Semen quality diagnosis by molecular approaches – SeQuaMol

Determination of bull semen methylome in association with the identification of histone modification pattern and protamin/histone ratio

- Methylation levels at the GNAS locus is not associated with field fertility in Holstein bulls.
-Epigenetics of bovine semen: tools for DNA methylation analysis

Work in progress according to the work plan of Se QuaMol

Communiqués de presse
- Newsletter de l'INRA «La lettre pour les entreprises«
(http://www.inra.fr/Entreprises-Monde-agricole)
www.inra.fr/Entreprises-Monde-agricole/Dispositifs-de-partenariat/Toutes-les-actualites/SeQuaMol

Posters
- Methylation levels at the GNAS locus is not associated with field fertility in Holstein bulls. Sellem E, Perrier JP, Kiefer H, Prezelin A, Acloque H, Congras A, Fritz S, Boichard D, Schibler L & Jammes H. European Cooperation in Science and Technology (COST) Action : EpiConcept Workshhop, Dubrovnik
(http://cost-epiconcept.eu/Epiconcept%20Proceedings%20Workshop%202015.pdf)
- Epigenetics of bovine semen: tools for DNA methylation analysis. Perrier J.P., Prezelin A., Jouneau L.,Piumi F., Sellem E., Fritz S., Boichard D., Weber M. , Schibler L., Jammes H. and Kiefer H. European Cooperation in Science and Technology (COST) Action : EpiConcept Workshhop, Dubrovnik
(http://cost-epiconcept.eu/Epiconcept%20Proceedings%20Workshop%202015.pdf)

Oral Presentations:
- Association of GNAS locus methylation status with field fertility in bulls. Sellem E. 12th International Symposium on Spermatology Association for Applied Animal Andrologists, 2014 New Castle Australie
- Epigenetics of bovine semen: tools to analyse DNA methylation. Perrier J-P, Prezelin A, Jouneau L, Sellem E, Fritz S, Renard J-P, Boichard D, Schibler L , Jammes H and Kiefer H. Session “New sources of phenotypes in cattle production”, 66th annual meeting of European Federation of Animal Science, Varsovie
- Combinations of in vitro assessed semen quality criteria to predict fertility of bull semen E. Sellem,
26th Annual European AI-Vets Meeting, Bulgarie
(http://www.esdar.org/esdar-conference-2015/ai-2015.html)
No patent

Sustainable breeding supposes to produce robust and resilient animals in order to cope with the diversity of environments as well as global changes and ensure good production levels and quality for present and future generations. Reproductive efficiency is a key factor for global efficiency and sustainability of both dairy and beef cattle industry. In a context of increased demand for animal products, improving reproductive efficiency may act on at least two pillars of sustainability: Economy, by increasing competitiveness, and Environment, by limiting resources and energy waste as well as environmental footprint of cattle breeding.
Semen used for artificial insemination (AI) is the main vector of genetic progress diffusion in bovine livestock (7 million of inseminated females in France and more than exported 2 million of AI straws)
Identifying sub-fertile bulls would improve animal breeding sustainability directly by reducing production loss (calves and milk), limiting extend of calving season and decreasing heifer culling rate (culled due to non-pregnancy). Sustainability would also be indirectly increased by limiting environmental impacts (reduced greenhouse gas emissions per kg of product, fewer consumed resources). Furthermore, infertile bulls can have adverse effects of animal welfare, due to repeated breeding and delayed calving. Thus, semen quality and bulls fertility represent a major issue that has for long stimulated researches on sperm characteristics associated with poor or successful fertilization events. Much progress has been made in this area, but they fail to efficiently address the question of embryonic development failure and pregnancy loss.
Labcom "Quality of the semen and cattle fertility: development of new molecular tools for diagnosis" will join forces from UMR INRA-ENVA 1198 and UNCEIA. It aims to precisely characterize semen at the molecular level, in order to evaluate the variability of these parameters according to multiple genetic, biological and environmental factors. An integrative approach will be implemented using the latest “omics" tools to acquire basic knowledge on semen composition as well as to establish the spermatic epigenetic landscape. These data will be used to evaluate their variability, in line with breed diversity, fertility and early embryo development. This work will allow the identification of new mechanisms or key genes essential for bull fertility and embryo development. Basic data on the impact of paternal inheritance on embryonic development and posterity will also been provided.
New and dedicated methods and technological tools will be developed by the Labcom, making it possible to validate both some biological hypotheses and the feasibility of the approaches. Based on its expertise, UNCEIA will optimize these tools and will contribute to their dissemination in its network and more widely at the international level. To perpetuate the Labcom, further research will be focused on biological processes impacted by some biomarkers, including small non coding RNAs and epigenetic alteration, on post implantation embryo development.