Differences in liver microRNA profiling in pigs with low and high feed efficiency.

Area of Science:

• Animal Science
• Genomics
• Molecular Biology

Background:

• Feed cost is a major economic challenge in the pig industry.
• Improving feed efficiency (FE) directly enhances profitability in pig breeding.
• The liver plays a crucial role in nutrient distribution and energy conversion, influencing FE.

Purpose of the Study:

• To identify key microRNAs (miRNAs) in pig liver associated with high and low feed efficiency.
• To understand the role of miRNAs in regulating gene expression related to FE in pigs.

Main Methods:

• Analysis of miRNA profiling in liver tissues of High-FE and Low-FE pigs.
• Identification and quantification of annotated and novel miRNAs.
• Differential expression analysis of miRNAs between High-FE and Low-FE groups.
• Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis.
• Validation of differentially expressed miRNAs using quantitative reverse transcription-polymerase chain reaction (qRT-PCR).

Main Results:

• A significant number of annotated and novel miRNAs were identified in pig liver.
• 14 miRNAs were found to be differentially expressed between High-FE and Low-FE pigs (9 upregulated, 5 downregulated).
• Target genes of differentially expressed miRNAs were enriched in key metabolic and signaling pathways (e.g., insulin signaling, GnRH signaling, mTOR signaling).
• qRT-PCR confirmed the sequencing results for selected miRNAs.
• Liver-specific miRNAs were shown to act synergistically with mRNAs to influence FE.

Conclusions:

• Liver microRNAs play a significant role in regulating pig feed efficiency.
• Specific differentially expressed miRNAs and their associated metabolic pathways provide insights into mechanisms controlling FE.
• These findings suggest potential miRNA-based strategies for enhancing swine FE and economic benefits.