School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, Brazil.
Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Vet Res. 2022 Mar 18;53(1):20. doi: 10.1186/s13567-022-01038-9.
Mycoplasma (M.) hyopneumoniae interacts with the respiratory microbiota and facilitates colonization of other pathogens. The present study investigated the pulmonary and nasal microbiota of M. hyopneumoniae-infected and M. hyopneumoniae-free pigs. Sixty-six pigs from three commercial herds were selected at the end of the finishing phase: 44 originated from two M. hyopneumoniae-positive herds and 22 from a M. hyopneumoniae-negative farm. At the slaughterhouse, samples of nasal turbinate (NT) and bronchus-alveolar lavage fluid (BALF) were collected. DNA was extracted with a commercial kit and the infection status was confirmed by qPCR. All samples from the same herd were pooled, and next-generation sequencing based on the hypervariable region V3-V4 of the 16 s bacterial rDNA was performed. Data analysis included the taxonomic analysis, Alpha diversity indexes, and Principal coordinates analysis (Pcoa) using Jaccard, Bray-Curtis, Weighted Unifrac, and Unweighted Unifrac distances. All pigs from the infected herds tested PCR positive for M. hyopneumoniae, whereas all pigs from the negative farm were negative. There was a greater diversity of microorganisms in BALF when compared to NT samples in all the farms. BALF samples from infected animals showed higher abundance of M. hyopneumoniae than NT samples and a predominance of Pasteurella multocida among the main species identified, which was also abundant in the M. hyopneumoniae-free herd. PCoa diagrams indicated that for most of the samples, dissimilarity on bacterial composition was observed, regardless of infection status and sample type. Therefore, the lung microbiota was modulated by M. hyopneumoniae infection, which could play a role in the pathogenesis of M. hyopneumoniae-disease.
猪肺炎支原体（M. hyopneumoniae）与呼吸道微生物群相互作用，促进其他病原体的定植。本研究调查了感染和未感染 M. hyopneumoniae 的猪的肺部和鼻腔微生物群。从三个商业养殖场中选择了 66 头肥育期末的猪：44 头来自两个 M. hyopneumoniae 阳性养殖场，22 头来自一个 M. hyopneumoniae 阴性农场。在屠宰场，收集鼻甲骨（NT）和支气管肺泡灌洗液（BALF）样本。使用商业试剂盒提取 DNA，并通过 qPCR 确认感染状态。同一养殖场的所有样本均混合，然后对 16s 细菌 rDNA 的高变区 V3-V4 进行基于下一代测序的分析。数据分析包括分类分析、Alpha 多样性指数以及使用 Jaccard、Bray-Curtis、Weighted Unifrac 和 Unweighted Unifrac 距离的主坐标分析（Pcoa）。来自感染养殖场的所有猪均经 PCR 检测 M. hyopneumoniae 阳性，而来自阴性农场的所有猪均为阴性。与所有农场的 NT 样本相比，BALF 样本中的微生物多样性更大。与 NT 样本相比，感染动物的 BALF 样本中 M. hyopneumoniae 的丰度更高，并且在主要鉴定的物种中，巴氏杆菌属的丰度更高，在 M. hyopneumoniae 阴性养殖场中也很丰富。Pcoa 图谱表明，对于大多数样本，无论感染状态和样本类型如何，细菌组成的差异均明显。因此，肺部微生物群被 M. hyopneumoniae 感染所调节，这可能在 M. hyopneumoniae 疾病的发病机制中发挥作用。
