Temporal and spatial heterogeneity in milk and immune-related gene expression during mammary gland involution in dairy cows

This study demonstrates heterogeneity in tissue structure, and milk protein and immune-related gene expression in mammary glands of lactating dairy cows. This heterogeneity becomes more pronounced during involution which was induced by the termination of milking. In addition, the morphological and gene expression changes as well as increased mammary epithelial cell apoptosis occurs at different rates between cows. Understanding the mechanisms initiating these changes in lactating and involuting mammary provides an opportunity for enhancing milk production of the dairy cow.