TMT-Based Proteomic Analysis of Mature Milk versus Late Lactation Milk in Dairy Goats

The nutritional value of goat milk varies depending on the lactation stage. This study employed Tandem Mass Tag (TMT) proteomics to explore differential protein profiles between mature milk and late-lactation milk in Guanzhong dairy goats. Using differential screening criteria (fold change > 1.2, P-value < 0.05), we identified 48 differentially expressed proteins, with 39 significantly upregulated and 9 significantly downregulated. Proteins in mature milk appear to play more substantial roles in immune functions and lactation-related processes. Conversely, late-lactation milk may demonstrate greater suitability for cheese production and related dairy processing applications. These findings provide valuable insights for breeding improved dairy goat varieties and developing nutrient-rich functional dairy products.