# Metagenomic Comparison of Gut Microbes of Lemur catta in Captive and Semi-Free-Range Environments

## TL;DR

This study compares the gut microbes of ring-tailed lemurs in captivity versus semi-free-range settings, finding that captivity leads to less diverse microbes and more potential pathogens.

## Contribution

The study reveals how rearing conditions affect gut microbiome diversity and pathogen presence in ring-tailed lemurs.

## Key findings

- Captive lemurs have less microbial diversity and more potential pathogens compared to semi-free-ranging lemurs.
- Semi-free-ranging lemurs show higher levels of microbes involved in fiber degradation and short-chain fatty acid production.
- Captive lemurs have a more homogeneous gut microbiota with altered enzyme gene profiles for polysaccharide degradation.

## Abstract

This study employed metagenomic methods to assess the differences in the fecal microbiomes of captive and semi-free-ranging ring-tailed lemurs (Lemur catta). The results indicate that captivity alters the community structure of the fecal microbiota of Lemur catta. Differences in the living environment resulted in variations in microbial functions and in the profiles of carbohydrate-active enzyme genes. Furthermore, the microbial community composition among captive ring-tailed lemurs was more homogeneous, yet it harbored a higher abundance of potential pathogens, suggesting that a captive lifestyle may adversely affect gastrointestinal health.

In order to protect endangered species, many zoos adopt diverse rearing models to achieve optimal conservation outcomes. This study employed metagenomic approaches to assess differences in the fecal microbiome of captive and semi-free-ranging ring-tailed lemurs (Lemur catta). The results show that captivity significantly altered the microbial community structure. The inter-individual variability in the microbial community within the captive-bred (CB) group was lower than that in the semi-free-ranging (FR) group, yet these individuals harbored a higher abundance of potential pathogens (Treponema_D). In contrast, microbial genera associated with fiber degradation and short-chain fatty acid production in the FR group were significantly elevated (Faecalibacterium, Roseburia, and Megamonas) as compared to the CB group. Environmental variations between the two rearing systems led to distinct profiles in microbial functions and carbohydrate-active enzyme gene composition. Notably, the FR group of lemurs exhibited an increased abundance of enzyme genes associated with the degradation of complex polysaccharides (cellulose, hemicellulose, and pectin), suggesting that their diet, rich in natural plant fibers, enhances the capacity of their gut microbiota to extract essential energy and nutrients. Conversely, the CB group displayed a more homogeneous microbial community with a higher prevalence of potential pathogens, implying that a captive lifestyle may negatively impact gastrointestinal health. These findings offer valuable insights into the influence of rearing conditions on gut microbial ecology and its potential implications for the health management of ring-tailed lemurs.