Microbial communities in swine lungs and their association with lung lesions

Abstract

Summary Under natural farming, environmental pathogenic microorganisms may invade and affect swine lungs, further resulting in lung lesions. However, few studies on swine lung microbiota and their potential relationship with lung lesions were reported. Here, we sampled 20 pigs from a hybrid herd raised under natural conditions; we recorded a lung‐lesion phenotype and investigated lung microbial communities by sequencing the V3‐V4 region of 16S rRNA gene for each individual. We found reduced microbial diversity but more biomass in the severe‐lesion lungs. Methylotenera , Prevotella , Sphingobium and Lactobacillus were the prominent bacteria in the healthy lungs, while Mycoplasma , Ureaplasma , Sphingobium , Haemophilus and Phyllobacterium were the most abundant microbes in the severe‐lesion lungs. Notably, we identified 64 lung‐lesion‐associated OTU s, of which two classified to Mycoplasma were positively associated with lung lesions and 62 showed negative association including thirteen classified to Prevotella and six to Ruminococcus . Cross‐validation analysis showed that lung microbiota explained 23.7% phenotypic variance of lung lesions, suggesting that lung microbiota had large effects on promoting lung healthy. Furthermore, 22 KEGG pathways correlated with lung lesions were predicted. Altogether, our findings improve the knowledge about swine lung microbial communities and give insights into the relationship between lung microbiota and lung lesions.

A survey of an eight-breed cross swine heterogeneous population demonstrates the associations among immune cell traits, lung lesions and Mycoplasma abundances

“…Previously, we found that Mycoplasma was the most abundant and only bacteria signi cantly associated with lung lesions in pigs (3). Similarly, we found that the pattern of correlations of Mycoplasma with six hematological parameters including RDW-SD, NLR, NEUR, LYMR, MCHC, and LYM was similar to the lung lesion correlations.…”

“…The amplicons were then puri ed and sequenced on an Illumina MiSeq sequencing platform (Illumina, SanDiego, CA, USA). The raw sequence reads were ltered as previously described (3). The Operational taxonomic units (OTUs) were clustered using UCLUST cluster algorithm in USEARCH v7.01090 (8).…”

“…Enzootic pneumonia in pigs is a type of respiratory disease links to infection of pathogenic bacteria such as Mycoplasma pneumoniae and accompanies with development of lung lesions (2). The lung tissue of pigs is accessible at slaughter, which allows for direct evaluation of lung lesions and quanti cation of lung microbiota or viruses from bronchoalveolar lavage through serological tests, PCR, or sequencing technology (3,4). For example, a study of 125 farrow pigs found that Mycoplasma hyopneumoniae, porcine reproductive and respiratory syndrome virus, and swine in uenza viruses are the major pathogens involved in the development of pneumonia-like lung lesions (4).…”

“…For example, a study of 125 farrow pigs found that Mycoplasma hyopneumoniae, porcine reproductive and respiratory syndrome virus, and swine in uenza viruses are the major pathogens involved in the development of pneumonia-like lung lesions (4). We measured microbial communities from 20 lung samples with extreme lung lesion phenotypes from a pig heterogeneous population derived from eight founder breeds, and found that Mycoplasma is the major pathogen associated with the severity of lung lesions and signi cantly affect the growth performance of pigs (3).…”

Microbiomes as the new keystone for life sciences development

“…The methodology employed in all these studies, however, remains largely the same regardless of the host. Interesting examples of non‐human microbial population studies are the works recently published in Microbial Biotechnology highlighting the implication of the imbalance of microbial flora from different anatomic sites with lesions and diseases (Huang et al ., ), or the relatedness between changes in diet with changes in the microbiome in different species (Simons et al ., ; Walburn et al ., ). As stated above, linking changes in microbial communities with human diseases is a hot spot in microbial population studies.…”