奶牛乳房炎影響奶牛的奶產(chǎn)量和品質(zhì),能引起巨大的經(jīng)濟損失,并嚴重威脅人類的健康�？股厥侵委熌膛Ｈ榉垦椎某Ｓ盟幬�,而細菌具有耐藥的發(fā)展?jié)摿?比如細菌代謝產(chǎn)物超廣譜β-內(nèi)酰胺酶（ESBL）可以使β內(nèi)酰胺酶類藥物失活。ESBL多重耐藥的大腸桿菌日益流行,已受到廣泛的關(guān)注。在獸醫(yī)領(lǐng)域內(nèi),ESBL大腸桿菌的報道多來自于禽、豬,在奶牛方面的報道并不多見。因此,本研究旨在:1)調(diào)查患有臨床型乳房炎的奶牛中產(chǎn)ESBL大腸桿菌的流行情況,并確定編碼ESBL基因的亞型;2)確定ESBL大腸桿菌MCR-1基因的檢出率3)使用紙片法和肉湯稀釋法進行藥敏試驗,確定ESBL和MCR-1陽性大腸桿菌的耐藥性;4)使用限制性片段長度多態(tài)性RFLP、構(gòu)建系統(tǒng)發(fā)育樹等方法對基因盒和插入序列IS進行序列分析;5)對ESBL和mcr-1陽性菌株進行PCR檢測,如質(zhì)粒復制子（PBRT）、多位點序列分型（MLST）,eBURST和geoBURST分析。本研究于2015-2017年從16個省2038份奶牛乳房炎的乳樣中,檢出249株（12%）大腸桿菌,其中產(chǎn)ESBL大腸桿菌49株,高達20%。對這些大腸桿菌進行雙紙片協(xié)同試驗和PC... 

