# Comparative Analysis of Microbial Community Structure and Function in the Gut of South China Tigers Under Different Dietary Treatments

## TL;DR

This study compares the gut microbiota of South China tigers on different diets to understand how diet affects their health and conservation.

## Contribution

The study provides new insights into how dietary changes influence gut microbiota and antibiotic resistance in captive South China tigers.

## Key findings

- Feeding live prey was linked to upregulated genes related to antimicrobial resistance and bacterial infection.
- Frozen meat diets showed more efficient energy metabolism in gut microbiota.
- A total of 1251 antibiotic resistance genes were identified in the tigers' gut microbiome.

## Abstract

Compared with captive feeding, dietary changes in the wild environment can significantly alter the structure and function of tigers’ intestinal microbiota. This may have an impact on the health and adaptability of the host, as well as the success rate of reintroduction. Here, we performed shotgun metagenomic sequencing for a comprehensive analysis of the gut microbiota of South China tigers, assigning them to two dietary groups (LP group; FM group), thereby generating abundant, valuable data for this endangered subspecies. Therefore, we believe that this manuscript would provide scientific support for optimizing precision feeding schemes for South China tigers, reducing the risk of diseases and the transmission of drug-resistant bacteria, and also offer important references for improving the pre-reintroduction health assessment system and formulating conservation strategies for endangered felines.

The gut microbiota is a crucial component of a tiger’s health and plays a significant role in adapting to changes in food and the environment. Although extensive studies have been carried out on the gut microbiota of tigers, investigating the responses of gut microbial composition and function to preadaptation to wild predation patterns under captive conditions is particularly significant for South China tigers, given that it is the only tiger subspecies existing solely in captive settings at present. Here, we performed shotgun metagenomic sequencing for a comprehensive analysis of the gut microbiota of South China tigers assigned to two dietary groups (live prey group, LP group; frozen meat group, FM group), thereby generating abundant valuable data for this endangered subspecies. The results indicated that the core intestinal microbial composition was similar between the two dietary groups. Differential analysis revealed associations between dietary treatments and microbial abundance in the intestines of South China tigers. Functional gene analysis revealed that the LP group exhibited upregulation of genes and pathways related to antimicrobial resistance, bacterial infection-related disease, cell motility and proliferation, while the FM group displayed efficient energy metabolism. A total of 1251 antibiotic resistance genes (ARGs) were identified in the gut microbiome of South China tigers. The core resistome mainly included resistance to peptides, glycopeptides, tetracyclines, fluoroquinolones, and macrolides. In addition, the differences in ARGs between the LP group and FM group may be related to a broader range of animal tissues of live prey and the processing conditions of frozen meat. In summary, although feeding live prey did not change the core framework of the gut microbiota in South China tigers, it was associated with differences in microbial abundance, metabolic pathways, and antibiotic resistance gene profiles.