Integrated transcriptomic and metabolomic analysis of the hypothalamic-pituitary-testicular axis in rooster lines...

This study aimed to clarify the molecular regulatory mechanisms of the hypothalamic-pituitary-testicular (HPT) axis in rooster lines with distinct hatchability. Two groups of roosters characterized by either high (H) or low (L) hatchability were evaluated. Semen quality and antioxidant capacity were measured, followed by transcriptome, metabolome, and O2PLS integration of the three tissues comprising the HPT axis. Results showed semen quality did not differ significantly between the two groups (P > 0.05), while seminal antioxidant capacity was significantly greater in the H group (P < 0.05). Differentially expressed genes were mainly enriched in transcriptional regulation, signal transduction, and steroid hormone metabolism pathways, whereas differentially expressed metabolites were concentrated in amino acid and lipid metabolism. Integrated analysis detected four potential genes (TGM4, SYCP1, CSPG5, and GABRA5) and two potential metabolites (N-Acetyl-arginine and prostaglandin D2). These findings suggest that the transcriptional and metabolic profiles within the male HPT axis, alongside seminal antioxidant status, appear to relate to offspring hatchability. Our work provides new insights into the molecular basis of hatching differences between rooster lines.