【文章來源】：中國農(nóng)業(yè)大學北京市 211工程院校 985工程院校 教育部直屬院校

【文章頁數(shù)】：135 頁

【學位級別】：博士

【文章目錄】：
摘要
ABSTRACT
LIST OF ABBREVIATIONS
CHAPTER-Ⅰ: GENERAL INTRODUCTION AND REVIEW OF LITERATURE
    1. INTRODUCTION
    2. BOVINE MASTITIS
        2.1. CLASSIFICATION OF BOVINE MASTITIS
        2.2 ETIOLOGY OF BOVINE MASTITIS
        2.3 ESCHERICHIA COLT AS A MASTITIS CAUSING PATHOGEN
        2.4 EPIDEMIOLOGY OF ESCHERICHIA COLI MASTITIS
        2.6 PATHOGENICITY AND PATHOGENESIS OF MASTITIS-ASSOCIATED ESCHERICHIA COLT
        2.7 EFFECT OF ESCHERICHIA COLI INFECTION ON THE MAMMARY GLAND
        2.8. TREATMENT OF ESCHERICHIA COLI MASTITIS
        2.9. ECONOMIC LOSSES OF BOVINE MASTITIS
    3. ANTIMICROBIALS
        3.1 MECHANISMS OF ACTION OF ANTIMICROBIALS
        3.2 USES OF ANTIMICROBIALS IN FOOD-PRODUCING ANIMALS
        3.3 BETA-LACTAM ANTIMICROBIALS
        3.4 ANTIMICROBIAL RESISTANCE
        3.5 MECHANISMS OF ANTIMICROBIAL RESISTANCE
        3.6 THE BETA-LACTAMASES
        3.7 EXTENDED-SPECTRUM BETA-LACTAMASES(ESBLS)AND ESBL ENCODING GENES
        3.8 EPIDEMIOLOGY OF ESBL-PRODUCING ESCHERICHIA COLT IN FOOD ANIMALS
        3.9 COLISTIN RESISTANCE,MCR-1 GENE IN ESCHERICHIA COLT AND THE EPIDEMIOLOGY
    4. PURPOSE AND SIGNIFICANCE OF THE STUDY
    5. KEY QUESTIONS
    6. AIMS OF THE STUDY
CHAPTER-Ⅱ: PREVALENCE AND CHARACTERISTICS OF ESBL-PRODUCINGESCHERICHIA COLI
    1.INTRODUCTION
        1.1 AIMS OF THE STUDY
    2. MATERIALS AND METHODS
        2.1 SAMPLE COLLECTION AND LOCATION
        2.2 ISOLATION AND IDENTIFICATION OF ESCHERICHIA COLT
        2.3 PHENOTYPIC SCREENING OF ESBL-PRODUCERS
        2.4 GENOTYPIC SCREENING OF ESBL-PRODUCING ESCHERICHIA COLT ISOLATES
        2.5 THE POLYMERASE CHAIN REACTION
        2.6 ANTIBIOTIC SUSCEPTIBILITY TESTING
        2.7 PHYLOGENETIC GROUPING
        2.8 DETECTION OF INTEGRONS, GENE CASSETTES AND IS CRI
        2.9 PCR-RFLP ASSAY FOR DETECTION OF GENE CASSETTES
        2.10 NUCLEOTIDE SEQUENCING AND DATA ANALYSIS
    3. RESULTS
        3.1 PREVALENCE AND CHARACTERIZATION OF ESBL-PRODUCING ESCHERICHIA COLT
        3.2 ANTIBIOTIC SUSCEPTIBILITY PROFILES
        3.3 DETECTION OF INTEGRONS,GENE CASSETTES AND IS CRI
        3.4 NUCLEOTIDE SEQUENCES ACCESSION NUMBER
    4. DISCUSSION
    5. CONCLUSION
CHAPTER-Ⅲ: MOLECULAR EPIDEMIOLOGY AND GENETIC DIVERSITY OFESBL-PRODUCING ESCHERICHIA COLL
    1. INTRODUCTION
        1.1 AIMS OF THE STUDY
    2. MATERIALS AND METHOD
        2.1 MILK SAMPLE COLLECTION
        2.2 ISOLATION AND IDENTIFICATION OF ISOLATES AND ESBL PHENOTYPES
        2.3 ANTIBIOTIC SUSCEPTIBILITY TESTING
        2.4 MOLECULAR CHARACTERIZATION OF ESBL-PRODUCING ISOLATES
        2.5 PLASMID REPLICON TYPING
        2.6 RESISTANCE TRANSFER EXPERIMENT
        2.7 MULTILOCUS SEQUENCE TYPING (MLST)OF ES BL-PRODUCING ESCHERICHIA COLI
        2.8 POPULATION STRUCTURE ANALYSIS
        2.9 SEQUENCE COMPOSITIONAL ANALYSIS
        2.10 SPLIT NETWORK AND RECOMBINATION ANALYSIS
    3. RESULTS
        3.1 PREVALENCE AND GENOTYPES OF ESBL-PRODUCING ESCHERICHIA COLI
        3.2 PHYLOGENETIC GROUPING
        3.3 ANTIMICROBIAL RESISTANCE IN ESBL-PRODUCERS
        3.4 PBRT OF ESBL-PRODUCING ESCHERICHIA COLT
        3.5 RESISTANCE TRANSFER EXPERIMENT
        3.6 MLST AND POPULATION STRUCTURE
        3.7 SEQUENCE COMPOSITIONAL ANALYSIS
        3.8 MULTI-LOCUS SEQUENCE ANALYSIS (MLSA)
        3.9 RECOMBINATION ANALYSIS
    4. DISCUSSION
    5. CONCLUSION
CHAPTER-Ⅳ: CO-OCCURRENCE OF MCR-1 AND ESBL GENES INESCHERICHIA COLI
    1. INTRODUCTION
        1.1 AIMS OF THE STUDY
    2. MATERIALS AND METHODS
        2.1 THE STUDY AND ISOLATION OF ESCNERICHIA COLI
        2.2 ANTIMICROBIAL RESISTANT PHENOTYPES
        2.3 DETECTION OF MCR-1 GENE AND OTHER RESISTANCE GENES
        2.4 INTEGRON AND PLASMID TYPING OF MCR-1 POSITIVE ISOLATES
        2.5 CONJUGATION EXPERIMENT
        2.6 MULTILOCUS SEQUENCE TYPING AND ANALYSIS
    3. RESULTS
        3.1 CO-OCCURRENCE OF MCR-1 AND ESBL ENCODING GENES
        3.2 ANTIMICROBIAL SENSITIVITY PROFILE
        3.3 CHARACTERIZATION OF INTEGRONS AND VARIABLE REGIONS
        3.4 PLASMID REPLICON TYPING AND RESISTANCE TRANSFER EXPERIMENTS
        3.5 MULTILOCUS SEQUENCE TYPING AND ANALYSIS
    4. DISCUSSION
CHAPTER-Ⅴ: CONCLUSIONS AND RECOMMENDATIONS
NOVELTY OF THE STUDY
REFERENCES
ACKNOWLEDGEMENT
AUTHOR'S SHORT CV
Annexures



本文編號：3297041