Porcellato Davide, Smistad Marit, Bombelli Alberto, Abdelghani Ahmed, Jørgensen Hannah Joan, Skeie Siv B
Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NMBU, Ås, Norway.
Norwegian Veterinary Institute, Oslo, Norway.
Front Microbiol. 2021 Feb 23;12:616429. doi: 10.3389/fmicb.2021.616429. eCollection 2021.
Introduction of microbial contaminations in the dairy value chain starts at the farm level and the initial microbial composition may severely affect the production of high-quality dairy products. Therefore, understanding the farm-to-farm variation and longitudinal shifts in the composition of the bulk tank milk microbiota is fundamental to increase the quality and reduce the spoilage and waste of milk and dairy products. In this study, we performed a double experiment to study long- and short-term longitudinal shifts in microbial composition using 16S rRNA gene amplicon sequencing. We analyzed milk from 37 farms, that had also been investigated two years earlier, to understand the stability and overall microbial changes over a longer time span. In addition, we sampled bulk tank milk from five farms every 1-2 weeks for up to 7 months to observe short-term changes in microbial composition. We demonstrated that a persistent and farm-specific microbiota is found in bulk tank milk and that changes in composition within the same farm are mostly driven by bacterial genera associated with mastitis (e.g., and ). On a long-term, we detected that major shift in milk microbiota were not correlated with farm settings, such as milking system, number of cows and quality of the milk but other factors, such as weather and feeding, may have had a greater impact on the main shifts in composition of the bulk tank milk microbiota. Our results provide new information regarding the ecology of raw milk microbiota at the farm level.
乳制品价值链中微生物污染的引入始于农场层面，初始微生物组成可能会严重影响高品质乳制品的生产。因此，了解大罐牛奶微生物群组成在农场间的差异和纵向变化，对于提高牛奶和乳制品的质量、减少变质和浪费至关重要。在本研究中，我们进行了一项双重实验，使用16S rRNA基因扩增子测序来研究微生物组成的长期和短期纵向变化。我们分析了37个农场的牛奶，这些农场在两年前也进行过调查，以了解更长时间跨度内的稳定性和整体微生物变化。此外，我们每隔1 - 2周从五个农场采集大罐牛奶样本，持续7个月，以观察微生物组成的短期变化。我们证明，在大罐牛奶中发现了持续存在且特定于农场的微生物群，并且同一农场内的组成变化主要由与乳腺炎相关的细菌属驱动（例如，和）。从长期来看我们检测到，牛奶微生物群的主要变化与农场设置无关，如挤奶系统、奶牛数量和牛奶质量，而其他因素，如天气和饲养，可能对大罐牛奶微生物群组成的主要变化有更大影响。我们的结果提供了有关农场层面生鲜乳微生物群生态学的新信息。
