臺灣博碩士論文加值系統

副豬嗜血桿菌 (Haemophilus parasuis; HP) 可造成豬隻的格拉氏病 (Glässer’s disease)，常引起4至8週齡保育豬的纖維素性多發性漿膜炎、關節炎與腦膜炎。根據傳統血清學方法，HP雖已可被劃分成15種血清型，卻並不是所有菌株均能依此方法被分型；若能以分子生物學方法進行血清分型，則可以改善此缺失。基因分型方法之多重基因座序列分型 (multilocus sequence typing; MLST)，因是分析管家基因 (housekeeping gene) 的序列，故常被用於流行病學的調查。另由於抗藥性菌株在許多國家陸續被發現，故藥物敏感性現況亦成為關注的重點。本研究菌株來自於2012 ~ 2017年間送檢至國立嘉義大學獸醫學院附設雲嘉南動物疾病診斷中心之109個病例，共分離得117株HP，送檢病例除多集中於日夜溫差變化較大的月份與4 ~ 10週齡保育豬之好發族群外，亦和豬生殖與呼吸綜合症病毒、豬鼻炎黴漿菌、豬巨大細胞病毒與豬鏈球菌的混合感染具有顯著的相關性。前述菌株所盛行的血清型以第4 (28.1%)、5 (25.0%) 與12 (20.8%) 血清型為主，再依序為第13 (8.3%)、無法分型 (8.3%)、9 (3.1%)、14 (3.1%)、1 (2.1%) 與7血清型 (1.0%)。若以MLST分型，則發現71個新的對偶基因與72個新的基因型，前述新的基因型經Based Upon Related Sequence Types (BURST) 演算後，又可再分成8個群聚與37個獨體，於以Unweighted Pair Group Method with Arithmetic mean (UPGMA) 繪製之樹狀圖中，本研究所有的菌株除與大部分MLST資料庫中致病性菌株皆位於同一群 (cluster) 外，且幾乎所有較具致病性的第4、5、12、13與14血清型菌株也位在相同群別。此外，其中109株HP於藥物感受性試驗結果中，對於ceftiofur的感受性最高 (98.2%)，其次為florfenicol (90.6%)，tiamulin亦見高度的感受性，penicillin、tilmicosin與enrofloxacin呈現中等程度感受性，amoxicillin、tetracycline與trimethoprim-sulfamethoxazole之敏感性比例皆差；另值得關注的是：85.9%的菌株對3種以上的抗菌劑具有抗藥性。

Haemophilus parasuis (HP) causes Glasser’s disease and pneumonia in pigs. The characteristic lesions include fibrinous polyserositis, polyarthritis and meningitis. 15 serotypes have been identified in serolgical methods, but the high percentage of assigned to nontypable isolates led to the development of molecular serotyping method. Besides, MLST has been developed to investigate the epidemiology of HP population. Antimicrobial treatment is effective against HPS infection. However, the resistance against many kinds of antimicrobial agents has been discovered in recent years. A total of 117 HP were isolated from diseased pigs at Animal Disease Diagnostic Center of National Chiayi University in Taiwan from 2012 to 2017. Glasser’s disease outbreaks usually occured with temperature changed dramatically, and 4 to 10 week-old weaned pigs were more susceptible. Significant associations between HP and porcine reproductive and respiratoey virus, Mycoplama hyorhinis, porcine cytomegalovirus, Streptococcus suis were identified. Serotype 4 (28.1%), 5 (25%) and 12 (20.8%) strains were most prevalent, followed by serotype 13 (8.3%), non-typable (8.3%), 9 (3.1%), 14 (3.1%), 1 (2.1%) and 7 (1.0%). 71 new alleles and 72 new sequence types (STs) were detected, and 72 STs were grouped into 8 clonal complexes and 37 singletons. In Unweighted Pair Group Method with Arithmetic mean dendrogram, one cluster included all 117 isolates with most virulent isolates in MLST database, so did serotyping serotype 4, 5, 12, 13 and 14 isolates. The percentages of antimicrobial resistance against penicillin, amoxicillin, ceftiofur, tetracycline, enrofloxacin, florfenciol, tilmicosin and tiamulin were 46.8%, 71.7%, 1.8%, 96.3%, 62.3%, 9.4%, 67.9% and 24.5%, respectively. Besides, 85.9% isolates showed multi-antimicrobial resistance.

中文摘要 I
Abstract II
目錄 III
表圖次 V
第一章 前言 1
第二章 文獻探討 2
第一節 副豬嗜血桿菌介紹 2
2.1.1 細菌特性與培養條件 2
2.1.2 臨床表現及病理變化 2
2.1.3 致病機制 3
第二節 血清型別分類 3
2.2.1 血清型別分類方法 3
2.2.2 血清型及發病型態相關性 5
2.2.3 血清型及疫苗效力相關性 5
2.2.4 各國HP血清型分布概況 6
第三節 多重基因座序列分型 7
第四節 各國抗藥性概況 8
2.4.1 丹麥 8
2.4.2 西班牙與英國 9
2.4.3 捷克 10
2.4.4 澳洲 10
2.4.5 中國 10
2.4.6 臺灣 12
第三章 材料與方法 13
第一節 研究目的與動機 13
第二節 菌株收集、分離、培養及保存 13
第三節 副豬嗜血桿菌血清型鑑定 14
第四節 副豬嗜血桿菌之多重基因座序列分型 14
第五節 藥物感受性試驗 15
第六節 統計分析 15
第四章 結果 17
第一節 病例資料分析 17
第二節 格拉氏病混合感染之病原 17
第三節 副豬嗜血桿菌之菌株資料與血清分型 18
第四節 多重基因座序列分型 19
第五節 UPGMA樹狀圖分析 20
第六節 藥物感受性試驗結果 21
第五章 討論 22
第六章 結論 32
第七章 參考文獻 33

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