本文選題：大腸桿菌　切入點：耐藥性　出處：《寧夏大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：大腸桿菌(Escherichia coli, E. coli),獸醫(yī)臨床上最常見的病原菌之一,可引起人和家畜禽的多種疾病,如引起幼畜嚴(yán)重腹瀉和敗血癥、豬水腫病、人的出血性結(jié)腸炎-溶血性尿毒綜合征、新生兒腦膜炎及腎炎等多種疾病。隨著養(yǎng)殖業(yè)的逐漸規(guī)模化,抗菌藥物的過度使用,導(dǎo)致大腸桿菌的耐藥性及其多重耐藥性已嚴(yán)重影響了獸醫(yī)臨床疾病的治療,因此對本地區(qū)奶牛乳房炎大腸桿菌進行毒力基因檢測和耐藥性分析及耐藥性分子流行病學(xué)的調(diào)查,不但對大腸桿菌引起的疾病防治具有指導(dǎo)意義,而且有利于控制耐藥菌株的產(chǎn)生和傳播。本研究采用微生物學(xué)和分子生物學(xué)方法對寧夏地區(qū)部分奶牛場臨床型及隱性乳房炎奶樣,進行大腸桿菌分離鑒定,應(yīng)用CLSI(2012)推薦的紙片擴散法(K-B)對其進行抗菌藥物敏感性試驗,采用O抗原平板凝集試驗鑒定大腸桿菌優(yōu)勢血清型,運用PCR擴增方法對大腸桿菌毒力基因及耐藥基因進行檢測。1.2011-2013年采集寧夏地區(qū)部分奶牛場臨床型及隱性乳房炎奶樣,進行大腸桿菌的分離鑒定。通過觀察大腸桿菌顯色培養(yǎng)基上細(xì)菌菌落形態(tài)、革蘭氏染色鏡檢和PCR擴增16S rDNA等方法進行大腸桿菌的鑒定,最終分離鑒定出197株大腸桿菌。2.根據(jù)有關(guān)文獻,選取38種大腸桿菌O抗原血清,對197株奶牛乳房炎大腸桿菌進行O抗原血清鑒定。鑒定結(jié)果顯示,共有138株大腸桿菌被鑒定出血清型,優(yōu)勢血清型有0127(35/138)0158(16/138)和044(12/138),有6株為自凝,53株未定型。3.對197株奶牛乳房炎大腸桿菌進行16種常用抗菌藥物的敏感性試驗,結(jié)果顯示,所分離的大腸桿菌對氨芐西林耐藥率最高,達到了54.69%,其次對多西環(huán)素(39.59%)、四環(huán)素(39.09%)和鏈霉素(38.58%)的耐藥率也較高。而對頭孢類、多粘菌素、氟苯尼考和喹諾酮類藥物則比較敏感,敏感率都在60%以上。分離株最多耐受15種抗菌藥物。4.采用PCR方法對197株奶牛乳房炎大腸桿菌進行了毒力基因和耐藥基因的檢測,結(jié)果顯示,毒力基因astA、eaeA、hlyA、escV和sepA以及耐藥基因tetB、tetC、GyrA、GyrB和ParC都被檢出。其中astA檢出率是21.13%,hlyA檢出率最低,只有1.02%。四環(huán)素類的2種耐藥基因tetC的陽性率為14.72%,tetB的陽性率是7.61%；氟喹諾酮類的GyrA、GyrB和ParC三種耐藥基因檢出率非常高,分別為97.46%、98.98%和98.48%。綜上所述,本研究通過對寧夏地區(qū)奶牛乳房炎大腸桿菌血清型、毒力基因和耐藥基因的檢測及耐藥性分析,初步揭示了本地區(qū)牛源大腸桿菌的耐藥情況及毒力基因的流行情況,為指導(dǎo)抗菌藥物在臨床上的合理應(yīng)用以及預(yù)防和控制耐藥菌傳播提供了科學(xué)依據(jù)。
[Abstract]:E. coli Escherichia coli, E. coli, one of the most common pathogens in veterinary practice, can cause many diseases in humans and domestic animals, such as severe diarrhea and septicemia in young animals, edema in pigs, hemorrhagic colitis and hemolytic uremic syndrome in human beings. Neonatal meningitis and nephritis and other diseases. With the gradual scale of aquaculture, the excessive use of antimicrobial agents, leading to the drug resistance of Escherichia coli and multidrug resistance has seriously affected the treatment of veterinary clinical diseases. Therefore, the detection of virulence gene, the analysis of drug resistance and the investigation of molecular epidemiology of drug resistance in dairy cow mastitis Escherichia coli in this area are not only of guiding significance for the prevention and treatment of diseases caused by E. coli. In this study, microbiological and molecular biological methods were used to isolate and identify clinical and recessive mastitis samples from some dairy farms in Ningxia. The antimicrobial susceptibility test was carried out by using the disk diffusion method (K-B-) recommended by CLSI (2012), and the predominant serotype of Escherichia coli was identified by O antigen plate agglutination test. The virulence genes and drug resistance genes of Escherichia coli were detected by PCR amplification. 1. Clinical and recessive mastitis samples were collected from dairy farms in Ningxia from 2011 to 2013. The colony morphology of Escherichia coli on color-forming medium was observed, microscopical examination of Gram stain and 16s rDNA amplification by PCR were used to identify Escherichia coli. Finally, 197 strains of Escherichia coli were isolated and identified. According to the related literature, 38 kinds of Escherichia coli O antigen serum were selected and 197 strains of cow mastitis Escherichia coli were identified by O antigen serum. A total of 138 strains of Escherichia coli were identified as serotypes. The predominant serotypes were 01277 / 35 / 138 / 015816 / 138) and 044 / 12 / 138C, and 6 strains were self-coagulant 53 strains of untyped .3.The sensitivity tests of 16 common antimicrobial agents against 197 strains of dairy cow mastitis Escherichia coli were carried out, and the results showed that, The highest resistance rate of Escherichia coli to ampicillin was 54.69, followed by doxycycline 39.59, tetracycline 39.09) and streptomycin 38.58), but sensitive to cephalosporins, polymyxin, florfenicol and quinolone. The sensitivity rate was above 60%. The isolates were resistant to 15 antimicrobial agents. The virulence genes and drug resistance genes were detected by PCR method. The virulence gene, astAeae, hly AescV and sepA, as well as the resistant gene tetBntetCnGyrB and ParC were detected, and the detection rate of astA was the lowest, and the detection rate of astA was the lowest. The positive rate of tetC was 14.72% for tetB and 7.61 for fluoroquinolones GyrAgyrB and ParC, respectively, which were 97.46% and 98.48%, respectively. In this study, the serotypes, virulence genes and drug resistance genes of E. coli from dairy cattle in Ningxia area were detected and drug resistance was analyzed, and the situation of drug resistance and the prevalence of virulence genes were preliminarily revealed. It provides a scientific basis for the rational application of antimicrobial agents in clinic and the prevention and control of the spread of drug resistant bacteria.
【學(xué)位授予單位】：寧夏大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：S852.612

