Know more

About cookies

What is a "cookie"?

A "cookie" is a piece of information, usually small and identified by a name, which may be sent to your browser by a website you are visiting. Your web browser will store it for a period of time, and send it back to the web server each time you log on again.

Different types of cookies are placed on the sites:

  • Cookies strictly necessary for the proper functioning of the site
  • Cookies deposited by third party sites to improve the interactivity of the site, to collect statistics

Learn more about cookies and how they work

The different types of cookies used on this site

Cookies strictly necessary for the site to function

These cookies allow the main services of the site to function optimally. You can technically block them using your browser settings but your experience on the site may be degraded.

Furthermore, you have the possibility of opposing the use of audience measurement tracers strictly necessary for the functioning and current administration of the website in the cookie management window accessible via the link located in the footer of the site.

Technical cookies

Name of the cookie

Purpose

Shelf life

CAS and PHP session cookies

Login credentials, session security

Session

Tarteaucitron

Saving your cookie consent choices

12 months

Audience measurement cookies (AT Internet)

Name of the cookie

Purpose

Shelf life

atid

Trace the visitor's route in order to establish visit statistics.

13 months

atuserid

Store the anonymous ID of the visitor who starts the first time he visits the site

13 months

atidvisitor

Identify the numbers (unique identifiers of a site) seen by the visitor and store the visitor's identifiers.

13 months

About the AT Internet audience measurement tool :

AT Internet's audience measurement tool Analytics is deployed on this site in order to obtain information on visitors' navigation and to improve its use.

The French data protection authority (CNIL) has granted an exemption to AT Internet's Web Analytics cookie. This tool is thus exempt from the collection of the Internet user's consent with regard to the deposit of analytics cookies. However, you can refuse the deposit of these cookies via the cookie management panel.

Good to know:

  • The data collected are not cross-checked with other processing operations
  • The deposited cookie is only used to produce anonymous statistics
  • The cookie does not allow the user's navigation on other sites to be tracked.

Third party cookies to improve the interactivity of the site

This site relies on certain services provided by third parties which allow :

  • to offer interactive content;
  • improve usability and facilitate the sharing of content on social networks;
  • view videos and animated presentations directly on our website;
  • protect form entries from robots;
  • monitor the performance of the site.

These third parties will collect and use your browsing data for their own purposes.

How to accept or reject cookies

When you start browsing an eZpublish site, the appearance of the "cookies" banner allows you to accept or refuse all the cookies we use. This banner will be displayed as long as you have not made a choice, even if you are browsing on another page of the site.

You can change your choices at any time by clicking on the "Cookie Management" link.

You can manage these cookies in your browser. Here are the procedures to follow: Firefox; Chrome; Explorer; Safari; Opera

For more information about the cookies we use, you can contact INRAE's Data Protection Officer by email at cil-dpo@inrae.fr or by post at :

INRAE

24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

Menu Logo Principal Institut Agro Rennes-Angers

Home page

Plasticity of the mammary gland: lineage and characterization of the mammary epithelial cells in dairy cows

Thesis: Plasticity of the mammary gland
Characterizing the mammary cell populations, from the adult stem cells to the secretory epithelial cells: a new approach to improve the mammogenesis and to predict the efficiency of milk production of the dairy cows.

Since 2015, the dairy sector has to reorganize to go on producing in absence of quotas and new challenges appear. Indeed, the world demand for milk and dairy products increases year by year, in particular in China. In addition, this sector has to compose with the societal expectations on the environmental impact related to the cattle farm (breeding). In this context, Research on the lactation of the dairy cow and in particular on the mammary gland function seems as an important lever in the understanding on the animal adaptation to these new practices of breeding.

Understand the plasticity of the mammary gland from the cells which compose it

Milk in dairy cows is produced by the mammary gland, a complex and dynamic organ composed of several cellular types integrated into an extracellular matrix micro-environment. The milk is secreted by the epithelial cells within the alveoli of the mammary gland. In the epithelial populations, we distinguish the luminal cells which synthesize the constituents of milk, of the basal cells located at the galactophores ducts and the myoepithelial cells in border of acini responsible for the ejection of secreted milk. Epithelial cells are lined by others populations: the fibroblasts which connect cells within the tissue by producing the extracellular matrix, the adipocytes storing energy and the endothelial cells lining the blood vessels which provide nutrients to mammary gland. All together, these populations participate in production of milk.

Glande mammaire bovine - histologie

 

The proliferative and regenerative capacities of the mammary tissue during the reproductive cycles and lactation make of the mammary gland a unique organ enable to renew 50% of its cells during one lactation (Capuco et al., 2001). Stem cells are found in the mammary epithelium, these cells able to self-renewal largely contribute to the plasticity of the gland during the reproductive cycles (pregnancy, lactation, and involution). It was established that the epithelial stem cells were able to differentiate in progenitor cells, committed in a differentiation pathway but retaining substantial proliferation capacity, and that these cells gave rise to differentiated epithelial cells responsible for milk synthesis (Capuco et al., 2012).
The role of adult mammary stem cells and progenitor cells has been studied extensively in murine and human models. However, the fate and plasticity of these cells during a lactation cycle are not yet characterized in dairy cows. Thus, the lineage and the functional characterization of mammary epithelial populations, from the stem cells to differentiated cells would establish precisely the phenotype of the mammary gland in accordance with a particular physiological stage.

The objectives of this thesis

  • identify specific surface markers of the different cell types present in the mammary gland
  • isolate and characterize in vitro these different cell types from mammary explants
  • study their potential for differentiation / dedifferentiation / transdifferentiation in vitro

The purpose of this project is to identify markers of mammary stem cells to predict and detect the future dairy potential. This project will thus provide data for our understanding of stem cell function in ruminants and will contribute to develop biomarkers to  improve  mammogenesis and milk production.

Laurence Finot, laboratory tecnician at Pegase has been working on this subject of thesis since September 2015 for 3 years. She is supervised by Frédéric Dessauge in the lactation team.

Bibliographie

  • Capuco AV, Wood DL, Baldwin R, McLeod K and Paape MJ 2001. Mammary cell number, proliferation, and apoptosis during bovine lactation: relation to milk production and effect of bST. Journal of Dairy Science 84, 2177-2187. (DOI)
  • Capuco AV, Choudhary RK, Daniels KM, Li RW and Evock-Clover CM 2012. Bovine mammary stem cells: cell biology meets production agriculture. Animal 6:3, 382-393. (DOI)

Contact

Laurence Finot, laurence.finot[at]rennes.inra.fr (doctorante)
Frédéric Dessauge, frederic.dessauge[at]rennes.inra.fr (encadrant)