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BMC veterinary research2012; 8; 231; doi: 10.1186/1746-6148-8-231

Pyrosequencing of 16S rRNA genes in fecal samples reveals high diversity of hindgut microflora in horses and potential links to chronic laminitis.

Abstract: The nutrition and health of horses is closely tied to their gastrointestinal microflora. Gut bacteria break down plant structural carbohydrates and produce volatile fatty acids, which are a major source of energy for horses. Bacterial communities are also essential for maintaining gut homeostasis and have been hypothesized to contribute to various diseases including laminitis. We performed pyrosequencing of 16S rRNA bacterial genes isolated from fecal material to characterize hindgut bacterial communities in healthy horses and those with chronic laminitis. Results: Fecal samples were collected from 10 normal horses and 8 horses with chronic laminitis. Genomic DNA was extracted and the V4-V5 segment of the 16S rRNA gene was PCR amplified and sequenced on the 454 platform generating a mean of 2,425 reads per sample after quality trimming. The bacterial communities were dominated by Firmicutes (69.21% control, 56.72% laminitis) and Verrucomicrobia (18.13% control, 27.63% laminitis), followed by Bacteroidetes, Proteobacteria, and Spirochaetes. We observed more OTUs per individual in the laminitis group than the control group (419.6 and 355.2, respectively, P = 0.019) along with a difference in the abundance of two unassigned Clostridiales genera (P = 0.03 and P = 0.01). The most abundant bacteria were Streptococcus spp., Clostridium spp., and Treponema spp.; along with unassigned genera from Subdivision 5 of Verrucomicrobia, Ruminococcaceae, and Clostridiaceae, which together constituted ~ 80% of all OTUs. There was a high level of individual variation across all taxonomic ranks. Conclusions: Our exploration of the equine fecal microflora revealed higher bacterial diversity in horses with chronic laminitis and identification of two Clostridiales genera that differed in abundance from control horses. There was large individual variation in bacterial communities that was not explained in our study. The core hindgut microflora was dominated by Streptococcus spp., several cellulytic genera, and a large proportion of uncharacterized OTUs that warrant further investigation regarding their function. Our data provide a foundation for future investigations of hindgut bacterial factors that may influence the development and progression of chronic laminitis.
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Publication Date: 2012-11-27 PubMed ID: 23186268PubMed Central: PMC3538718DOI: 10.1186/1746-6148-8-231Google Scholar: Lookup
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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 article is about the comprehensive study of the diversity of gut microflora in horses, highlighting the links between bacterial diversity and chronic laminitis, a common disease in horses. This was done through pyrosequencing of 16S rRNA bacterial genes isolated from fecal samples of both healthy horses and those with chronic laminitis.

Research Methodology

  • The researchers collected fecal samples from 10 healthy horses and 8 horses suffering from chronic laminitis, a painful condition affecting the horse’s hooves.
  • They extracted genomic DNA and amplified and sequenced the V4-V5 segment of the 16S rRNA gene, using the 454 platform. This gene is known to provide valuable information on bacterial species present in the samples.
  • The sequencing generated an average of 2,425 reads per sample after quality trimming, which provided the researchers with a great amount of data for their analysis.

Results and Observations

  • Most prevalent bacterial communities were Firmicutes (69.21% in healthy horses, 56.72% in laminitis-affected horses) and Verrucomicrobia (18.13% in healthy, 27.63% in chronically affected horses). Other detected bacterias included Bacteroidetes, Proteobacteria, and Spirochaetes.
  • The study revealed greater bacterial diversity in horses suffering from chronic laminitis, with more OTUs (operational taxonomic units) per individual compared to healthy horses.
  • The dominant bacteria were Streptococcus spp., Clostridium spp., and Treponema spp. Unassigned bacteria from Subdivision 5 of Verrucomicrobia, Ruminococcaceae, and Clostridiaceae constituted approximately 80% of all OTUs.
  • A significant difference was noted in the abundance of two unassigned Clostridiales genera between the healthy and laminitis-affected horses.
  • There was a high level of individual variation across all taxonomic ranks.

Conclusions

  • The research offers new insights into the higher bacterial diversity in horses with chronic laminitis. It also identifies two Clostridiales genera that differ in abundance in horses with laminitis compared to healthy horses.
  • Although individual variation in bacterial communities was significant and unexplained, the core hindgut microflora was dominated by specific bacteria including Streptococcus spp., several cellulytic genera, and a vast proportion of uncharacterized OTUs that need further investigation.
  • This study lays a foundation for further exploration of bacterial factors that can influence the progression of chronic laminitis in horses.

Cite This Article

APA
Steelman SM, Chowdhary BP, Dowd S, Suchodolski J, Janečka JE. (2012). Pyrosequencing of 16S rRNA genes in fecal samples reveals high diversity of hindgut microflora in horses and potential links to chronic laminitis. BMC Vet Res, 8, 231. https://doi.org/10.1186/1746-6148-8-231

Publication

BMC veterinary research
ISSN: 1746-6148
NlmUniqueID: 101249759
Country: England
Language: English
Volume: 8
Pages: 231

Researcher Affiliations

Steelman, Samantha M
  • Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA.
Chowdhary, Bhanu P
    Dowd, Scot
      Suchodolski, Jan
        Janečka, Jan E

          MeSH Terms

          • Animals
          • Bacteria / classification
          • Chronic Disease
          • DNA, Bacterial / genetics
          • Foot Diseases / pathology
          • Foot Diseases / veterinary
          • Gastrointestinal Tract / microbiology
          • Genetic Variation
          • Hoof and Claw / pathology
          • Horse Diseases / microbiology
          • Horses
          • Nucleic Acid Amplification Techniques
          • RNA, Bacterial / genetics
          • RNA, Ribosomal, 16S / genetics
          • Species Specificity

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