Project description:Regulation of milk synthesis and secretion is controlled mostly through local (intra-mammary) mechanisms. To gain insight into the molecular pathways comprising this response, an analysis of mammary gene expression was conducted in 12 lactating cows shifted from twice daily to once daily milking. Tissues were sampled by biopsy from adjacent mammary quarters of these animals during the two milking frequencies, allowing changes in gene expression to be assessed within each animal. Using bovine-specific, oligonucleotide arrays representing 21,495 unique transcripts, a range of differentially expressed genes were found as a result of less frequent milk removal.
Project description:Transcript profiling was performed by Affymetrix microarray analysis and SAGE to characterize changes in gene expression in the bovine mammary gland in response to 4× versus 2× daily milking during the first week of lactation. These changes in gene expression may contribute to the increased milk production observed in response to increased milking frequency. Our results indicate that increased milking frequency alters expression of genes in the mammary gland related to increased extracellular matrix remodeling, neovascularization, metabolism, cell proliferation and apoptosis. Keywords: Physiological response to stimulus
