Community Composition and Diversity of Intestinal Microbiota in Captive and Reintroduced Przewalski’s Horse (Equus ferus przewalskii)

Abstract

Large and complex intestinal microbiota communities in hosts have profound effects on digestion and metabolism. To better understand the community structure of intestinal microbiota in Przewalski’s horse ( Equus ferus przewalskii ) under different feeding regimes, we compared bacterial diversity and composition between captive and reintroduced Przewalski’s horses, using high-throughput 16S-rRNA gene sequencing for identification. Reintroduced Przewalski’s horses were sampled in two Chinese nature reserves, i.e., Dunhuang Xihu Nature Reserve (DXNR; n = 8) in Gansu Province and Kalamaili Nature Reserve (KNR; n = 12) in Xinjiang Province, and compared to a captive population at the Przewalski’s Horse Breeding Center in Xinjiang (PHBC; n = 11). The composition of intestinal microbiota in Przewalski’s horses was significantly different at the three study sites. Observed species was lowest in DXNR, but highest in KNR. Lowest Shannon diversity was observed in DXNR, while in KNR and PHBC had a moderately high diversity; Simpson diversity showed an opposite trend compared with the Shannon index. Linear Discriminant Analysis effect size was used to determine differentially distributed bacterial taxa at each study site. The most dominant phyla of intestinal microbiota were similar in all feeding regimes, including mainly Firmicutes, Bacteroidetes, Verrucomicrobia, and Spirochaetes. Differing abundances of intestinal microbiota in Przewalski’s horses may be related to different food types at each study site, differences in diversity may be attributed to low quality food in DXNR. Results indicated that diet is one of the important factors that can influence the structure of intestinal microbiota communities in Przewalski’s horse. These findings combined with a detailed knowledge of the available and consumed food plant species could provide guidelines for the selection of potential future reintroduction sites.

Gut Microbiomes of Endangered Przewalski’s Horse Populations in Short- and Long-Term Captivity: Implication for Species Reintroduction Based on the Soft-Release Strategy

“…We observed more OTUs than reported by the previous study in the same area (Li et al, 2019), which may be the result of the different DNA extraction method. Unlike the previous study, we extracted DNA from the fresh sample directly and hence have likely avoided the potential bias caused by storage.…”

“…In particular, diet is a major contributor to gut microbial variation (Muegge et al, 2011;Li et al, 2013;Amato et al, 2015;Carmody et al, 2015). Previous studies have revealed a decreased bacterial diversity in captive PH, which is likely due to shift in diet (Li et al, 2019). A key issue, then, is whether the hosts have the ability to retain diverse bacteria when confined for a short-term.…”

“…In most comparative studies, captive and wild members of a species often live in different habitats. For example, previous studies showed that gut bacteria in PH form a distinct, more diverse community than those in domestic horses (Mckenzie et al, 2017;Metcalf et al, 2017) and captive PH (Li et al, 2019), but the influence of environmental change (e.g., diet) was not excluded. Thus, these studies could not determine whether the reduced bacterial diversity in captivity is due to decreased contact with varying diets and environmental substrates (e.g., soil and aquatic systems) that can transmit transient bacteria (Kohl and Dearing, 2014;Mckenzie et al, 2017) or changes in host physiology under captivity.…”

Dramatic shifts in intestinal fungal community between wintering Hooded Crane and Domestic Goose

“…The wild food resources exhibit lower nutrient contents relative to paddy. Therefore, the higher intestinal fungal diversity might benefit wintering Hooded Cranes to efficiently acquire nutrients from indigestible food (Cantarel et al 2012;Li et al 2019).…”

Effect of host breeds on gut microbiome and serum metabolome in meat rabbits

“…1 b-d). Earlier studies have highlighted these microbial diversity indices vary greatly in different pig, chicken, and horse breeds [ 4 , 5 , 17 ].…”