1，自引：0，他引：1
为探究引起奶牛乳房炎的耐药性致病菌,本研究针对西安地区显性乳房炎奶样中的耐甲氧西林金黄色葡萄球菌（MRSA）进行系统研究。采用常规细菌学鉴定法对34头（次）荷斯坦牛76个乳区152份奶样的金黄色葡萄球菌（Staphylococcus aureus,S.aureus）进行了分离培养,共检出92株阳性菌株,检出率为60.5%;对其进行S.aureus致病基因nuc的特异性PCR检测,共检出28株含nuc基因的阳性菌株,检出率为30.4%;进一步针对MRSA耐药基因mecA进行特异性PCR扩增,共检出5株MRSA,检出率为17.9%。研究结果为MRSA耐药菌的有效检测及奶牛乳房炎的治疗提供了指导。 相似文献
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奶牛乳房炎分离大肠杆菌的耐药性及脉冲场凝胶电泳分型研究 总被引：1，自引：0，他引：1
为了解宁夏地区奶牛乳房炎分离大肠杆菌的耐药表型及同源性特征,本试验采用肉汤微量稀释法测定了16种抗菌药物对66株奶牛乳房炎分离大肠杆菌的最低抑菌浓度(MIC),同时进行了脉冲场凝胶电泳(PFGE)分子分型研究.结果显示,66株大肠杆菌对氨苄西林、链霉素、四环素、多西环素、头孢菌素类抗生素和磺胺甲氧嘧啶的耐药率都比较高,而对阿米卡星、卡那霉素、多粘菌素、氟苯尼考及喹诺酮类药物则比较敏感.分离菌株最多耐受15种药,且主要以8耐、5耐和7耐为主.66株大肠杆菌中有54株能被PFGE分型,可分为A-a 27个型.分型结果显示,宁夏地区的奶牛场分离的菌株之间既存在垂直传播也存在水平传播,同一养殖场不同奶牛之间和不同养殖场的奶牛之间存在多重耐药大肠杆菌的克隆传播. 相似文献
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《中国奶牛》2017,(8)
为了解奶牛场乳房炎金黄色葡萄球菌(Staphylococcus aureus,S.aureus)的耐药性,并对耐甲氧西林金黄色葡萄球菌(MRSA)的耐药基因进行研究,本研究采集奶牛场临床型乳房炎奶样89份进行金黄色葡萄球菌分离鉴定及药敏试验,采用K-B法检测其对常用13种抗生素的敏感性;利用双重PCR扩增MRSA的nuc基因和mec A耐药基因;应用基因外重复回文序列(repetitive extragenic palindromic elements,REP)PCR对分离菌株进行基因多样性分析。结果显示,共分离到16株MRSA;在监测的13种药物中,耐药率超过50%的达到10种,其中对头孢曲松(CRO)、头孢噻肟(CTX)、环丙沙星(CIP)和亚胺培南(IPM)耐药率高达93.75%(15/16),但未见对头孢呃酮(SCF)耐药的分离菌株;耐药基因检测结果显示,16株菌中都携带有mec A耐药基因,除1株外其他15株分离菌都携带特异致病nuc基因。REP-PCR把分离菌株分为13种基因型(A-M),同源性≥90%的只有6株菌。研究结果表明,奶牛乳房炎金黄葡萄球菌的多重耐药比较严重,分子多样性复杂,mec A是其耐甲氧西林类药物的重要机制,本研究为MRSA耐药菌的有效检测及奶牛乳房炎的治疗提供了科学依据。 相似文献
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[目的]通过系统进化群和耐药性分析,了解鸡源大肠杆菌致病菌株的分布情况及耐药特征,为有效控制鸡大肠杆菌病提供依据。[方法]采用微量肉汤稀释法测定菌株耐药表型（MIC）,采用PCR法检测耐药基因和系统进化群分群试验,采用SPSS17.0软件进行差异显著性分析。[结果]低致病群B1（38.1%）和非致病群A（34.0%）菌株分布相对较多,其次是高致病群D（21.2%）和B2（6.2%）;分离菌株对氨苄西林（87.2%）、四环素（87.0%）、复方新诺明（87.0%）和磺胺异噁唑（80.0%）耐药严重,多重耐药率高达98.86%,但对多粘菌素E敏感;耐药基因sul1（71.0%）、sul2（44.8%）、sul3（18.7%）、tetA（42.2%）、tetB（15.8%）、tetM（7.3%）均有检出,tetC、tetO、tetK、tetL、tetW均未检出,9.13%菌株同时携带3种sul基因,仅有一株菌同时携带3种tet基因。表型耐药菌株携带耐药基因的能力明显高于非耐药菌株（P<0.05）。高致病群B2、D群耐药程度较B1和A群严重,对氧氟沙星、庆大霉素、大观霉素、头孢噻呋、磺胺异噁唑、复方新诺明、奥格门丁等7种药物差异显著（P<0.05）。[结论]我国鸡源大肠杆菌高致病菌株检出率高,且耐药程度相对严重,在适宜条件下更易导致鸡群发病且难以控制。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献