Invited review: Accelerating mammary gland involution after drying-off in dairy cattle
Zhao, X., Ponchon, B., Lanctôt, S., Lacasse, P. (2019). Invited review: Accelerating mammary gland involution after drying-off in dairy cattle. Journal of Dairy Science (JDS), [online] 102(8), 6701-6717. http://dx.doi.org/10.3168/jds.2019-16377
Plain language summary
Thanks to advances in genetics, nutrition, and management, modern dairy cows produce substantially more milk than cows did 80 yr ago. There is therefore a need to re-evaluate the optimal drying-off method in the context of today’s high-producing cows. This review paper first describes the physiological processes and contributing factors during the drying-off and dry periods, then presents the reasons for shortening the dry period to less than 60 d, and lastly summarizes potential methods for hastening the involution process in dairy cows.
Bovine mammary gland involution, as a part of the reproductive cycle in dairy cows, is a very important remodeling transformation of the mammary gland for the subsequent lactation. There is considerable incentive to accelerate mammary gland involution to improve udder health, shorten the dry period, and simplify the management process by reducing dietary changes. The complex process of mammary involution is characterized by morphological changes in the epithelial cells and mammary tissue, changes in the composition of mammary secretions, and changes in the integrity of tight junctions. Involution is facilitated by elements of the immune system and several types of proteases and is coordinated by various types of hormones. This review first describes the involution process and then argues for the need to accelerate it. Last, this review focuses on various intervention methods for accelerating involution. Our aim is to provide a comprehensive overview of bovine mammary gland involution as well as potential techniques and new opinions for dry cow management.