Laboratory of Probiogenomics, Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11a, 43124 Parma, Italy.
Department of Medical-Veterinary Science, University of Parma, Strada del Taglio 10, 43126 Parma, Italy.
FEMS Microbiol Ecol. 2023 Nov 13;99(12). doi: 10.1093/femsec/fiad136.
Subclinical mastitis is one of the most widespread diseases affecting dairy herds with detrimental effects on animal health, milk productivity, and quality. Despite its multifactorial nature, the presence of pathogenic bacteria is regarded one of the main drivers of subclinical mastitis, causing a disruption of the homeostasis of the bovine milk microbial community. However, bovine milk microbiota alterations associated with subclinical mastitis still represents a largely unexplored research area. Therefore, the species-level milk microbiota of a total of 75 milk samples, collected from both healthy and subclinical mastitis-affected cows from two different stables, was deeply profiled through an ITS, rather than a traditional, and less informative, 16S rRNA gene microbial profiling. Surprisingly, the present pilot study not only revealed that subclinical mastitis is characterized by a reduced biodiversity of the bovine milk microbiota, but also that this disease does not induce standard alterations of the milk microbial community across stables. In addition, a flow cytometry-based total bacterial cell enumeration highlighted that subclinical mastitis is accompanied by a significant increment in the number of milk microbial cells. Furthermore, the combination of the metagenomic and flow cytometry approaches allowed to identify different potential microbial marker strictly correlated with subclinical mastitis across stables.
隐性乳腺炎是影响奶牛群的最广泛疾病之一，对动物健康、牛奶产量和质量都有不利影响。尽管其具有多因素性质，但致病性细菌的存在被认为是隐性乳腺炎的主要驱动因素之一，导致奶牛乳微生物群落的内稳态被破坏。然而，与隐性乳腺炎相关的奶牛乳微生物群的改变仍然是一个很大程度上尚未探索的研究领域。因此，通过 ITS 而不是传统的、信息量较少的 16S rRNA 基因微生物分析，对来自两个不同牛棚的健康和隐性乳腺炎奶牛的总共 75 个牛奶样本的物种水平乳微生物群进行了深入分析。令人惊讶的是，本初步研究不仅表明隐性乳腺炎的特征是奶牛乳微生物群的生物多样性降低，而且这种疾病不会在牛棚之间引起乳微生物群落的标准改变。此外，基于流式细胞术的总细菌细胞计数强调，隐性乳腺炎伴随着乳微生物细胞数量的显著增加。此外，宏基因组学和流式细胞术方法的结合允许确定与牛棚之间的隐性乳腺炎严格相关的不同潜在微生物标记物。
