Crossbreeding between Duroc and Pietrain breeds is widely applied in genetic improvement programs to enhance productivity and carcass quality, aligning with sustainability goals and consumer demands. Additionally, sex is a relevant factor influencing performance and carcass traits. This study evaluate performance, carcass characteristics, and primary cut weights in pigs from different genetic lines and sexes, as well as their interactions. A total of 600 pigs were evaluated across three sire lines: Line d- Duroc, Line H- Hybrid (Duroc and Pietrain), and Line P- Pietrain, including both females and immunocastrated males (ICM). At the end of the growing period, 120 animals with body weights closest to the pen average were selected for slaughter and carcass analysis. No significant interactions were observed between genetic line and sex (P ≤ 0.05). ICM showed superior average daily gain (ADG), final weight, feed conversion (FCR), and backfat thickness, while females had higher carcass yield and lean meat percentage. D and H lines outperformed P in carcass yield and weight, whereas P had greater backfat thickness but lower lean percentage and loin depth. For primary cuts, ICMs had heavier bellies, while females yielded more lean cuts. The results underscore the impact of genetic and sex-based selection on pork quality and sustainability.

• The SO diet has an anti-inflammatory effect on the liver of pigs. • MUFA has a pro-inflammatory effect compared to PUFA n-6 or n-3. • The CO has a higher antioxidant effect than other diets.

Lipids are important for metabolic processes, mainly cytokine regulation in the skeletal muscle and liver. Considering the soybean oil concentration, a weighted gene co‐expression network analysis (WGCNA) was used to perform an integrative analysis in skeletal muscle and liver tissues. Using this approach, this research aimed to investigate the integrative response to soybean oil supplementation in two different tissues to discover molecular responses, especially inflammatory responses. For this integrative analysis, sample collection, RNA sequencing, and WGCNA were carried out on immunocastrated male Large White pigs supplemented with 1.5% or 3.0% soybean oil. Co‐expression of some genes was revealed, such as those related to lipid metabolism and phosphotransferase activities in the skeletal muscle, or oxidative stress and methylation in the liver. Thus, we demonstrated that soybean oil supplementation leads to responses in skeletal muscle and liver, revealing that this supplementation improves the metabolism and inflammatory responses of healthy pigs.

Nutrigenomics investigates how nutrients modulate gene expression. Among them, fatty acids (FA) play important roles in regulating gene transcription, while long non‐coding RNAs (lncRNAs) may be associated with gene regulation and metabolic diseases. This study aimed to analyze the hepatic transcriptome of pigs, a species frequently used as a model for nutrigenomic studies, to identify novel lncRNAs and their potential target genes in response to diets containing different sources of FA. Seventy‐two pigs were fed four diets supplemented with 1.5% soybean oil (control), 3% canola oil, 3% fish oil, and 3% soybean oil. RNA sequencing of liver samples was performed to identify novel lncRNAs. Weighted Gene Co‐expression Network Analysis (WGCNA) was used to identify modules associated with phenotypic traits related to lipid metabolism and inflammation. Functional enrichment analyses were then conducted to annotate genes within these modules using Gene Ontology (GO) terms and to assess overlap with Quantitative Trait Loci (QTL). The results revealed 106 novel lncRNAs potentially regulating genes associated with lipid metabolism and immune responses in pigs fed diets with different FA sources. These findings enhance understanding of the regulatory role of lncRNAs in pigs and reinforce their relevance as models for human metabolic diseases.

Pork is a major source of animal protein worldwide, and its quality is influenced by pre- and post-slaughter procedures. Advances in molecular biology, particularly gene expression studies, support genetic improvement programs by enabling precise strategies to enhance meat quality and economic sustainability. This study evaluated meat quality traits and candidate gene expression in muscle and subcutaneous adipose tissue from different genetic lineages and sexes. A total of 120 pigs from three lineages—Line D (½ Duroc × ½ DB90), Line P (½ Pietrain × ½ DB90), and Line H (½ [Duroc and Pietrain] × ½ DB90); including immunocastrated males (IM) and females, were randomly selected. Meat quality was assessed using physicochemical parameters, and gene expression analysis was performed in 36 pigs using RT-qPCR with B2M, TBP, and RPL4 as references, and COL1A1, PRKAR2A, CAST, ADIPOQ, and PPARGC1A as targets. Lineage influenced drip loss and intramuscular fat, while lineage–sex interaction affected tenderness and color (L* and b*), and sex influenced b*. In muscle, sex affected COL1A1 and PRKAR2A, and lineage influenced COL1A1 and CAST. In adipose tissue, only CAST was lineage-dependent.

Lipid metabolism in pigs is a relevant model for understanding human metabolic regulation due to physiological similarities between the species. Alternative splicing (AS) generates transcript variants that can modulate metabolic pathways in the brain, liver, and skeletal muscle. This study aimed to identify and characterize AS events to explore the dynamics of AS under supplementation of soybean oil in these three tissues. We performed RNA sequencing in 36 pigs fed a soybean–corn diet supplemented with 1.5% or 3.0% soybean oil, using brain, liver, and muscle tissues. Expression matrices and structural annotation were generated for SUPPA analyses. Seven classes of splicing events were identified for each tissue, and only candidate genes exhibiting the highest differential proportion of spliced-in (DPSI) values were considered. Events were detected in both coding regions and 5’ UTRs, indicating potential functional consequences. Differential splicing was present in FRMPD1 for brain, G6PC3 for liver, and MED1 and FBXL20 for muscle. These findings suggest that AS may regulate lipid metabolism and that coordinated splicing responses across tissues could also influence the metabolic adaptation and growth performance.