在内蒙古的牛乳腺炎衍生Bacillus cereus:菌株特征,病毒性因子识别和病原性验证
Chen Yu1,2, Kollie Helena Vivian1,2, Shuangyuan Fan1,2
1Joint International Research Laboratory of Agriculture and Agri-Product Safety, Ministry of Education of China, Yangzhou University, Yangzhou 225009, China.
Veterinary sciences
|November 26, 2025
概括
谷菌是内蒙古乳牛群中日益严重的威胁,导致牛乳炎. 这项研究揭示了它对常见抗生素的耐药性,并突出了特定毒性基因与疾病严重程度之间的联系.
科学领域:
- 兽医微生物学 兽医微生物学
- 流行病学 流行病学
- 抗微生物耐药性 抗微生物耐药性
背景情况:
- 牛乳炎在乳制品生产中带来了重大的经济和动物福利挑战.
- 麦芽菌 (B. cereus) 越来越多地被认为是牛乳腺炎的病原体,但其流行病学特征和特定地区的毒性因素需要进一步研究.
研究的目的:
- 调查内蒙古牛乳炎中B. cereus的流行病学特征.
- 确定B. cereus分离物的抗微生物耐药性模式和毒性基因配置文件.
- 评估B. cereus相关性乳腺炎中毒性因素的临床影响.
主要方法:
- 在三家奶牛农场进行了涉及340种细菌分离物的横截面研究,来自108只患有临床乳腺炎的奶牛.
- 细菌学分析,抗菌素敏感性测试 (Kirby-Bauer盘扩散) 和PCR用于病毒性基因分析.
- 鼠标挑战实验以评估基于毒性因子存在的病原性.
主要成果:
- B. cereus 是主要的病原体 (30.58%),其次是 Staphylococcus spp. (21.76%) 的比例.
- 观察到对四环素,科特里莫克萨和西普罗夫洛克萨的高耐药性;对 جنت米辛,阿米卡辛和罗克西菌素完全敏感.
- 所有分离物都携带了nheA,nheB和entFM基因;bh1D在21.15%的人群中存在. 具有更多毒性因子的菌株在小鼠模型中显示病原性增加.
结论:
- B. cereus 是内蒙古乳牛群中一个新兴的毒性病原体,导致牛乳炎.
- 对抗微生物药物的管理和对毒性因素的监测对于有效的乳腺炎管理至关重要.
- 这项研究的流行病学数据可以指导兽医实践和干预策略.
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