Progress in Research on Key Factors Regulating Lactation Initiation in the Mammary Glands of Dairy Cows

Abstract

Lactation initiation refers to a functional change in the mammary organ from a non-lactating state to a lactating state, and a series of cytological changes in the mammary epithelium from a non-secreting state to a secreting state. Like the development of the mammary gland, it is regulated by many factors (including hormones, cytokines, signaling molecules, and proteases). In most non-pregnant animals, a certain degree of lactation also occurs after exposure to specific stimuli, promoting the development of their mammary glands. These specific stimuli can be divided into two categories: before and after parturition. The former inhibits lactation and decreases activity, and the latter promotes lactation and increases activity. Here we present a review of recent progress in research on the key factors of lactation initiation to provide a powerful rationale for the study of the lactation initiation process and mammary gland development.

Progress of Conjugated Linoleic Acid on Milk Fat Metabolism in Ruminants and Humans

“…Furthermore, it is believed that increased milk fat synthesis in lactating cows and goats is linked to a high expression of SREBP1. This is because SREBP1 binds to sterol response elements in the promoter region of these genes, which regulates and activates the transcription of target genes primarily involved in lipogenesis [63]. SREBP1's beneficial influence on the mTOR signaling pathway contributes to the decreases in triglyceride production and mRNA expression of ACC, FAS, SCD, and FABP3 observed in dairy cow mammary epithelial cells transfected with SREBP1 siRNA [64].…”