Gut microbiome is associated with stereotypic behavior of the giant panda (Ailuropoda melanoleuca).

The giant panda (Ailuropoda melanoleuca) is a relict species endemic to China. Captive breeding has boosted its population. However, some captive individuals exhibit stereotypic behavior. Though extensive research showing that host behavior can be influenced by gut microbiota via the gut-brain axis, the gut microbiota related to stereotypic behavior of giant pandas has not been reported. To explore gut microbial composition and functional characteristics of stereotypically behaving (SB) giant pandas, the behavior of 15 captive giant pandas was observed, and their feces were analyzed using 16S ribosomal RNA (rRNA) sequencing (n = 145) and metagenomic sequencing (n = 45). Our study revealed distinct gut microbial diversity, composition, and functions between SB giant pandas and normal controls, indicating gut microbial dysbiosis in SB giant pandas. Serratia sp. Se-RSBMAAmG was significantly enriched in SB giant pandas, five Clostridium species and Lactococcus garvieae exhibited upward trends in SB individuals, whereas the probiotic Enterococcus hirae showed the opposite trend compared with those in normal controls. The Clostridium bacteria may affect propionate metabolism and the gamma-aminobutyric acidergic (GABAergic) synapse pathway, potentially affecting the emergence of stereotypic behavior. These findings suggest a link between gut microbiota and stereotypic behavior of giant pandas, providing novel insights for their conservation.