Comparing the gut microbiota of Sichuan golden monkeys across multiple captive and wild settings: roles of anthropogenic activities and host factors.

BACKGROUND: Captivity and artificial food provision are common conservation strategies for the endangered golden snub-nosed monkey (Rhinopithecus roxellana). Anthropogenic activities have been reported to impact the fitness of R. roxellana by altering their gut microbiota, a crucial indicator of animal health. Nevertheless, the degree of divergence in gut microbiota between different anthropogenically-disturbed (AD) R. roxellana and their counterparts in the wild has yet to be elucidated. Here, we conducted a comparative analysis of the gut microbiota across nine populations of R. roxellana spanning China, which included seven captive populations, one wild population, and another wild population subject to artificial food provision. RESULTS: Both captivity and food provision significantly altered the gut microbiota. AD populations exhibited common variations, such as increased Bacteroidetes and decreased Firmicutes (e.g., Ruminococcus), Actinobacteria (e.g., Parvibacter), Verrucomicrobia (e.g., Akkermansia), and Tenericutes. Additionally, a reduced Firmicutes/Bacteroidetes ratiosuggested diminished capacity for complex carbohydrate degradation in captive individuals. The results of microbial functional prediction suggested that AD populations displayed heightened microbial genes linked to vitamin and amino acid metabolism, alongside decreased genes associated antibiotics biosynthesis (e.g., penicillin, cephalosporin, macrolides, and clavulanic acid) and secondary metabolite degradation (e.g., naphthalene and atrazine). These microbial alterations implied potential disparities in the health status between AD and wild individuals. AD populations exhibited varying degrees of microbial changes compared to the wild group, implying that the extent of these variations might serve as a metric for assessing the health status of AD populations. Furthermore, utilizing the individual information of captive individuals, we identified associations between variations in the gut microbiota of R. roxellana and host age, as well as pedigree. Older individuals exhibited higher microbial diversity, while a closer genetic relatedness reflected a more similar gut microbiota. CONCLUSIONS: Our aim was to assess how anthropogenic activities and host factors influence the gut microbiota of R. roxellana. Anthropogenic activities led to consistent changes in gut microbial diversity and function, while host age and genetic relatedness contributed to interindividual variations in the gut microbiota. These findings may contribute to the establishment of health assessment standards and the optimization of breeding conditions for captive R. roxellana populations.

Identification and expression analysis of lncRNA in seven organs of Rhinopithecus roxellana.

Long non-coding RNA (lncRNA) represents a new direction to identify expression profiles and regulatory mechanisms in various organisms. Here, we report the first dataset of lncRNAs of the golden snub-nosed monkey (GSM), including 12,557 putative lncRNAs identified from seven organs. Compared with mRNA, GSM lncRNA had fewer exons and isoforms, and longer length. LncRNA showed more obvious tissue-specific expression than mRNA. However, for the top ten most abundant genes in each organ, mRNAs expression was more tissue-specific than lncRNAs. By identification of specifically expressed lncRNAs and mRNAs in each organ, it indicates that the expression of SEG-lncRNA (specifically expressed lncRNA) and SEG-mRNA (specifically expressed mRNA) had high correlation. In particular, combined our lncRNA and mRNA data, we identified 92 heart SEG-lncRNAs targeted ten mRNA genes in the oxidative phosphorylation pathway and upregulated the expression of these target genes such as ND4, ATP6, and ATP8. These may contribute to GSM adaption to its high-elevation environment. We also identified 171 liver SEG-lncRNAs, which targeted 27 genes associated with the metabolism of xenobiotics and leaded to high expression of these target genes in liver. These lncRNAs may play important roles in GSM adaptation to a folivory diet.

Identification and expression profile of microRNA in seven tissues of the Golden snub-nosed monkey (Rhinopithecus roxellanae).

MicroRNAs (miRNAs) are key in the post-transcriptional regulation of gene expression and thus characterization of miRNAs and investigation of the relative abundance and specificity of tissue expression are essential for understanding gene expression in the golden snub-nosed monkey (GSM, Rhinopithecus roxellanae). Here, we report the first dataset of GSM miRNAs where we identified 460 miRNAs in seven tissues, with 246 conserved known mature miRNAs and 214 novel mature miRNAs. We determined miRNA abundance and expression in the seven tissues using a Tissue Specificity Index score and found that most novel GSM miRNAs showed a highly tissue-specific expression pattern. In particular, 67 novel miRNAs and the miR-34 family were expressed in abundance only in the lung. Five known miRNAs were highly abundant in digestive organs such as the pancreas and liver, and four novel miRNAs were highly expressed in the heart and muscle. Annotation of target genes of GSM miRNAs indicated that target genes were enriched in many important pathways, such as the HIF-1 signaling pathway and xenobiotic biodegradation-related pathways. Collectively, these results emphasize that miRNAs play important roles in GSM diet and high-elevation adaptation regulation. In summary, this study provides essential information on GSM miRNAs and will benefit further investigations of the function and mechanism of miRNAs in controlling gene expression in the GSM.

Genetic assessment of eight zoo populations of golden snub-nosed monkey (Rhinopithecus roxellana) implication to the conservation management of captive populations.

