Project description:White-lipped deer (Cervus albirostris) is a nationally protected wild animal species in China, as well as a unique and endangered species, according to the International Union for Conservation of Nature (IUCN) Red List. Captivity may alleviate the pressure from poaching and contribute to the repopulation and conservation of the population in the wild. The gut microbiota is described as a complex, interactive internal system that has effects on diseases of the host, with many interactions. However, the influence of captivity on the composition and assembly process of gut microbiota in white-lipped deer is unclear. This study applied high-throughput 16S rRNA sequencing technology to determine differences in the gut microbiota between captive (CW) and wild (WW) white-lipped deer. We used the null model, neutral community model, and niche width to identify whether captivity affects the composition and assembly process of gut microbiota. The results show that WW has a higher number of Firmicutes and a lower number of Bacteroidetes compared with CW at the phylum level, and it has more opportunistic pathogens and specific decomposition bacteria at the genus level. Principal coordinate analysis also indicated significant differences in the composition and function of gut microbiota in CW and WW. Moreover, the results reveal that captivity shifts the ecological assembly process of gut microbiota by raising the contribution of deterministic processes. In conclusion, our results demonstrate that captivity might potentially have an unfavorable effect on white-lipped deer by continually exerting selective pressure.
Project description:Climate change is rapidly affecting species distributions across the globe, particularly in the North Atlantic. For highly mobile and elusive cetaceans, the genetic data needed to understand population dynamics are often scarce. Cold-water obligate species such as the white-beaked dolphin (Lagenorhynchus albirostris) face pressures from habitat shifts due to rising sea surface temperatures in addition to other direct anthropogenic threats. Unravelling the genetic connectivity between white-beaked dolphins across their range is needed to understand the extent to which climate change and anthropogenic pressures may impact species-wide genetic diversity and identify ways to protect remaining habitat. We address this by performing a population genomic assessment of white-beaked dolphins using samples from much of their contemporary range. We show that the species displays significant population structure across the North Atlantic at multiple scales. Analysis of contemporary migration rates suggests a remarkably high connectivity between populations in the western North Atlantic, Iceland and the Barents Sea, while two regional populations in the North Sea and adjacent UK and Irish waters are highly differentiated from all other clades. Our results have important implications for the conservation of white-beaked dolphins by providing guidance for the delineation of more appropriate management units and highlighting the risk that local extirpation may have on species-wide genetic diversity. In a broader context, this study highlights the importance of understanding genetic structure of all species threatened with climate change-driven range shifts to assess the risk of loss of species-wide genetic diversity.
Project description:The gut microbiota has key physiological functions in host adaptation, although little is known about the seasonal changes in the composition and diversity of the gut microbiota in deer. In this study, seasonal variations (grassy and withering season) in the gut microbiota of white-lipped deer (Cervus albirostris), which lives in alpine environments, were explored through 16S rRNA high-throughput sequencing based on sixteen fecal samples collected from Gansu Qilian Mountain National Nature Reserve in China. At the phylum level, Firmicutes, Bacteroidota, and Actinobacteriota dominated the grassy season, while Firmicutes, Proteobacteria, and Actinobacteriota dominated the withering season. At the genus level, Carnobacterium dominated the grassy season, while Arthrobacter and Acinetobacter dominated the withering season. Alpha diversity results (Shannon: P = 0.01, ACE: P = 0.00, Chao1: P = 0.00) indicated that there was a difference in the diversity and richness of the gut microbiota between the two seasons, with higher diversity in the grassy season than in the withering season. Beta diversity results further indicated that there was a significant difference in the community structure between the two seasons (P = 0.001). In summary, the composition, diversity, and community structure of the gut microbiota showed significant seasonal variations, which could be explained by variations in the seasonal food availability, composition, diversity, and nutrition due to phenological alternations. The results of this study indicate that the gut microbiota can adapt to changes in the environment and provide the scientific basis for health assessment of white-lipped deer.