Biotechnological Advancements in Ovine Bioactives: Mapping Protein Expression Trends and Immuno-Lipidomic Dynamics for Functional Food Applications

This study explores the biotechnological applications of the ovine secretome by mapping protein expression trends and lipidomic dynamics in Chios (n = 5) and Karagouniko (n = 10) ewes during early lactation (1, 3, 5, 9, and 15 days post-partum-DPP). Immunoglobulin-G (IgG) expression was monitored via ELISA, lactoferrin (Lf) profiles were quantified using densitometric Tricine-SDS-PAGE, and fatty acid (FA) patterns were resolved by gas chromatography. Two-way mixed-factor repeated-measures ANOVA and Principal Component Analysis (PCA) revealed a highly significant temporal transition (p < 0.0001) across all components. Total IgG expression dropped sharply from DPP 1 (62.0–83.5 mg/mL) to day 15 (12.8–21.4 mg/mL), displaying a significant breed-by-time interaction (p < 0.0001), while the resilient Karagouniko breed exhibited a more buffered clearance slope. Conversely, local Lf mucosal expression followed a parallel, breed-independent temporal decay trajectory (p = 0.5877). Concurrently, saturated FAs decreased while monounsaturated and polyunsaturated fractions rose (p < 0.01), optimizing health-related lipid indices over time, including Atherogenicity (IA), Thrombogenicity (IT), and Health-Promoting (HPI). Unsupervised PCA successfully isolated early colostrum profiles based on coordinated immunological and lipidomic vectors. These findings demonstrate that tracking early secretome trajectories serves as a valuable, non-invasive indicator for translational veterinary medicine, establishing these genotype-specific fractions as potential substrates for future evaluation in bioactive functional food matrices research.