[目的]探究生牛乳受芽孢杆菌属污染的影响因素,分析芽孢杆菌存在不同形态的原因。[方法]采用基质辅助激光解吸电离飞行时间质谱仪（MALDI-TOF-MS）测定生牛乳中芽孢杆菌的种类。[结果]本研究共分离出8 株短芽孢杆菌属、2 株类芽孢杆菌属,其中未邀短芽孢杆菌存在2 种菌落与菌体形态,长杆或细丝形态属于未邀短芽孢杆菌的特殊形态。[结论]菌落形态随传代次数与培养时间延长呈规律性变化,菌体形态无明显规律。芽孢杆菌污染的主要因素与奶牛卧床、挤奶人员手部、擦拭乳区毛巾及设备等消杀有关。本研究为芽孢杆菌防控提供新的形态学见解,为相关防控提供理论依据。
[Objective] To investigate the influencing factors of Bacillus contamination in raw milk and analyze the reasons for the different forms of Bacillus.[Method] The species of Bacillus in raw milk were determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry（MALDI-TOF-MS）.[Result] In this study, 8 strains of Brevibacillus and 2 strains of Paenibacillus were isolated,among which there were 2 types of colony and morphology of Brevibacillus invocatus,and the long rod or filamentous form belonged to the special morphology of Brevibacillus invocatus.[Conclusion] The morphology of colonies changed regularly with the passage times and culture time,but there was no obvious pattern. The main factors of Bacillus contamination were related to the disinfection of cow bed,milkers’hands,wiping towels and equipments in the milk area. This study provided new morphological insights for the prevention and control of Bacillus and provided theoretical basis for related prevention and control.
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