【參考文獻】

相關(guān)期刊論文 前10條

1 焦顯芹;肖方;劉河冰;李新生;杜向黨;;氨基糖苷類藥物高水平耐藥16S rRNA甲基化酶的研究進展[J];中國畜牧獸醫(yī);2009年06期

2 ZHANG Yan-ying;GAO Gui-sheng;GE Mu-xiang;GAO Guang-ping;SHI Qiu-mei;WANG Yan-yan;LIU Li-li;;The Detection of Pathogenic Porcine E.coli Virulence Gene (astA,stb)[J];Animal Husbandry and Feed Science;2012年04期

3 鄧光存;包少文;楊繼輝;曾瑾;李武;劉曉明;;產(chǎn)腸毒素大腸埃希菌STa-K99融合蛋白重組腺病毒載體的構(gòu)建及表達[J];動物醫(yī)學(xué)進展;2013年10期

4 夏利寧;向發(fā);郭慶勇;南海辰;底麗娜;姚剛;;新疆不同地區(qū)牛源大腸桿菌耐藥性分析[J];中國畜牧獸醫(yī);2014年02期

5 史秋梅;張艷英;高桂生;高光平;劉玉芹;房海;陳翠珍;沈慶鵬;;大腸桿菌毒力基因Colv、Stxs和HlyE的PCR檢測(英文)[J];Agricultural Science & Technology;2012年10期

6 王喜鳳;趙志明;;奶牛乳房炎診療體會[J];農(nóng)業(yè)技術(shù)與裝備;2012年15期

7 楊滴;王耀兵;李冬梅;宮強;蘇潔;;糞便中大腸埃希菌的分離鑒定[J];微生物學(xué)雜志;2007年03期

8 薛濤;陳先亮;高崧;劉秀梵;;產(chǎn)志賀毒素大腸桿菌O18 XZ113株主要毒力基因eaeA、stx2、ehxA突變株的構(gòu)建及其對小鼠的致病作用[J];微生物學(xué)報;2011年12期

9 楊漢春,陳聲,吳清明,查振林,郭鑫;雞源大腸桿菌對氟喹諾酮類藥物的多重耐藥性[J];畜牧獸醫(yī)學(xué)報;2003年04期

10 張春榮,蘇亞拉圖;我國流行的雞致病性大腸桿菌血清型[J];中國動物檢疫;1996年01期

相關(guān)博士學(xué)位論文 前1條

1 劉曉強;寵物源大腸桿菌對氟喹諾酮類藥物的多藥耐藥機制研究[D];西北農(nóng)林科技大學(xué);2012年

相關(guān)碩士學(xué)位論文 前4條

1 杜冬冬;一株豬源大腸桿菌的分離鑒定及耐藥性分析[D];山東農(nóng)業(yè)大學(xué);2012年

2 張書蕭;大腸桿菌O157的分子流行病學(xué)調(diào)查和毒力因子研究[D];吉林農(nóng)業(yè)大學(xué);2012年

3 黃佳佳;大腸桿菌不耐熱腸毒素突變蛋白的表達及其對粘膜免疫效果的影響[D];揚州大學(xué);2012年

4 黃名錢;豬源大腸桿菌四環(huán)素耐藥基因檢測及大腸桿菌抑制劑篩選[D];江西農(nóng)業(yè)大學(xué);2013年

，

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