<![CDATA[The Gembrong goat is an indigenous Indonesian germplasm currently in a critical status, highlighting the importance of effective reproductive management. This study aimed to characterize biomolecular changes in Gembrong goat blood plasma following PGF2α administration using FTIR spectroscopy and explore their potential relationship with reproductive physiology. This study involved six male Gembrong goats divided into two treatment groups: P1 (n=3), which received an injection of 75 μg PGF2α, and K0 (n=3), which received an injection of 1.5 ml physiological NaCl. Semen samples were collected 30 minutes after treatment, and blood samples were drawn from the jugular vein and processed to obtain plasma through centrifugation at 3500 rpm for 10 minutes. Plasma biomolecule analysis was conducted using Fourier Transform Infrared (FTIR) spectroscopy within a range of 4000–400 cm⁻¹ to identify biomolecular functional groups. Absorbance data from the FTIR spectra were then analyzed quantitatively using a t-test. The results showed that FTIR analysis identified major biomolecular constituents in blood plasma, including proteins, lipids, carbohydrates, nucleic acids, and calcium-associated compounds. Significant increases were observed in protein-related bands, particularly Amide A (p = 0.004) and O-H/N-H stretching regions (p = 0.005), as well as in specific DNA-associated (p = 0.023) and calcium phosphate-associated bands (p = 0.001 and p = 0.008) following PGF2α administration. In contrast, lipid- and carbohydrate-associated spectral regions showed no significant differences (p > 0.05) between treatment groups. PGF2α administration altered FTIR spectral characteristics of Gembrong goat plasma, particularly biomolecular regions associated with proteins, lipids, carbohydrates, and nucleic acids. These molecular changes provide preliminary evidence of physiological responses related to reproductive processes. Further studies integrating FTIR analysis with direct sperm quality assessment are required.]]>
