Study on the mechanism of induced ovulation in rabbits

Rabbits are induced ovulators, meaning they ovulate in response to mating or other physical and chemical stimuli. However, to date, research on candidate genes associated with ovulation in female rabbits remains limited, and the specific molecular mechanisms underlying ovulation in does are still unclear. Thirty healthy Hycole female rabbits were assigned to five groups: Group A (slaughtered immediately post-estrus as a baseline control), Group B (blank control), Group C (vaginal saline infusion), Group D (artificial insemination), and Group E (natural mating). Rabbits in Groups B through E were slaughtered 10 h post-treatment. Ovulatory follicles were observed exclusively in Groups D and E. Serum hormone analysis revealed significantly elevated levels of progesterone and luteinizing hormone in Group E compared to the other groups. Transcriptome analysis revealed that, compared to Group A, the ovarian tissue from Group C exhibited 686 differentially expressed genes (DEGs), while Groups D and E exhibited 645 and 637 DEGs, respectively. Functional enrichment analysis and protein-protein interaction (PPI) network construction identified several candidate genes, including RBP4, INHA, AKR1B10, S100A9, AKR1B1, INHBA, CYP19A1, and BMP2. These genes were primarily enriched in cytokine-cytokine receptor interaction, Hippo signaling pathway, and Pentose and glucuronate interconversions. These genes and their associated pathways collectively contribute to ovulation in rabbits, providing novel experimental data to further elucidate the mechanisms of stimulated ovulation. This research contributes to enhancing reproductive efficiency and advancing molecular breeding studies in rabbits.