细菌存活率低于零:储存时间对公牛精液中的细菌生存能力的影响
Aleksandar Cojkic1, Ingrid Hansson2, Jane M Morrell1
1Department of Clinical Sciences, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden.
Cryobiology
|March 20, 2025
概括
冷保存保持了公牛精液中的总细菌数量,但改变了个体细菌物种的生存率. 存储时间会影响细菌的持续存在,影响对原样的准确评估.
科学领域:
- 兽医微生物学 兽医微生物学
- 低温生物学 低温生物学
- 牛的繁殖 牛的繁殖
背景情况:
- 精子冷保存技术已经很成熟,但它们对精液中的细菌生存能力的影响基本上没有特征.
- 精液中的细菌种群的准确评估对于生殖健康和牲畜疾病控制至关重要.
研究的目的:
- 研究冷保存和储存时间对公牛精液中的细菌群和物种存活率的影响.
- 为了确定在冷和长期储存在-80°C后,细菌负荷和组成是否发生变化.
主要方法:
- 在冷保存之前,采集并分析牛精液样本以进行细菌计数和物种识别 (使用矩阵辅助激光消化离子化-飞行质谱的时间).
- 样品用糖醇冷保存,并在-80°C下保存6天和13天.
- 在每一个时间点解后,细菌种群被重新定量,物种被重新识别.
主要成果:
- 在所有储存时间内,新鲜和冷保存的精液样本之间的总细菌计数保持一致.
- 总共有31种细菌物种被确定,在储存6天和13天后观察到物种存在的变化.
- 在整个研究过程中,有10种细菌物种持续存在,而其他物种则基于储存时间的差异性生存率.
结论:
- 冷保存不会显著改变公牛精液中的总体细菌负载.
- 精液中的细菌群落的组成受冷保存和储存时间的影响,影响特定物种的生存.
- 培养解精液可能不完全代表原始细菌特征,因此需要进一步研究冷样本中最佳细菌评估方法.
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