Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free:

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site:, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Google Analytics

Targeted advertising cookies


The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at or by post at:

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

Dernière mise à jour : Mai 2018

Menu Logo Principal

Home page

Genetic engineering : How to improve growth

INRA Prod. Anim. 3 (3), 207-214.


INRA Unité de Différenciation Cellulaire, 78352 Jouy-en-Josas cedex

Recent development in molecular biology makes the isolation of virtually any gene possible. The isolated gene can be mutated, in vitro, to modify its genetic message or its regulatory elements. It can then be reintroduced into cells or into the whole organism (transgenesis) and a physiological function can thus potentially be modified. These possibilities have been and still are being applied to animal growth. Genes coding for GRF (Growth Releasing Factor), GH (Growth Hormone), and IGF1 (Insulin-like Growth Factor) have been introduced into embryos of various animal species. These transgenes were expressed and this led to an acceleration of growth and to an increase in animal size. This phenomenon was accompanied by significant changes in the metabolism of the animals. The fact that the expression of the transgenes used could not be modulated led to an over secretion of GH, which is responsible for various physiological disorders, rendering most of the transgenic animals expressing a GH transgene of low interest for production. Although transgenesis has become a routine experiment in a certain number of laboratories, it remains relatively difficult on a large scale using most domestic animals. Further studies on the mechanisms which control transgene expression and on methods leading to transgenesis must be conducted before genetic engineering can really contribute to an improvement in animal breeding.

Download documents