Bovine mammary stem cells: new perspective for dairy science

Mammary stem cells provide for net growth, renewal and turnover of mammary epithelial cells, and are therefore potential targets for strategies to increase production efficiency. Appropriate regulation of mammary stem cells can potentially benefit milk yield, persistency, dry period management and tissue repair. Accordingly, we and others have attempted to characterize and alter the function of bovine mammary stem cells. However, research on mammary stem cells requires tissue biopsies which limit the quantity of samples available. Interestingly, different studies reported recently the identification of putative mammary stem cells in human breast milk and new data are available in ruminants for this issue. In this review we summarized the main achievements in this field for dairy cow science and describe the interesting perspectives open to manipulate milk persistency during lactation and to cope with oxidative stress during the transition period. The exciting possibility that stem cell expansion can influence milk production is currently under investigation. The identification of primitive cell types within cow’s milk may provide a non-invasive source of relevant mammary cells for a wide-range of applications.