The Effect of Insulin Like Growth Factor-1 (IGF-1) Supplementation in Maturation Media on Transforming Growth Factor-Beta (TGF-β) and Growth Differentiation Factor-9 (GDF-9) Expression in Kacang Goat Oocytes

| Kacang goats, native to Indonesia, play a vital role in enhancing food security and supporting rural economies. Nonetheless, their population and genetic quality are still not at an optimal level. In vitro maturation (IVM) plays a crucial role in genetic conservation, by impacting oocyte competence and embryonic development. This research assessed the impact of insulin-like growth factor-1 (IGF-1) supplementation in the maturation medium on the expression of TGF-β and GDF-9 in Kacang goat oocytes. Oocytes were harvested from goat ovaries and subjected to in vitro maturation with IGF-1 at concentrations of 0 (control), 50, 100, and 150 ng/mL. Immunocytochemistry evaluated the expression of TGF-β and GDF-9. Oocytes exposed to 100 ng/mL IGF-1 exhibited a marked increase in the expression of TGF-β and GDF-9 compared to other groups (p < 0.05). A significant positive correlation exists between TGF-β and GDF-9 (r = 0.499; τ = 0.424; p < 0.05). The results indicate that 100 ng/mL IGF-1 effectively promotes oocyte maturation through the activation of signaling pathways. In summary, administering 100 ng/mL IGF-1 is advised to enhance oocyte quality in Kacang goats, which may lead to improved IVF outcomes.