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Applied and environmental microbiology2012; 78(8); 2522-2532; doi: 10.1128/AEM.06252-11

Equine stomachs harbor an abundant and diverse mucosal microbiota.

Abstract: Little is known about the gastric mucosal microbiota in healthy horses, and its role in gastric disease has not been critically examined. The present study used a combination of 16S rRNA bacterial tag-encoded pyrosequencing (bTEFAP) and fluorescence in situ hybridization (FISH) to characterize the composition and spatial distribution of selected gastric mucosal microbiota of healthy horses. Biopsy specimens of the squamous, glandular, antral, and any ulcerated mucosa were obtained from 6 healthy horses by gastroscopy and from 3 horses immediately postmortem. Pyrosequencing was performed on biopsy specimens from 6 of the horses and yielded 53,920 reads in total, with 631 to 4,345 reads in each region per horse. The microbiome segregated into two distinct clusters comprised of horses that were stabled, fed hay, and sampled at postmortem (cluster 1) and horses that were pastured on grass, fed hay, and biopsied gastroscopically after a 12-h fast (cluster 2). The types of bacteria obtained from different anatomic regions clustered by horse rather than region. The dominant bacteria in cluster 1 were Firmicutes (>83% reads/sample), mainly Streptococcus spp., Lactobacillus spp. and, Sarcina spp. Cluster 2 was more diverse, with predominantly Proteobacteria, Bacteroidetes, and Firmicutes, consisting of Actinobacillus spp. Moraxella spp., Prevotella spp., and Porphyromonas spp. Helicobacter sp. sequences were not identified in any of 53,920 reads. FISH (n = 9) revealed bacteria throughout the stomach in close apposition to the mucosa, with significantly more Streptococcus spp. present in the glandular region of the stomach. The equine stomach harbors an abundant and diverse mucosal microbiota that varies by individual.
Publication Date: 2012-02-03 PubMed ID: 22307294PubMed Central: PMC3318809DOI: 10.1128/AEM.06252-11Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research aimed to understand the gastric mucosal microbiota in healthy horses, their diversity, and how they may influence stomach diseases. The study used techniques like bTEFAP and FISH to determine the microbiome composition and spatial distribution on horse stomach lining. The results showed two separate categories of microbiota based on horse lifestyle and diet, with differences in predominant bacteria types.

Overview of Research Methods

  • The process used 16S rRNA bacterial tag-encoded pyrosequencing (bTEFAP) and fluorescence in situ hybridization (FISH) to analyze the gastric mucosal microbiota in the horses.
  • A total of 6 healthy horses were sampled by gastroscopy, and 3 horses were examined postmortem.
  • The study considered the squamous, glandular, antral, and any ulcerated mucosa to gather biopsy specimens from the examined horses.

Key Findings

  • The microbiome in horses displayed two distinct clusters, which were likely a result of different lifestyles and diets.
  • The first cluster included horses that were stabled, fed hay, and sampled postmortem. This cluster predominantly contained Firmicutes bacteria (>83% reads/sample), mainly Streptococcus spp., Lactobacillus spp., and Sarcina spp.
  • The second cluster was associated with pastured horses on grass, fed hay, and biopsied gastroscopically after a 12-hour fast. This group had a diverse microbiota, with mainly Proteobacteria, Bacteroidetes, and Firmicutes, consisting of Actinobacillus spp., Moraxella spp., Prevotella spp., and Porphyromonas spp.
  • Interestingly, no Helicobacter sp. sequences were identified in any of the 53,920 reads, an observation that could provide information regarding gastric health and disease prevalence in horses.
  • With the help of FISH, the study also discovered that the bacteria were present throughout the stomach near the mucosa, with a significant presence of Streptococcus spp. in the glandular region of the stomach.

Implications

  • Findings from this study indicate the horse gastric system contains a diverse mucosal microbiota. The diversity appears to be significantly influenced by the animal’s lifestyle and diet.
  • By understanding the presence and diversity of gastric microbiota in horses, veterinarians and researchers can gain further insights into gastric diseases and potential prevention strategies or treatments.
  • The absence of Helicobacter sp. bacteria could suggest a possible correlation between this bacterium and disease presence, warranting further research.

Cite This Article

APA
Perkins GA, den Bakker HC, Burton AJ, Erb HN, McDonough SP, McDonough PL, Parker J, Rosenthal RL, Wiedmann M, Dowd SE, Simpson KW. (2012). Equine stomachs harbor an abundant and diverse mucosal microbiota. Appl Environ Microbiol, 78(8), 2522-2532. https://doi.org/10.1128/AEM.06252-11

Publication

ISSN: 1098-5336
NlmUniqueID: 7605801
Country: United States
Language: English
Volume: 78
Issue: 8
Pages: 2522-2532

Researcher Affiliations

Perkins, G A
  • Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
den Bakker, H C
    Burton, A J
      Erb, H N
        McDonough, S P
          McDonough, P L
            Parker, J
              Rosenthal, R L
                Wiedmann, M
                  Dowd, S E
                    Simpson, K W

                      MeSH Terms

                      • Animals
                      • Bacteria / classification
                      • Bacteria / genetics
                      • Biodiversity
                      • Biopsy
                      • Cluster Analysis
                      • DNA, Bacterial / chemistry
                      • DNA, Bacterial / genetics
                      • DNA, Ribosomal / chemistry
                      • DNA, Ribosomal / genetics
                      • Gastric Mucosa / microbiology
                      • Horses / microbiology
                      • In Situ Hybridization, Fluorescence
                      • Metagenome
                      • Molecular Sequence Data
                      • Phylogeny
                      • RNA, Ribosomal, 16S / genetics
                      • Sequence Analysis, DNA
                      • Stomach / microbiology

                      Grant Funding

                      • Wellcome Trust
                      • T32 AI070077 / NIAID NIH HHS

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