論文宣讀

稻稈是水稻收穫後殘餘的農副產物，可應用為反芻動物的替代芻料。本研究比較脆性水稻突變品種稻稈(PB3)、野生型水稻品種稻稈(IR64)與百慕達乾草 (BH)在體外發酵之下瘤胃微生物的變化，並在不同的培養時間點（0、4、8、12 和 24 小時）測量乾物質 (DM) 降解程度和 pH 值。從體外培養的瘤胃液中分離出總基因體DNA，用以驗證總細菌、擬桿菌屬、普雷沃氏菌屬和瘤胃球菌屬之菌相，並使用即時定量聚合酶連鎖反應 (qPCR) 技術量化相對豐富度。結果顯示，所有處理組的乾物質降解率均隨培養時間增加而提升，而瘤胃液pH值隨培養時間增加顯著降低（P < 0.05）。BH組培養24小時顯示最高的乾物質降解率（28.68 %）和最低的pH值（6.61）。BH和PB3組培養0和4小時之優勢細菌為擬桿菌屬，然而在培養24小時後被普雷沃氏菌屬取代。瘤胃球菌屬之豐富度在IR64處理組中隨著培養時間增加略有提升，於 PB3 處理組中則穩定存在。在正常瘤胃發酵情形之下，脆性稻稈對於瘤胃微生物菌相呈現不同的動態變化，為了進一步了解，需測試特定微生物及其相對應的營養成分。
關鍵詞：瘤胃微生物、稻稈、即時定量聚合酶連鎖反應 (qPCR)

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