Unraveling the distinctive gut microbiome of khulans (Equus hemionus hemionus) in comparison to their drinking water and closely related equids.
Abstract: The microbial composition of host-associated microbiomes is influenced by co-evolutionary interactions, host genetics, domestication, and the environment. This study investigates the contribution of environmental microbiota from freshwater bodies to the gastrointestinal microbiomes of wild khulans (Equus hemionus hemionus, n = 21) and compares them with those of captive khulans (n = 12) and other equids-Przewalski's horse (n = 82) and domestic horse (n = 26). Using PacBio technology and the LotuS pipeline for 16S rRNA gene sequencing, we analyze microbial diversity and conduct differential abundance, alpha, and beta diversity analyses. Results indicate limited microbial sharing between wild khulans and their waterhole environments, suggesting minimal environmental influence on their gut microbiomes and low levels of water contamination by khulans. Wild khulans exhibit greater microbial diversity and richness compared to captive ones, likely due to adaptations to the harsh nutritional conditions of the Gobi desert. Conversely, captive khulans show reduced microbial diversity, potentially affected by dietary changes during captivity. These findings highlight the significant impact of environment and lifestyle on the gut microbiomes of equids.
© 2025. The Author(s).
Publication Date: 2025-01-22 PubMed ID: 39843625PubMed Central: PMC11754619DOI: 10.1038/s41598-025-87216-zGoogle Scholar: Lookup
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- Journal Article
- Comparative Study
- Research Support
- Non-U.S. Gov't
Summary
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This research article discusses a study into the impact of environmental factors on the gut microbiomes of khulans, a type of wild ass, by comparing the microbiomes of wild and captive khulans and other equids to their water sources. The findings suggest a limited influence of the environmental microbiota on the khulan gut microbiome, but do highlight significant effects related to captivity and diet changes.
Comparative Analysis of Gut Microbiomes
- The researchers carried out comparative analysis of gut microbiomes among different types of equids, including wild khulans, captive khulans, Przewalski’s horses (another type of wild horse), and domestic horses.
- For this comparative study, a total of 21 wild khulans, 12 captive khulans, 82 Przewalski’s horses, and 26 domestic horses were used.
- The microbial composition of the gut was examined using PacBio technology and the LotuS pipeline for 16S rRNA gene sequencing.
- This gene sequencing technology provided data on the broad microbial diversity present in each of the groups, allowing for comparison.
Interactions with Environment
- The researchers also investigated how interaction with the environment, specifically drinking water, influenced the gut microbiome.
- By comparing the gut microbiota with those found in the freshwater bodies that the khulans drink from, the researchers could determine the level of microbial sharing, if any.
- The results found that there was limited microbial sharing between the wild khulans and their water sources, indicating that drinking water might not play a significant role in shaping their gut microbiome.
- It also suggested low levels of water contamination caused by the khulans, meaning that direct transmission of bacteria through fecal matter into the water was minimal.
Diet and Lifestyle
- The comparison between wild and captive khulan gut microbiomes provided insights into how diet and environmental changes influence the microbial diversity in the gut.
- Wild khulans displayed a higher level of microbial diversity, possibly due to their adaptation to the harsh nutritional conditions in the Gobi Desert.
- Conversely, captive khulans showed reduced microbial diversity; the authors suggest that this is potentially due to changes in their diet during captivity.
- Thus, the results highlighted the overall significant impact of diet and lifestyle on the gut microbiomes of these creatures.
Cite This Article
APA
Jarquín-Díaz VH, Dayaram A, Soilemetzidou ES, Desvars-Larrive A, Bohner J, Buuveibaatar B, Kaczensky P, Walzer C, Greenwood AD, Löber U.
(2025).
Unraveling the distinctive gut microbiome of khulans (Equus hemionus hemionus) in comparison to their drinking water and closely related equids.
Sci Rep, 15(1), 2767.
https://doi.org/10.1038/s41598-025-87216-z Publication
Researcher Affiliations
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Alfred- Kowalke Str. 17, 10315, Berlin, Germany.
- Experimental and Clinical Research Center, a cooperation between the Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association and the Charité - Universitätsmedizin Berlin, Berlin, Germany.
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
- Charité - Universitätsmedizin Berlin, AG Rosenmund, Charitéplatz 1, 10117, Berlin, Germany.
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Austria.
- Unit of Veterinary Public Health and Epidemiology, Complexity Science Hub, University of Veterinary Medicine, Vienna, Austria.
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
- Wildlife Conservation Society, Mongolia Program, Ulaanbaatar, Mongolia.
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Austria.
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Stor-Elvdal, Norway.
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Austria.
- Wildlife Conservation Society - Global USA and University of Veterinary Medicine AT, New York, USA.
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. greenwood@izw-berlin.de.
- School of Veterinary Medicine, Free University of Berlin, Oertzenweg 19 b, 14163, Berlin, Germany. greenwood@izw-berlin.de.
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Alfred- Kowalke Str. 17, 10315, Berlin, Germany. Ulrike.Loeber@mdc-berlin.de.
- Experimental and Clinical Research Center, a cooperation between the Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association and the Charité - Universitätsmedizin Berlin, Berlin, Germany. Ulrike.Loeber@mdc-berlin.de.
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. Ulrike.Loeber@mdc-berlin.de.
MeSH Terms
- Animals
- Gastrointestinal Microbiome / genetics
- RNA, Ribosomal, 16S / genetics
- Equidae / microbiology
- Drinking Water / microbiology
- Bacteria / genetics
- Bacteria / classification
- Horses / microbiology
Conflict of Interest Statement
Declarations. Competing interests: The authors declare no competing interests.
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