Integrated Analysis of mRNA and miRNA Expression Differ-ences and Regulatory Networks in Ovine Tail Fat Deposition

Fat stored in sheep tails helps them survive tough conditions by regulating body tem-perature and metabolism. Understanding how this fat develops is important for breeding leaner sheep, protecting different types of fat-tailed sheep, and studying hu-man metabolic diseases. We compared tail fat from two Chinese sheep breeds: Large-Tailed Han sheep (from Henan) and Small-Tailed Han sheep (from Shandong). The large-tailed sheep stored much more fat. By analyzing their genetic activity, we found key differences in molecules controlling fat production and storage. Important biological pathways related to sugar and fat processing were more active in the large-tailed sheep. We identified specific genes and regulatory molecules linked to tail fat growth, including several that may serve as markers for this trait. This study re-veals how sheep regulate tail fat development, providing knowledge to help farmers breed sheep with ideal meat quality through genetic selection. The findings may also aid research into human fat-related health problems.