# Metagenomic–Metabolomic Integration Reveals Gut Microbiota Dynamics and Metabolic Changes in Super-Geriatric Captive Giant Pandas

## TL;DR

This study explores how aging affects gut microbes and metabolism in very old captive giant pandas, revealing changes that could help improve their health and care.

## Contribution

The study is the first to integrate metagenomic and metabolomic data to characterize age-related changes in gut microbiota and metabolism in super-geriatric giant pandas.

## Key findings

- Super-geriatric pandas show reduced beneficial microbes and increased opportunistic pathogens.
- Metabolomic changes include elevated unsaturated fatty acids and altered bile acid metabolites.
- Aging is linked to shifts in microbial function from biosynthesis to energy utilization pathways.

## Abstract

Advanced age can influence digestive function, metabolism, and immune-related processes in animals. The giant panda is a globally recognized flagship species for conservation, and with continuous improvements in husbandry practices and living conditions, the lifespan of captive individuals has increased. However, information regarding age-associated changes in super-geriatric giant pandas remains limited. In this study, we combined metagenomic and metabolomic analyses to examine fecal samples from captive adult and super-geriatric giant pandas. Our results showed that super-geriatric individuals exhibited a reduction in beneficial microbial taxa and an increased representation of bacteria with reported opportunistic pathogenic potential, together with notable alterations in lipid metabolism. These findings indicate age-associated changes in gut microbial composition and metabolic profiles. This study provides a scientific basis for improving dietary management and health monitoring of super-geriatric giant pandas, contributing to the welfare of captive individuals and supporting conservation efforts for this endangered species.

Age-related changes throughout the lifespan are known to influence gut microbiota composition, microbial functional potential, and host-associated metabolic processes. Understanding these age-related variations is important for elucidating their potential physiological implications at different life stages. However, information regarding the gut microbiome and metabolomic characteristics of super-geriatric captive giant pandas (Ailuropoda melanoleuca) remains limited. In this study, fecal samples were collected from adult and super-geriatric captive giant pandas and analyzed using metagenomic sequencing combined with untargeted metabolomics. The gut microbiota of super-geriatric individuals exhibited a marked decrease in Bacillota and an enrichment of Pseudomonadota compared with adult individuals. Functional profiling revealed age-associated shifts in microbial metabolic potential, with a transition from biosynthesis-dominated pathways toward pathways related to substrate degradation and energy utilization. Metabolomic analyses further revealed pronounced metabolic alterations in super-geriatric giant pandas, including elevated levels of unsaturated fatty acids and changes in bile acid–related metabolites. Alterations in gut microbiota composition, particularly the relative enrichment of Pseudomonadota-associated taxa, were associated with inflammation-related metabolic features. Collectively, these findings indicate coordinated changes in gut microbial composition and metabolic profiles during aging. Overall, this study characterizes age-associated alterations in gut microbiota structure and fecal metabolic signatures in super-geriatric captive giant pandas, providing a scientific basis for future studies on microbiota–metabolism interactions and for improving nutritional management and health monitoring strategies in aged individuals of this endangered species.