Transcriptional changes in Tibetan pig ovaries and spleen during gestation

The Tibetan pig, as a typical highland breed, has a higher newborn-to-sow weight ratio than low-altitude breeds, which may be associated with better offspring survival in high-altitude environments. This suggests Tibetan pigs need a healthier physiological state during gestation. Understanding physiological changes during pregnancy is thus crucial for improving their reproductive performance. The ovaries secrete pregnancy-related hormones, while the spleen regulates immunity as a key immune organ. Both are vital for maintaining maternal health, yet their physiological changes during pregnancy in Tibetan pigs remain unclear. This study compared the transcriptome changes of the ovaries and spleens in non-pregnant and pregnant Tibetan pigs. The ovaries showed more pronounced transcriptional changes, with 757 differentially expressed PCGs (466 upregulated, e.g., ISM1, PRKAA2, STAR, CEBPB; 291 downregulated, e.g., BMP15, MOS) and 53 differentially expressed lncRNAs (34 upregulated, 19 downregulated). In the spleen, 229 PCGs were differentially expressed (76 upregulated, e.g., ISM1, PRKAA2, ESR1, CXCL8; 153 downregulated, e.g., NFATC4), along with 14 differentially expressed lncRNAs (5 upregulated, 9 downregulated). Functional analysis revealed enhanced ovarian hormone synthesis and suppressed oocyte activity, alongside reduced splenic inflammation during pregnancy. Notably, both organs showed increased lipid metabolism, and inflammation-related pathways were activated in the ovaries. Key candidate genes and regulatory factors potentially involved in pregnancy-related changes were also predicted. Overall, this study highlights transcriptional shifts in Tibetan pig ovaries and spleens during pregnancy, offering insights into plateau animal reproduction and strategies to improve Tibetan pig fertility.