Effect of sex on the gut microbiota characteristics of passerine migratory birds.

The gut microbiota, considered the "invisible organ" in the host animal, has been extensively studied recently. However, knowledge about the gut microbiota characteristics of passerine migratory birds during migration is limited. This study investigated the gut microbiota characteristics of three dominant migratory bird species (namely orange-flanked bluetail , yellow-throated bunting , and black-faced bunting ) in the same niche during spring migration and whether they were bird sex-specific.