Comparative Analysis of Gut Microbiota Among Captive Waterbird Species: Effects of Diet and Environmental Factors

The gut microbiota of avian species is influenced by a diverse array of factors, encompassing host genetics, environmental conditions, physiological states, dietary patterns and age, among others. With the advent of high-throughput sequencing technology, research into avian gut microbiota has gained momentum. The artificial lake within the zoo serves as a unique nexus between the natural and captive environments. Despite this, our understanding of the gut microbiota of waterbirds residing in such an artificial habitats remains limited. In this study, we focused on three distinct species of waterbird kept in the artificial lake and traditional enclosures. We used high-throughput sequencing technology to determine the faecal microbiome of 25 waterbirds from three species, including bar-headed goose (Anser indicus), ruddy shelduck (Tadorna ferruginea) and black-necked crane (Grus nigricollis). Our objective was to elucidate the composition and community structure of their gut microbiota, while exploring the nexus between dietary habits and gut microbiota. Our findings revealed that the dietary patterns and gut microbiota of ruddy shelducks and bar-headed geese exhibited similar traits. On the other hand, black-necked cranes, whose food primarily consists of fish and meat, possessed a gut microbiota optimized for the digestion of protein and fat. Notably, artificial lakes may support higher microbial diversity compared to cage feeding. The results underscore the significance of diet as the primary determinant of gut microbiota variation among the captive waterbird. This study provides implications for promoting the healthy growth and well-being of wild waterbird in captivity.