Análisis proteómico comparativo de proteínas del suero de baja abundancia en calostro de cerda y cabra

This study compared the whey proteome of sow colostrum (SC) and goat colostrum (GC) using shotgun proteomics combined with protein equalization techniques (CPLL or ProteoMiner™) to enhance the detection of low-abundance proteins. Colostrum samples were pooled from 11 hand-milked sows (20 mL each, collected at 0 h postpartum), while GC samples (2 liters total) were collected from 50 goats during morning milking on day 1 postpartum. A total of 86 low-abundance proteins (<30 kDa) were identified: 26 unique to SC, 32 to GC, and 14 shared. Major whey proteins, including α-S1, α-S2, β-casein, κ-casein, and lactotransferrin (LTF), were present in both colostra. Gene Ontology (GO) enrichment showed that SC proteins were mainly linked to biological regulation (49.04%) and immune response (11.49%), whereas GC proteins were associated with metabolic processes (26.98%) and biological regulation (26.43%), likely reflecting species-specific physiological differences. Protein–protein interaction (PPI) analysis identified highly connected proteins such as LTF, α-lactalbumin, β-casein, Apolipoprotein, and Clusterin in both networks, with additional interactions involving serum albumin in SC. GC displayed unique interactions with Glycam-1, a glycosylated adhesion molecule related to the milk mucin complex, though its immune role remains unclear. These findings provide novel insight into the functional whey proteome of SC and GC, particularly regarding low-abundance proteins, and highlight the value of shotgun proteomics with protein equalization. Surplus goat colostrum emerges as a sustainable heterologous source to enhance piglet survival in hyperprolific systems. The study also underscores the need for parallel gel replicates to minimize technical variability in future proteomic analyses.