Abstract
MicroRNAs (miRNAs) are small, non-coding RNA molecules that play crucial roles in the regulation of gene expression. In poultry, miRNAs have emerged as significant regulators of various biological processes, such as growth, development, immune response, and disease resistance in humans, plants, and animals. Recent studies have identified numerous miRNAs in different poultry species (chickens, geese, turkeys, quails, and ducks) and have elucidated their roles in various economically important traits in these species. This review aims to provide a comprehensive overview of the progress made in understanding the functions and mechanisms of miRNAs in poultry as well as the challenges faced in this field. Firstly, an overview of progress in the identification and validation of miRNAs in each species is provided. Then, specific roles of miRNAs in different classes of phenotypic traits are presented. Finally, the challenges and impacts of key technologies and methods, including artificial intelligence, genome editing, and single-cell sequencing, are discussed. From state-of-the-art research on miRNA functions across different trait classes to up-to-date technology trends, this review provides a comprehensive picture of miRNAs in poultry, which might open up new research and application possibilities.