Pangolins are among the most critically endangered animals due to widespread poaching and worldwide trafficking.Captive breeding is considered to be one way to protect them and increase the sizes of their populations.However,comparative studies of captive and wild pangolins in the context of gut microbiota are rare.Here,the gut microbiome of captive and confiscated-rescued wild pangolins is compared,and the effects of different periods of captivity and captivity with and without antibiotic treatment are considered.We show that different diets and periods of captivity,as well as the application of antibiotic therapy,can alter gut community composition and abundance in pangolins.Compared to wild pangolins,captive pangolins have an increased capacity for chitin and cellulose/hemicellulose degradation,fatty acid meta-bolism,and short-chain fatty acid synthesis,but a reduced ability to metabolize exogenous substances.In addition to increasing the ability of the gut microbiota to metabolize nutrients in captivity,captive breeding imposes some risks for survival by resulting in a greater abundance of antibiotic resistance genes and virulence factors in captive pangolins than in wild pangolins.Our study is important for the development of guidelines for pangolin conservation,including health assessment,disease prevention,and rehabilitation of wild pangolin populations.