Captive breeding programs play an important role in preserving the genetic diversity of endangered species. It is of utmost importance to conduct genetic assessment for captive populations in order to develop scientific breeding plans and conservation management strategies. Here, we genotyped 10 microsatellite loci and sequenced 368 bp of mitochondrial DNA control region for the golden snub-nosed monkey (Rhinopithecus roxellana) from eight captive populations in China, and compared the genetic indices of captive populations with a wild population. Meanwhile, we performed paternity tests to verify the genealogical records and established genetic lineages. A total of 157 individuals were identified from 161 fecal samples, including 135 captive individuals (approximately 25% of captive individuals in China). Microsatellite analysis showed that the nine populations had moderate levels of genetic diversity, with polymorphism information content (PIC) ranging from 0.43 to 0.542; the genetic diversity of captive populations (average PIC: 0.503) was slightly higher than that of the wild population (PIC: 0.438). The Structure analysis indicated that individuals of the eight captive populations contained two different genetic components. We conducted either single-blind or double-blind paternity testing on 40 offspring of captive individuals and found that five offspring from two zoos (Nanjing Hongshan Forest Zoo and Shanghai Wild Animal Park) showed discrepant kinships from their pedigree records, probably due to the inaccuracies in pedigree records. By constructing genetic pedigrees, inbred offspring were found in Beijing Zoo, Shanghai Zoo, Hangzhou Zoo, and Chengdu Zoo. Analysis based on mitochondrial DNA showed a high level of genetic diversity in the eight captive populations (mean nucleotide diversity: 0.047). However, no nucleotide diversity was found in the wild population. This study conducted a genetic survey for captive golden snub-nosed monkeys and will significantly benefit the genetic conservation management for captive populations in the future.

Genome-wide screening of microsatellites in golden snub-nosed monkey (Rhinopithecus roxellana), for the development of a standardized genetic marker system.

Golden snub-nosed monkey (Rhinopithecus roxellana) is an endangered primate endemic to China. The lack of standardized genetic markers limits its conservation works. In the present study, a total of 1,400,552 perfect STRs was identified in the reference genome of R. roxellana. By comparing it with the 12 resequencing genomes of four geographical populations, a total of 1,927 loci were identified as perfect tetranucleotides and shared among populations. We randomly selected 74 loci to design primer pairs. By using a total of 64 samples from the Chengdu Zoo captive population and the Pingwu wild population, a set of 14 novel STR loci were identified with good polymorphism, strong stability, high repeatability, low genotyping error rate that were suitable for non-invasive samples. These were used to establish a standardized marker system for golden snub-nosed monkeys. The genetic diversity analysis showed the average HO, HE, and PIC was 0.477, 0.549, and 0.485, respectively, in the Chengdu Zoo population; and 0.516, 0.473, and 0.406, respectively, in Pingwu wild population. Moreover, an individual identification method was established, which could effectively distinguish individuals with seven markers. The paternity tests were conducted on seven offspring with known mothers from two populations, and their fathers were determined with high confidence. A genotyping database for the captive population in the Chengdu Zoo (n = 25) and wild population in Pingwu country (n = 8) was acquired by using this marker system.

Divergence of Fecal Microbiota and Their Associations With Host Phylogeny in Cervinae.

Gastrointestinal microbiota may shape the adaptation of their hosts to different habitats and lifestyles, thereby driving their evolutionary diversification. It remains unknown if gastrointestinal microbiota diverge in congruence with the phylogenetic relationships of their hosts. To evaluate the phylosymbiotic relationships, here we analyzed the compositions of fecal microbiota of seven Cervinae species raised in the Chengdu Zoo. All sampled animals were kept in the same environmental condition and fed identical fodder for years. Results showed that Firmicutes and Bacteroidetes were dominant in their fecal microbiota. Even though some bacteria (e.g., Ruminococcaceae) were found to be common in the feces of all investigated species, some genera (e.g., Sharpea and Succinivibrio) were only observed in animals with particular digestive systems. As for the intraspecies variations of microbial communities, only a few operational taxonomic units (OTUs) were shared among replicates of the same host species although they accounted for most of the total abundance. Correlation was observed between the fecal microbiota divergence and host phylogeny, but they were not congruent completely. This may shed new light on the coevolution of host species and their microbiota.

[Study of effects of copper deficiency on internal organ through a copper deficiency model in rat].

OBJECTIVE: To establish copper deficiency model in rats, and observe the damnification on internal organ of copper deficiency rats. METHODS: 27 male weanling SD rats with 5-week-old were randomized into 3 groups (n = 9), i.e., control group 1, control group2 and copper deficiency group (CuD). The rats of the control group 1 were fed commercial feed with copper level of 7.0 mg/kg, the rats of the control group 2 and the copper deficiency group were fed half-purified diet with copper level of 0.73 mg/kg. In afternoons, rats were orally perfused copper sulphate solution with copper concentration 0 (control group 1), 0.133 (control group 2) and 0 mg/ml (copper deficiency group), respectively, the volume was 1% of body weight, so theory copper level of the feed in the control group2 was 11.37 mg/kg. All of rats had free access to both food and de-ionized water. Rats were sacrificed at the end of test feeding on the 42nd day, blood was sampled for analyzing the plasma ceruloplasmin activity (PCP) and its content (PPD), and erythrocyte Cu-Zn SOD (EC Cu-Zn SOD); liver was sampled for analyzing the content of Metallothionein (MT), and liver copper (LC). The organic tissues of kidney, brain, heart, liver, spleen, lung and testes are sampled for histopathologic examination. RESULTS: The PCP and EC Cu-Zn SOD, PPD, LC and LMT of rats in copper deficiency group was significantly lower than those of rats in control group1 and control group2 (except EC Cu-Zn SOD) (P < 0.01). The cardiac muscle fibers of a part of rats in copper deficiency group were broken and eosinophilic. The endothelial cell of a coronary artery branch was presented proliferation and swelling, subendothelial space was broadened. An arteriole in the lung was showed thickening of the wall, and presented obliteration of the lumen. No obvious pathological changes of other internal organ were found. CONCLUSION: Copper deficiency model in rats is successfully established after rats ingesting diet of low copper for 42 days. Slightly pathologic changes in the cardiovascular tissues of part of rats in copper deficiency groups are observed.