Assisted reproductive technologies in livestock: from the field to fundamental studies
Historically, in vitro fertilization has been implemented in the bovine to increase the number of calves obtained from valuable cows. Our group developed for more than 25 years techniques and culture media to improve the number and quality of embryos obtained by this technique. By the time, the bovine embryos obtained from eggs collected on cow ovaries coming from local abattoirs proved to be an excellent model to study egg quality, egg maturation and the first phases of embryo development in mammals from the 1-cell stage up to the blastocyst stage (comprising roughly 200 cells).
Indeed, the bovine embryo develops slowly by comparison with the mouse one, which allows easily differentiating each step or transition. Moreover, its kinetics of development is closer to the human embryo than the mouse one. Last but not least, the biological material can be obtained without killing laboratory animals. We thus started to use it as main model for fundamental studies aiming to understand the roles of some proteins in early mammalian embryo development.
Our recent research mainly focuses on the different behaviour of male and female embryos exposed to specific environments and stresses. Indeed, well before the formation of the testis or ovaries, gender differences can be observed that can lead to different adaptations to specific environmental conditions. As a result, the preferential loss of embryos of one sex can sometimes be observed. But those differences can also have a long term impact after birth by differentially affecting the growth and health of the offspring on a sex-dependent manner.
We are also involved in projects aiming to preserve local Belgian livestock breeds through the implementation of a regional cryobank, housed at UCL, or to improve the fertility of specific bovine breeds, namely through nutritional optimization.