Micro RNA research in cattle, pig, sheep, and chicken

MicroRNAs (miRNAs) are small non-coding RNAs that play key roles in regulating gene expression. Polymorphisms in miRNA precursors, target genes or within components of silencing machinery contribute significantly to the phenotypic diversity in animals. Due to this role miRNAs became the subject of increased research interest in association with production traits in livestock. In this article we presented examples of associations between miRNA genes and phenotypes of four livestock species: cattle, pig, sheep, and chicken. Most miRNA research studies are focused on their functioning in muscle, adipose tissues, gonads, fetal development and immune system. MicroRNA functions also impact animal productivity and consequently economic success of farming. With understanding miRNA functions in various biological pathways it is possible to develop new strategies for improving the productivity of livestock.